# Agent handoff — cross-machine continuity **Last updated: 2026-08-11.** `main` is **`b867f64`** — git integration Stage 1 **#227** (`*git-status*` / `*git-diff*`, no wire change), atop `ae84d58` **#234**, the LSP file-watcher correctness fix (issue #233 D1+D2, one review round; **D3 — the polling cost — is deliberately unfixed and is the ruled next lane**). Beneath them, in first-parent order: **#231** destination capture, **#232** worker identity Stage 1, **#228** discovery Stage 2, **#230** LSP LaTeX coverage, **#229** the gate `--protocol` build step, **#225** per-worktree gate target dirs, **#226** the R8 fixture fix, and **#224** the QoL docs retirement. **Only #227 and #234 are absorbed into §1 at this anchor**; the eight between carry their facts in their `docs/active-work.md` lanes, several of whose headers still say OPEN — trust this chain over any lane header, per the ledger's own rule. Previously **2026-08-08**: `main` was `9a26ac8` — GPU horizontal scroll **#223**, which **closes the QoL arc** (§1). Beneath it the arc's other four: **#222** TUI horizontal scroll, **#221** `ui.line-wrap` at protocol v22, **#220** GUI zoom, **#219** `full_grid` honored by the grid consumer. Beneath those, `db1bbe9` — the tree primitive **#217**, atop **#216**, which completed the macOS CI signal-integrity arc by retiring R2 and R4 with discriminating witnesses, atop **#215**, which built the registry. **That arc is retired**; its live residue (R1, R3, and the newer R5 and R6) is re-homed to the async-runtime, reap-ledger, and readiness-helper-audit lanes in `docs/active-work.md`. The live CI-triage rule in §5 points at `docs/ci-red-signatures.md`, which keys on **signature, not test name** — and, since 2026-08-06, on **signature plus date**: a red matching a retired row is a recurrence only if it *postdates* the retirement, and an earlier one corroborates instead. The hazards list this file used to carry is retired, and its two unevidenced entries are audit notes there. Previously **2026-08-04, as bottom-panel Stage 3 #213 — the adopter default flip, which COMPLETES ARC 7: omitting `display` now means the panel, and the workbench's panel half is done on both frontends. Beneath it the post-release accuracy pass #212 and Distribution Stage 1 #211 — released as v1.1.0, the first pmacs release with prebuilt binaries, which makes journey step 1 reachable without cloning the repository — and the CI CRDT coverage lane #209, the first time CI has ever compiled and run the `crdt` half of the test corpus, closing a gap that left 279 tests (including a REQUIRED `CLAUDE.md` gate) unexecuted for the project's whole life. Development moved to the laptop in the same session; the docs absorption #208 sits beneath it. Previously 2026-07-29, as bottom-panel Stage 2B-3 — the GPU panel band, compatible protocol-v21 activation, and the negotiated `panel_capable` flip, completing Arc 7 Stage 2 — opens atop `e003b81`. Beneath it, bottom-panel Stage 2B-2 (#187) — the daemon panel projection and the epoch machine — lands on `6c9e765`, which is the dired Stage 2 framing (#171) atop the resource-op delete guard framing (#186). Those two are framing-only: both are approved documents with no runtime code, and neither has begun implementation. Beneath them, the docs-only coherence listview correction (#189) and landed-state refresh (#185); the canonical landed base beneath those is `7586905`. The runtime anchor beneath them is the M4 config-sink race fix (#174) and bottom-panel Stage 2B-1 (#184). #174 is test-only. #184 is the substantive one — the reserved protocol-v21 bottom-panel wire family, dark by construction, with the production handshake deliberately still advertising v20 — following the Journey/GPU directory-target ratchet (#183), following Journey Stage 1a (#182), which made directory startup one coherent local/daemon/GPU path and incorporated the terminal configuration + copy mode landed-doc work (#180); following terminal copy mode (#178) — `C-c C-t` materializes a terminal's whole retained range into an ordinary buffer, plus `Buffer::set_generated_contents`, the first genuinely immutable generated-buffer write path — and its landed-doc pair (#168); following Lean 4 Stage 4a (#179) — the typed-edit consumer chain — and bottom-panel Stage 2A (#177), the classified census routing that makes every Projection-class consumer ask `primary_document_window`; the bottom-panel Stage 2 framing (#175), terminal configuration Stage 1 (#173) — profiles, scrollback, a per-terminal configurable escape key, and the `C-c t` opening binding — Lean 4 stages 3a and 3b (#167, #170), pmacs' first Lean language server; the GPU terminal input fix (#166), the double terminal-layout sync that made a GPU terminal untypable; the CRDT undo repro (#157), the inline-math landed-doc refresh (#172), the inline-math slice (#158), the first mathematical typesetting in pmacs; dired Stage 1 (#165), Lean 4 Stage 2 (#161), the dired framing pair (#163/#164), find-file (#162) — the dired arc's Stage 0 — COHERENCE.md (#163), Lean 4 Stage 1 (#160), the minimap blank-slab fix (#159), bottom-panel Stage 1 (#155), the inline-math re-scout (#154), the vterm PTY-flake fix (#153), and the GPU initial-target doc refresh (#152); and before that GPU initial-target (#148, protocol v20), following folding Stage 2 (#149) and its landed-doc refresh (#150), web grammars HTML+CSS (#146), the LaTeX Stage 1 / inline-math framing pair (#144/#145), folding Stage 1 (#142), one-command GPU invocation (#141), the documentation refresh (#140), Vterm Stage 3 (#135), tab-width rendering parity (#137), locals-query processing (#134), modeline detection (#132), mode system wiring (#129), config registry (#127), Vterm Stages 1–2 (#126/#130), and completed Themes Arc 4 (#120/#124/#125).** This file is the bridge between development machines. If you are an agent reading this on a fresh clone: this document plus the `docs/*-framing.md` files ARE your memory. Read this fully before taking on work, seed your persistent memory from it, and **update this file (and commit it) whenever project state changes materially** — the next machine reads it the way you just did. For volatile branches, checkpoints, verification, and recovery commands, read `docs/active-work.md` immediately after this file. ## 1. Where the project stands (2026-08-11) - **Git integration Stage 1 — MERGED as #227 (2026-08-11).** `*git-status*` (a `listview` panel over `git --no-optional-locks -C status --porcelain=v2 --branch -z`) and `*git-diff*` (file-level, plain generated text), plus an install-once `keys` extension on `listview`. No wire change; **Stage 2 (gutter markers) needs new `DecorationKind` variants — a `PROTOCOL_VERSION` bump — and must be scheduled alone.** Held unmerged behind issue #233 by user ruling, then landed the same day as #234, refreshed and re-gated on the merged base. Durable facts: - **Capture at invocation, never read at continuation — enforced by ONE mechanism, not four counters.** Review found FOUR instances of the same shape (ordering by `rev-parse` completion; `state.root` read mid-plan; no generation on the diff path; one byte inside a fix). `new_channel()` tickets answer "is this still the request in force?" — **two channels, deliberately**: status and diff are independent things a user asks for, so each gets its own ordering and what is shared is the mechanism. The async-continuation census (three continuations, one dispatcher, one synchronous impostor) lives in the PR and framing. - **macOS cannot hold a non-UTF-8 filename, and this project will hit it again.** APFS/HFS+ reject invalid UTF-8 at the syscall (`EILSEQ`, errno 92); Linux's VFS treats names as opaque bytes. It cannot be reached around the filesystem either: an index-only entry still fails `git status`'s lstat with `EILSEQ`, which git skips — **there is no macOS arrangement in which real `git status` names a non-UTF-8 path.** The fix pattern: split coverage along the line the platform draws — behaviour runs everywhere (rows supplied through the `_deliver_status` seam), only *provenance* is Linux-gated. A latent sibling in `gpu_invocation_acceptance`'s crdt module is recorded in the git lane. - **Both root-parsing bugs lived in a pattern.** `rev-parse --show-toplevel` gets exactly ONE trailing `\n` removed, by an explicit last-byte test: `\r` is a legal POSIX name byte, and `rev-parse` has **no `-z`** — it echoes a literal `-z` onto stdout with exit 0, checked against the installed git rather than assumed. `first_line` was deliberately left alone both times: its three callers feed the single-line status band, where truncation is right. - **`{:?}` on a string containing NUL cannot build a `-z` fixture** — Lua's decimal escape swallows following digits, so payloads are assembled as raw bytes with three-digit escapes, joined in Lua with `string.char(0)`. - **A copy renders `copied from`, but `kind` stays `"rename"` for both, deliberately.** Every behaviour keyed on it is identical; splitting would force every present and future consumer to spell both arms, and a forgotten arm silently degrades copies. The score byte carries the distinction where presentation needs it. - **LSP file watcher — D1+D2 MERGED as #234 (2026-08-11); D3 is next.** Issue #233: with any server that dynamically registers `workspace/didChangeWatchedFiles`, plain-string globs never matched (matched **relative** where LSP says **absolute** — rust-analyzer saw no file change, ever; gopls saw `go.mod` but never `.go`), and re-registering a live id leaked the previous pollers uncancellably (rust-analyzer registers twice under one id: 12 pollers, 6 unreachable). Invisible for three months until #232's activity indicator — §9's instrument doing exactly its job. Durable facts: - **The GlobPattern form travels with the pattern, and it is read FROM the pattern, not from the union arm.** `resolve_watcher` returns `(base, pattern, form)`; a leading `/` is what makes a string absolute. The first fix classified every string absolute — repairing rust-analyzer while silently breaking bare `*.txt`, a case that had worked since May. Review caught it (P1). - **A scan that completes after cancellation must not emit (P2).** The watcher coroutine spends most of a tick suspended in `read_dir` awaits with `_sleep` already cleared, so a cancel landing there had nothing to interrupt and the resumed scan emitted one stale batch under the superseded pattern. Cancellation and liveness are rechecked after the scan; `pmacs.lsp._after_scan_for_tests` (nil in production, handed the scan result) exists because no real timing produces that interleaving on demand — `git.lua`'s `_deliver_status` device again. - **F1's lesson fired twice in one lane.** The pre-existing test was insensitive (`**/` compiles to `.-`, which spans `/`, so it passes under either match subject) — and then the lane's own flat-pattern guard constrained the RelativePattern *object* arm while P1's regression lived in the *string* arm. A guard proves things about the arm it exercises, nothing more. - **All six watcher tests are mutation-verified, each bite failing only its own defect** — the two review fixes re-verified independently after review. - **D3 is deliberately unfixed and ruled next**: the walk still recurses into everything every 250 ms, six jobs per tick for rust-analyzer. The D3 lane in `docs/active-work.md` carries what was checked (no notify dependency, no ignore-list infrastructure) and the option space. - **QoL arc — CLOSED. All five stages merged (#219, #220, #221, #222, #223).** From one daily-driver report: terminal zoom broke TUI rendering and did nothing in the GUI, and a long line was unreadable past the edge. Both complaints are answered on both frontends. - **#219** made the grid TUI honor `full_grid`, so a post-resize resync blanks the host before repainting. - **`FG-INV` is a CONSUMER contract and lives on the protocol type.** A `full_grid: true` delta carries only the frame's **non-default** cells, so a consumer MUST blank its surface before applying them. The rule already existed — in the doc comment of a **private field on the producer's struct** — which is exactly why the one consumer never honored it. An invariant a consumer must satisfy belongs where consumer authors read it. - **Seven tests covered the flag and all seven tested the producer.** Every one asserted the producer *sets* it; none asserted a consumer *acts* on it, and no runtime reader existed anywhere in the workspace. "Add a test for the flag" had already been done. §5's *enforcement and documentation drift apart silently*, in a second register — and the reason a fix ships the contract and its consumer together. - **#220** gave the GUI native zoom over the font preference that already existed, quantizing the step so the round-trip guarantee is exact rather than approximately true. - **`install_state_dirs` is the eager-state-consumer seam.** Builtins and `init.lua` both run *before* it, so a `pmacs.state.read` at module load returns nothing, **always**. `saveplace` and `recentf` never meet this because **both read lazily**; zoom must apply with no user action, making it the **first eager state consumer**. Restore therefore lives at the end of `install_state_dirs` — by definition the moment state becomes readable, so a future third startup path cannot mis-order or miss it. **Any future eager consumer belongs at the same seam.** - **A GPU-only key binding cannot be expressed today.** `keymap_stack::Scope` is `Buffer | Mode | Global` with **no frontend identity**, and `FrontendEvent` has no command-invocation variant — so neither "bind on the GPU only" nor "the GPU asks for a command" exists. #220 shipped commands and no default bindings for that reason, not by preference. See the capability-aware keymap resolution backlog item in §6. - **#221** added **`ui.line-wrap`** — `ConfigKind::Enum` (`wrap`/`truncate`), default `wrap`, **buffer-local**, with `ui.toggle-line-wrap`. Both frontends honor it: the grid renderer through `Viewport`, the GPU through **`InstanceMessage::LineWrapFacts` at protocol v22**, resent on attach, config change, **and buffer switch** (the mode is per buffer, so a `FontFacts`-shaped global design is silently wrong). `ADVERTISED_PROTOCOL_VERSION` stays pinned at 20. Three durable consequences: - **GUI users lost word wrap.** The GPU document buffer's first explicit `set_wrap` is `Wrap::Glyph`. Character wrap is what the grid can implement identically without UAX #14; a whitespace approximation of cosmic-text's real breaking was judged worse than honest divergence. Word wrap is a clean additive third choice. - **`pmacs-protocol::scroll`** owns `ScrollPosition` and a pure `classify(first_visible, last_visible, byte_pos, byte_len)`. `pmacs-gpu` depends on `pmacs-protocol` and never on the `pmacs` lib, so the status readout had been duplicated *structurally* — and during this lane's own review a fix landed in one copy while the other kept reporting `All` for a wrapped one-line buffer. Each frontend supplies local layout facts and renders the string; the shared crate owns the decision. No wire message, no version bump. **Under `truncate` the old line-space formatter is untouched**, so its output is identical by construction. - **The GPU answers "is this byte on screen?" with `code_byte_painted`** — `code_byte_px` intersected with the drawable clip. Neither `view_range` (it carries `SCROLL_OVERSCAN` past the window) nor `scroll_top` (it ignores `code_scroll_residual`) can answer it. - **#222 made `truncate` navigable in the TUI**: moving the cursor past the right edge scrolls the view. **Automatic only** — no commands, no bindings (framing Q#HS2). Durable facts: - **`view_left` is an UNSNAPPED per-window display column, and each line derives its own effective edge.** A setter-time snap cannot exist: one column can bisect a wide glyph on one line and be an ordinary boundary on the next, so no single snapped value is canonical for every visible line, and snapping per line would break vertical alignment. Per-window (not buffer, unlike `ui.line-wrap`) because two panes on one buffer scroll independently. - **The walk stays LINE-absolute; only the emit translates.** Tab expansion depends on the absolute column from the line start, so a walk beginning at the edge puts tab stops in the wrong place. - **Every visible cell has a designated byte**: ordinary character → its own start; bisected wide glyph → the **glyph's start** (its trailing cell paints a styled blank, never a `Continuation`, which would name an off-screen cell); tab expansion → the byte **after** the tab (pre-existing, preserved). The wide glyph rounds backward and the tab forward, on one principle: every cell maps to the byte a user would mean by clicking it. - **`Viewport::visible_cols` is the single clip rule, with five adopters** — syntax/LSP styling, diagnostic underlines, search washes, `BufferStyleOverlay`, and the selection painter. Review found the first version had translated only the base glyph walk, leaving decorations painting at absolute columns; a second round found the selection painter keeping its own copy on a false premise about needing a different width. `StyleSpanOverlay`/`VirtualCellOverlay` are **excluded** by contract: viewport-relative already. - **`view_left` is reset to 0 on the wrap branch**, not merely ignored — inertness would leave a stale offset that reappears on the next toggle back to `truncate`. - **Persisted per leaf at `DESKTOP_VERSION = 1`** via `#[serde(default)]`. Nothing else in `src/desktop.rs` carries that attribute, so removing it makes serde reject every desktop saved before the field existed. A literal v1 JSON fixture guards it. - **No wire.** `view_left` is per-window viewport state, so no protocol message and no version bump. - **Stage 5 (#223) is the GPU half, and it closed the arc.** A split decided rather than inherited (framing Q#HS1). Framing in `docs/gpu-horizontal-scroll-framing.md`. The GPU is not a grid consumer, so it could not inherit `view_left`; it has its own `code_scroll_left`, in **pixels**, local viewport state with no wire and no version bump. - **The work was one transform and one clip, written before any consumer moved.** `code_x_to_screen` / `screen_x_to_code` (exact inverses) and `code_clip_left` / `crop_to_code_clip_left`. **glyphon honors `TextBounds`, so the text layers clip themselves; the manual quad and squiggle renderers do not** — and nothing needed them to before this stage, because no code-relative x could be negative. Five call sites deriving the offset independently is how the caret and its glyphs come to disagree. - **Washes crop, they do not drop.** A selection running in from off the left edge must paint the visible part — the same boundary Stage 4's review caught the TUI painter getting wrong. - **Two lifecycle resets, both observed pre-motion**: the wrap transition and the `BufferSnapshot`. A later cursor motion repairs the offset anyway, so a witness that waits for one cannot tell "reset on snapshot" from "repaired on first motion". - **`pmacs_protocol::scroll::follow_left`** — the follow rule now lives beside `classify` and **both frontends call it**; `src/editor.rs::horizontal_follow` delegates, and the GPU converts px ↔ columns around it (exact, because non-monospace code fonts are rejected). An approved exception to the stage's "local GPU viewport state" scope, recorded in the framing doc §1.2a. It moves no viewport state, adds no wire message, needs no version bump. - **Two witnesses exist because mutation testing found the TESTS wrong, not the code.** The gutter byte-identity test's "the code area must have moved" assertion is satisfied by a wash and the caret alone, so it **passed with `TextArea.left` pinned to the code origin** — the whole glyph-side mechanism was unwitnessed. And the completion predicate passed `line_height` as a *horizontal* extent, which the far-off-left test could not catch because 200px off-left fails a width-based predicate too. **Test a boundary AT the boundary**; the replacements straddle by ±0.05px. - **Beneath the QoL arc, at `db1bbe9`** (it was `main` until #219). The **tree primitive #217** — `listview` rows take optional `depth`/`id`, collapse is primitive-owned, folding is **local projection state and not a refresh protocol**, and the LSP outline is the sole adopter (`COHERENCE.md` §14 ◐; §20 says adoption, not construction). Atop `2657568` **#216**, which completed the macOS CI signal-integrity arc, atop `12f2970` **#215**, which built `docs/ci-red-signatures.md`. Beneath those, `f186253`: bottom-panel Stage 3 **#213** completes Arc 7, atop the post-release accuracy pass #212 and `000b6cd` / **v1.1.0**. Beneath that, Distribution Stage 1 #211 lands atop the docs absorption #210, the CI CRDT coverage lane #209, the absorption #208 and `cfc1710`. Beneath that, nine PRs landed in this order: the ledger absorption #199, the process-signal diagnostic #200, the test ambient-root isolation **framing** #201, the reap-ledger diagnostic #202, Journey Stage **1b-1** #203, **1b-2** #204 and **1b-3** #205, the ambient-root isolation **implementation** #206, and discovery Stage 1 #207. Each has its own bullet below; this line is the `db1bbe9` ancestry chain and nothing else. **The head-of-`main` anchor is at the top of this file** — it moved to `9a26ac8` at #223, and this bullet's own opening says so. - **Bottom panel Arc 7 COMPLETE — Stage 3 (#213), the adopter default flip.** Omitting `display` now means the panel for listview, compile and terminal; **dired keeps `"current"`** because `pmacs.path.directory_handler` calls it with no `display` and a flipped default would open `pmacs .` in a bottom panel. Four hand-written copies of the validator collapsed into one `resolve_adopter_display(operation, raw, default)` — the default is a **parameter**, which is what makes dired's exemption visible at its call site instead of hidden in a divergent copy. Durable facts: - **A visit FROM a panel must never use the raw switch.** `pmacs.window.switch_buffer` replaces the buffer in the ACTIVE window, so from a panel it clobbers the panel itself. The outline's `on_visit` still did this; the references panel had been migrated to `display_file` when the arc landed and the outline was missed, because nothing exercised it from a panel until the default flipped. **Q#BP11c is the contract**: after RET, `M-,` must FOCUS the still-present panel, not clone its buffer into the document — and an assertion on the active buffer name alone cannot tell those apart. - **An opt-out that does not survive replay is not an opt-out.** `compile._last` stored `{cmdline, cwd}` only, so `g` re-resolved `display` and silently reverted an explicit `"current"` to the new default. Anything that replays a stored invocation must store the escape hatch with it. - **Compile's chords are PANEL-LOCAL, deliberately.** All are bound `scope = "buffer"`, so with `select = false` none dispatch from the document — `C-c C-k` included. `M-x compile.kill` still works anywhere via its `or compile_slot()` fallback. A global chord is a command-surface decision, framed separately. - **Two `q` mechanisms coexist by design**: presentation history chains in the side slot (`C → B → A → delete`, Q#BP2c), while `p.prev` prevents raw-switch and capability-fallback listview loops. Neither supersedes the other. - **A capability fallback must strip the QUIT ACTION too**, not just the side parameters — a quit action stranded on a document window makes a later `q` try to restore a presentation that never happened. - **The tree primitive ships — `listview` gained depth, collapse and identity** (P5, §14's last missing workbench primitive; implemented, PR held). Rows carry **optional** `depth` and `id`; absent, a row behaves exactly as before, which is what leaves the flat consumers untouched. The LSP outline is the one adopter. Durable facts: - **Folding is local projection state, not a refresh protocol.** Collapse only *hides* rows and never changes a surviving row's depth, and consumers emit parents before children, so descendants are a **contiguous run**. The primitive therefore re-renders from its own array **without calling the consumer** — which is the only reason the anchor consumer works, because **the outline has no `on_refresh` at all**. A design requiring the consumer to re-supply rows on every fold would have fitted no existing consumer. - **Identity is consumer-supplied and the primitive never derives one**, but it is **not opaque**: `row.id` must be a **string or number, unique among rows, and not NaN**, enforced by `check_ids` where rows enter (`open` and `refresh`). Review narrowed this from "opaque, compared by equality", which was **two contracts wearing one name** — selection compares with `==`, honouring `__eq`, while collapse state stores ids as **table keys**, and Lua indexes tables by raw identity consulting no metamethod. A table id satisfied one half and silently failed the other. Uniqueness and not-NaN came from the same pass: every lookup resolves to the **first** match, so a duplicate makes selecting the later row toggle the earlier, and `0/0` is a `number` Lua refuses as a key. The outline uses `line:col`, because the `::` parent chain collides on overloads and same-named siblings — exactly where a stale expansion would reattach to the wrong node. **Selection is re-seated by id, not by line**, since a fold inserts or removes rows above the cursor. - **`item` is optional in the API and was mandatory in practice.** `line_to_item` is sparse when a row omits it, and `seat_cursor` took `#` of that map — a display-only tree stranded the cursor on the header. It counts visible rows explicitly now. Every existing test supplied `item`, so none could reach it. - **`has_children` must read the FULL row array, not the rendered subset.** A collapsed node's children are absent from the rendered map by construction, so asking the view would answer "no" for every collapsed node and make expanding impossible — a self-sealing bug that looks like fold working and unfold silently not. - **A bite that passes validates the pair, not the test.** The first byte-identity injection used `row.depth or 0`; flat rows have no depth, so it changed nothing and the test "passed" against a regression the flat path is immune to. Ask which defect you injected before believing a green bite. - **pmacs is installable without cloning — Distribution Stage 1, #211, released as v1.1.0.** A `v*` tag builds `pmacs` and `pmacs-gpu` on pinned `ubuntu-22.04` / `macos-15` and publishes a GitHub Release with `SHA256SUMS`. **Journey step 1 works for the first time**, and `COHERENCE.md` §17 moves missing → Partial. Scope was deliberately binaries-only; channels, update, rollback and signing are stated non-goals. Five durable facts: - **A release build can produce FIVE binaries and three must never ship.** Cargo auto-discovers `src/bin/*.rs`, so `pmacs-audit`, `pmacs_fake_lsp` and `pmacs_fake_mcp` appear alongside the two real ones. Exclusion is **two-layered** — explicit `--bin` targets *and* an explicit staged asset list — and layer 2 is not belt-and-braces: building the branch, `target/release` still held all three from an earlier `cargo test --release`, and `Swatinem/rust-cache` restores exactly that in CI. **Archiving `target/release` would have published a fake language server.** - **`env!("CARGO_PKG_VERSION")` expands in the crate being COMPILED.** `InstanceIdentity::for_running_process` lived in `pmacs-protocol` and read it there, so the daemon reported the *protocol* crate's version to every frontend under a field named `pmacs_version`. Three tests asserted the right thing and **could not fail** while both crates read 1.0.0 — diverging them is what made the tests discriminating. *A test can be correct and still prove nothing when the two things it compares are equal for an unrelated reason.* - **Pin release runners, never `-latest`.** `ubuntu-latest` (glibc 2.39) silently produces binaries that fail to load on Ubuntu 22.04 and Debian 12; `macos-latest` drifts the minimum supported macOS with no commit to point at. And **a pinned runner proves nothing about the artifact** — the glibc floor is asserted by reading versioned symbols out of the binary (`objdump -T | grep GLIBC_`), so a bad runner change fails in CI instead of shipping. - **A tag pushed before its workflow is on the default branch does nothing, silently.** `on: push: tags` resolves the workflow file at the tagged commit, and GitHub registers workflows from the default branch. No run, no error — indistinguishable from "not started yet", which is the worst possible shape for a release step. Confirm a run actually appeared. - **Verify a release from the DOWNLOADED artifact, and use a negative control.** Checking CRDT presence by counting `loro` strings means nothing without building a non-CRDT binary and getting zero. - **CI runs the CRDT half of the corpus for the first time — #209.** `.github/workflows/ci.yml` had never enabled the `crdt` feature, so every `#[cfg(feature = "crdt")]` test was **not compiled** — not skipped, not filtered, not reported. **279 tests had never executed in CI, 186 of them in the library**, behind the `cargo test --lib --features crdt` invocation `CLAUDE.md` lists as a **required** pre-PR gate: a required gate CI had never run. `Test (crdt)` now runs 3,766 tests, `M10 Perf Gates (crdt)` covers two suites no workflow had named, and `clippy --features crdt` is enforced. **275 of 279 recovered**; the other four are excluded with stated reasons. Five durable facts, each of which contradicted something previously recorded: - **`gpu-render` runs a DIFFERENT PACKAGE** (`cargo test -p pmacs-gpu`) from the root-package GPU suites. The long-recorded fix shape — "move the GPU-requiring crdt suites onto `gpu-render`, it already has lavapipe" — does not work as written. One job covers the whole corpus instead, which also cannot develop the hole splitting invites: a suite added later would otherwise land in the job needing no GPU and skip there forever. - **`PMACS_REQUIRE_GPU` is not uniform.** Present in `vterm_stage3_acceptance` (×2) and `bottom_panel_stage2b_gpu_ acceptance` (×1), **absent entirely** from `gpu_invocation_ acceptance` and `gpu_initial_target_acceptance`. It cannot serve as blanket proof the GPU suites ran. - **`m10_10_perf` is a CI-default regression tripwire, not a bench.** Its header says its bounds are "generous … to catch catastrophic regressions, not to verify a tight perf claim", so the *absence* of `#[ignore]` is the design. Giving it a perf job would have shipped a coverage reduction inside a coverage lane. Classifying the three `_perf` suites by filename and marker counts got the one whose name disagreed with its purpose exactly backwards. - **`--keep-going` is what turns a clippy run into an inventory.** Clippy abandons remaining targets at the first failure, so any un-`--keep-going` list is a lower bound. The recorded seven-item list was stale in *both* directions: one finding had been fixed incidentally, one was new, and every line number had moved. - **A feature can matter to a crate a per-test census scores as unaffected.** `pmacs-protocol`'s `crdt` feature gates no tests — 17 either way — but changes `cfg!(feature = "crdt")` *expressions* inside the capability defaults, so the same tests exercise different runtime values. Worse, the crate's only use of those defaults was a **transport round-trip, which is invariant to the values**: an all-false default passes identically. Running code is not testing it, and that gap survived the first review round. - **Two arcs completed in that run, and their lanes are gone from `docs/active-work.md` accordingly** (rule 4 removes a lane once its arc is done *and* its facts are here): **Journey Stage 1** — 1a plus the whole 1b split — and **test ambient-root isolation**. Discovery and reap-ledger merged a stage each and keep rewritten lanes. ### 1a. Outstanding work — the whole board, 2026-08-01 **Read this before picking anything up.** It is the only place the remaining work is enumerated in one view; the per-arc bullets below give the detail. Nothing here is in flight: **zero PRs are open** at this anchor, so every item is startable. #### Arc state, against `COHERENCE.md` §20's priority order | P | Arc | State | What is next | |---|---|---|---| | 1 | **Journey** | **Stage 1 COMPLETE** (1a #182/#183; 1b-1 #203, 1b-2 #204, 1b-3 #205) | Journey runs to step 10. The thin end is now steps **1** (install — that is P8), **11** (background work: visible but no ownership model, §9) and **12** (session restore: desktop-save is opt-in *and* a documented no-op under a daemon) | | 2 | Workspace + location | Missing; model gap | The long-lead arc. Start before a fifth subsystem grows its own root convention — four have already diverged (§7) | | 3 | Extension ownership | Missing; prerequisite-shaped | **`pmacs.hook.remove` does not exist.** That one bug-sized gap blocks §13's disable/uninstall, §10's trust classes, and package-scoped cancellation | | 4 | **Discovery** | **Stage 1 MERGED (#207)** | Stage 2 candidates, in rough dependency order: richer M-x rows (**protocol change** — `MinibufferPrompt.candidates` is `Vec`; `CompletionPopupRow` already proves the pattern), `Command` gaining title/category/aliases/flags/arg-schema (~147 definition sites), predicate evaluation, help-layer unification, and the help-prefix decision | | 5 | Workbench convergence | Partial; **Arc 7 COMPLETE** (#213) and **the tree primitive is implemented** (PR held) | The bottom panel is finished on both frontends and the adopter default is flipped. The tree primitive has landed on a held PR: §14's Tree moves ✗ → ◐ with the LSP outline as its one adopter. **Next: adoption** — dired's `i`, then DAP's variables view, which is why it was built first | | 6 | Config productization | Foundation only | Value provenance, then layering, then adoption migration (**table-valued settings are the hard prerequisite** — `ConfigValue` is four scalars) | | 7 | Package lifecycle | Not started | Correctly sequenced after P3 | | 8 | **Distribution** | **Stage 1 SHIPPED (v1.1.0, #211)** | Binaries on tag, checksums, machine-checked glibc floor. **Journey step 1 now works and the "invisible until this exists" blocker is lifted.** Next is a *decision* about channels / update / signing, not a queued plan | #### Open lanes (branch exists, work not finished) - **CRDT half of the corpus is dark in CI — FIXED, merged as #209.** Now a lane kept only for three follow-ons (macOS leg, the `--lib --features crdt` flake, the `crdt_replica` serde divergence). See the arc bullet in §1. **Re-measure before quoting a number**, and there is now a tool: `scripts/feature-census luajit luajit,crdt`. Measured 279 dark at `4223dd3`; 275 recovered, 4 excluded with stated reasons. Two corrections it forced are worth carrying: **`m10_10_perf` is a CI-default regression tripwire, not a bench** (its bounds are deliberately generous, so `#[ignore]`ing it to give it a perf job would *reduce* coverage), and **`gpu-render` runs a different package** (`pmacs-gpu`) from the root-package GPU suites, so the long-recorded "move them onto gpu-render" fix-shape does not work as written. - **Generated-buffer immutability** — Stage 1 merged (#191); Stage 2 not started. Four writer mechanisms have still not adopted `set_generated_contents`; key the inventory by *writer*, not buffer. - **Bottom panel** — Stage 2 complete; Stage 3 is the adopter default flip. - **Folding** — Stages 1–2 merged; Stage 3 (GPU) next, with mirror-clear-on-snapshot a named obligation. - **Reap-ledger** — diagnostic merged (#202); every *disposition* change is still parked (below). - **Kill-ring browser + persistence** — parked by choice. #### Deferred work, by the framing that parked it Each was a deliberate decision with a stated reason; none is a to-do someone forgot. - **From LSP guidance (#204):** build `pmacs.error` (**fifteen guarded call sites reporting through a channel that does not exist**); promote the spawn-failure record into Rust's status model so `*lsp*` shows failures natively; surface `LspEventKind::Crashed` — a server that *started then died* is unsurfaced and is a different message. - **From the welcome (#205):** the help prefix — **`C-h` is not free**; it deletes a word because non-kitty terminals cannot disambiguate Ctrl+Backspace from Ctrl+H (both byte 0x08), so rebinding breaks Ctrl+Backspace on every legacy terminal. Also: make `show_help_text` adopt the generated-buffer write invariant; onboarding proper (§18's ten-step sequence). - **From discovery (#207):** everything in the P4 row above, plus settings **value provenance** (§11) and **closed-set acceptance semantics** — completion today is *assistance*, not validation: `resolve_accepted_value` returns the literal typed text when no candidate is selected, so a typo still reaches the handler. - **From the reap ledger (#202):** Q#RL1's strict-`ESRCH` probe and Q#RL2's retry policy — **neither can move alone**, because `shutdown()`'s loop exits when the ledger empties, so a strict probe without a loop change converts a silent early exit into a guaranteed 2 s stall at every editor exit. Also parked: retargeting to the measured pgid, `signal_target`'s read-then-kill of `tcgetpgrp` (the "most likely real fix site"), and **why** a group-directed `kill` returns `EPERM` against a live owned child — still unknown. - **From ambient isolation (#206):** production still resolves ambient roots by default (only *construction* gained a parameter); nothing audits what previously wrote into `~/.local/share/pmacs`. #### Side quests and standing hazards - **`pmacs.error` is undefined in production.** Fifteen `if pmacs.error then` guards make the silence look deliberate. Report through `pmacs.editor.set_status` until the channel is built. - **Judging a red CI run: `docs/ci-red-signatures.md` is the authority.** It keys on **signature**, not test name — a failure in a listed test that lacks that row's fragments is a NEW incident, not a known one. The old rule here ("rerun before concluding") is retired: **a green rerun establishes intermittence only**, never environmental cause or harmlessness; the same signature again is a second occurrence and stays blocking. One row is an **unresolved possible product defect** that no rerun can clear. This list previously named three tests. The audit found one of them had produced **two distinct signatures** with different causes, and that two of the four incidents actually seen were absent from it — which is why name-keyed lists are not trustworthy. - **`basedpyright` hangs forever** — always `cargo test --test m4_acceptance -- --skip basedpyright`. - **INCIDENT — the crdt sweep's missing build step. §3 now owns this requirement; what stays here is the history and the signature.** Signature: twelve `gpu_invocation_acceptance::crdt::*` failures, each *"build pmacs-gpu before this acceptance suite"*, on a target directory with no `debug/pmacs-gpu` in it. Seen on **PR #228's first gate run** (2026-08-09) — the first `--protocol` run in a *fresh* per-worktree target directory after #225. Latent for the whole life of the shared `CARGO_TARGET_DIR`, which nearly always already held the binary, so the precondition was met by accident. Reproduced deliberately the same day on a disposable cold target: default sweep exit 0, crdt sweep exit 101 with exactly those twelve. **`scripts/gate --protocol` now runs the build as a named `build-crdt` step**, so this signature appearing again means the script was bypassed, not that the requirement moved. The invocation, the measurement and the reasoning are in §3. - **A shared `CARGO_TARGET_DIR` makes concurrent sweeps unattributable.** Every worktree on this machine resolves to the same target directory, so `target/debug/pmacs` is a **shared mutable file**: a `cargo test --workspace` at default features in one worktree overwrites the binary a running `crdt` sweep is spawning, and every real-daemon suite then starts the wrong one. **Established once, on 2026-08-05, in the Stage 2 hardening sweep** — seven failures across three real-daemon suites against a clean baseline, the failure text naming its own cause (*"start the daemon built with the `crdt` feature"*), `pgrep` confirming the rival build, and a re-run from the same tree with a **dedicated** `CARGO_TARGET_DIR` giving 41/41. The reciprocal case was seen from the other side the same day. **Give a second worktree its own target dir**, check for live worktrees before believing a sweep failure, and treat any red from a sweep that overlapped another build as unattributable rather than as evidence. *(This mechanism does NOT retroactively explain the tree lane's unclassified occurrence — that one's signatures were destroyed before being read, so it has no captured text to match against this one's, and it keeps two non-causal hypotheses. A mechanism established in one occurrence is not evidence about a different occurrence that was never characterized.)* - **A local sweep leaks daemons, and they accumulate across days.** `gpu_invocation_acceptance`'s one-command tests leave ~3 orphaned `pmacs --daemon` processes per sweep, reparented to systemd with deleted sockets; 42 were resident at one point, the oldest four days old. They are a rival explanation for any load-sensitive local failure, so **check `pgrep -f "pmacs --daemon"` before trusting a local red**. Lane recorded in `docs/active-work.md`. - **A `PROTOCOL_VERSION` bump's blast radius is every version-sensitive test, and NONE of them appear in the diff.** Long-lines Stage 3 bumped v21→v22 and broke **eight** version assertions across six suites. CI showed exactly **one**, because **cargo stops at the first failing target**; the rest surfaced only afterwards, and one at a time would have cost four more red rounds. **The first thing to say is that §3's gate list would have caught it.** `cargo test --workspace -- --skip basedpyright` is in that list and was not run — `CLAUDE.md` carries a shorter list ending at "the touched acceptance suites", and that shorter list is what the lane followed. **When the two disagree, §3 is the authority**; the short form is a summary, and a summary of a gate suite is not a gate suite. **But §3's sweep alone would still have understated it**, which is why this bullet exists rather than just a pointer. Plain `--workspace` stops at the first failing target and builds one feature configuration, so it would have shown one or two of the eight. §3 now carries the strengthened form: **`--workspace --no-fail-fast -- --skip basedpyright` in BOTH configurations.** **Note `--workspace`, not `--tests`** — the lane's own remediation sweep used `--tests`, which silently drops the `pmacs_protocol` and `pmacs_gpu` targets. On a *protocol* bump that omits the protocol crate's tests, which is how a correction can reproduce the shape of the mistake it is correcting. **Sort the failures before fixing them.** A *tripwire* (`assert_eq!(PROTOCOL_VERSION, N)`) is meant to fire and takes a deliberate edit; three of the eight were these, and the one pin that must NEVER be edited — `ADVERTISED_PROTOCOL_VERSION == 20` — did not fire. The other five were defects sharing one shape: **an absolute contract expressed as arithmetic on, or equality with, a moving constant.** `PROTOCOL_VERSION - 1` for "below the panel version"; `PANEL_MIN_VERSION == PROTOCOL_VERSION` for a coincidence true only while panels were newest; `PROTOCOL_VERSION == 21` standing in for the panel stage's own version; `"21"` for a negotiated session version. Anchor on the constant the contract *names* — `src/` already spelled it `PANEL_MIN_VERSION - 1` in five places, and every outlier was in `tests/`. - **A local sweep is blind to whichever feature configuration it does not build.** Stage 3's census and every verification sweep ran `--features luajit` WITHOUT `crdt`, so no crdt-gated suite was exercised and `compile_mode_crdt_acceptance` reached CI broken. Sweep BOTH configurations before claiming a corpus is green — the crdt job exists precisely because that blindness is easy. - **"My change made this fragile" is a different finding from "this was always flaky", and only one of them is yours to fix.** Stage 3 saw two CI runs on one commit fail DIFFERENT PTY/GPU suites — the load-sensitivity signature, on suites the flake list already names. The tell that it was neither: the failures kept landing on GPU *terminal* tests, and terminal placement was what the PR changed. Those fixtures opened with no `display`, so the flip shrank the very window whose rendered frames they assert against. **Ask which tests and why those, before reaching for a rerun.** - **Never hand-roll the dark-test census — use `scripts/feature-census`.** libtest prints `name: test` with **no space before the colon**, so a filter written `/ : test$/` matches nothing and reports a clean zero; a target with zero tests prints its `Running` line and nothing else, so counting only test lines drops it from the diff; and both configurations need an `--ignored` pass, or pre-existing ignores get attributed to the feature. Each of those was hit while writing the script, and the second one survived two revisions of a framing doc. - **A green a37 means nothing on its own** — the vterm real-daemon acceptance returns `ok` without running unless `pmacs-gpu` is built. - **Previous anchor, retained for provenance:** `4cd4a7b` (the generated-buffer immutability framing #188, the resource-op delete-guard implementation #190, silent-skip arming #192/#193/#194, CI timeouts and concurrency #195, the process teardown stdin-deadlock fix #197, dired Stage 2a #196, generated-buffer immutability Stage 1 #191, and bottom-panel Stage 2B-3 #198). - **Previous anchor, retained for provenance:** `6c9e765` (the dired Stage 2 framing #171 and the resource-op delete guard framing #186 — both framing-only, no runtime code, no implementation started — atop the docs-only coherence listview correction #189, atop the docs-only landed-state refresh #185, the M4 config-sink race fix #174 — test-only — atop bottom-panel Stage 2B-1 #184, the Journey/GPU directory-target ratchet #183, Journey Stage 1a #182, incorporating terminal configuration + copy mode landed docs #180, Lean 4 Stage 4b #181, the dired Stage 1 landed docs #169 and the PTY-terminate diagnostic #176, terminal copy mode #178, the GPU-terminal-input landed docs #168, Lean 4 Stage 4a #179, bottom-panel Stage 2A #177, the bottom-panel Stage 2 framing #175, terminal configuration Stage 1 #173, Lean 4 Stage 3b #170, Stage 3a #167, the CRDT undo repro #157, the inline-math landed-doc refresh #172, the bottom-panel landed-doc refresh #156, the inline-math slice #158, dired Stage 1 #165, the GPU terminal input fix #166, Lean 4 Stage 2 #161, the dired framing #164, COHERENCE.md #163, find-file #162, Lean 4 Stage 1 #160, minimap blank-slab #159, bottom-panel Stage 1 #155). **Protocol schema support is `v6..=v21`, the production server-first `Hello` advertises v20, and a session at that anchor nevertheless negotiates v21.** All three are true at once, and Stage 2B-3 is what made them compatible: the advertised version is a permanent **baseline** and the session's real version is settled one message later by the frontend's `AttachRequest` counter-offer — a mechanism that is still current, independent of which numbers it carries. The bullets below describe the arcs in their own terms. **These statements describe the historical `6c9e765` anchor; the live protocol range is recorded under "Repository authority" in `docs/active-work.md`** (`v6..=v22` since #221 added `LineWrapFacts`; the advertised baseline is still v20). This line previously called itself "the head-of-`main` anchor", which stopped being true at #219 — so a provenance note read as a current-state claim, and disagreed with the anchor at the top of this file. - **`COHERENCE.md` is now required reading and a required framing input — #163.** It carries the product-coherence thesis, an audited scorecard, per-concern gaps, and §20's priority order, and it is the standard new work is evaluated against. Per `CLAUDE.md`, **every new framing doc must state its coherence impact** — journey steps touched, interaction islands added, config-registry adoption, background-work attribution. Its §2 grades the golden journey; **Journey Stage 1a moved that grade off "broken at step 3"** — see the arc bullet below. - **Journey arc (P1) — Stage 1b-1 LANDED (#203)** (`docs/journey-stage1b1-compile-defaults-framing.md`). Journey step 9 moves **Partial → Works**: `C-c c` runs `compile.run`, and the first prompt is prefilled from the detected project kind via `pmacs.compile.defaults` (seeded `rust = "cargo build"`, extensible from `init.lua`). Lua, tests and docs; no Rust change, no protocol change. The ratchet now carries steps 2, 3, 5 and **9**. - **Sharing a resolver is not capturing one.** `pmacs.minibuffer.read` is asynchronous and nothing freezes the active window while a prompt is open, so having the prompt and `compile.run` call the *same* cwd resolver still let them disagree: the user could be offered `cargo build` for A and given a run in B by clicking away mid-prompt. The interactive command captures `pmacs.compile.context()` once and passes its `cwd` through to the run. **This is Stage 1a's `commit_to` lesson on a smaller seam** — capture at request time, never re-derive when the async work lands. Review found it; the first framing had the weaker design and said it was sufficient. - **A pin that never crosses the accept boundary cannot see that class of bug.** Every originally-proposed pin compared values the prompt and the resolver already agreed on, so the defect above passed all of them. Two pins now accept the prompt and observe a real process. - **`ProjectKind::Cargo` does not exist** — `COHERENCE.md` named it twice, citing `src/project.rs:77`, which is the *doc comment*; the variant on line 78 is `ProjectKind::Rust`. Lua never sees the variant anyway: `pmacs.project.detect` returns the tag string `"rust"`. Corrected in both COHERENCE sites and recorded in its §24. - **The compile fallback cwd is the process cwd, which under `cargo test` is the pmacs repo — itself a Cargo project.** Any pin asserting the *absence* of a Cargo suggestion that reaches the fallback reports pmacs's own `Cargo.toml`. Bite D confirmed it: with the kind derived from the process cwd, the plain-fixture prefill pin still passed and only the nested-project pin caught it. `set_search_boundary` is no defence — it clamps only a walk starting *below* the boundary. - **Named limitation, deliberately unfixed:** after `pmacs ` the active buffer is dired's and **pathless** (`pmacs.buffer.create` assigns no path; dired compensates through its own module-local `handle_for_buffer`), so the cwd falls through to the process cwd. Launched from elsewhere that is the wrong directory. The fix is §8's execution-location model, not a reach into dired's private table. What is guaranteed is that the failure stays *coherent*: the suggestion always describes the directory the run will use. - **Journey arc (P1) — Stage 1a LANDED** (`docs/journey-stage1a-framing.md`). `pmacs .` opens a directory instead of exiting 1, on **one** path: `resolve_target_buffer` gained a `ResolvedTarget::Directory` arm *ahead* of the load, `EditorState::open` became a caller of it rather than a parallel implementation, and the daemon/GPU bootstrap shares the same arm. Which surface handles a directory is the `path.open-directory` chain with dired as a replaceable fallback slot. `tests/journey_acceptance.rs` is the new cross-subsystem ratchet (steps 2, 3, 5 seeded; **stages add rows, none removes them**). No protocol change. - **A hook a builtin subscribes to can never be first-claimant-wins for users.** `HookRegistry::add` only appends and builtins load before `init.lua`, so a dired subscription would always claim before any user listener. That is why dired is a *slot* (`pmacs.path.directory_handler`) and not a subscriber — and why clearing the slot has to leave startup succeeding with a status, not exiting 1. - **A raise and a `false` are indistinguishable in `proceed`.** `run_short_circuit` returns `proceed = false` for both; only `HookOutcome.errors` separates them, and it decides whether to *report*, not whether to fall back. Getting this backwards produces a fallback that runs after a user's resolver crashed mid-handling. - **The listing is async; the bootstrap is synchronous.** The whole post-await commit therefore runs against a destination captured at request time (`pmacs.window.commit_to`), which preflights every precondition *before* invoking the callback — dired mutates handle state, `prev`, and paint long before it reaches anything that could refuse, so validating at display time is four mutations too late. Awaiting inside a commit is refused: a yield would restore the scope while the coroutine is still parked. - **The scope swaps `core.active_frontend`, not just an override** — `pmacs.window.buffer()`'s no-arg arm reads the ambient active buffer directly, so dired's `prev` capture would otherwise follow whatever frontend happened to be dispatching. The override *also* exists, and is load-bearing in exactly one case: a commit reached from inside an interactive command, where the origin would otherwise outrank the ambient value. Bite-testing found N4 green without it. - **`replace_active_buffer` does not drop the startup scratch buffer**, despite its doc comment having claimed so for as long as it has existed. Its body is one `switch_active_buffer` call. The comment is corrected here; changing the lifetime is separate work. - Stage 1b is the named remainder: compile binding + Cargo defaults, LSP spawn guidance, welcome buffer. - **Terminal configuration + copy mode arc — COMPLETE** (`docs/terminal-config-and-copy-mode-framing.md` rev 4; Stage 1 #173, Stage 2 #178; no protocol change in either, still v20). Stage 1 ships profiles, scrollback, a per-terminal configurable escape key and the `C-c t` opener; Stage 2 ships copy mode — `M-x terminal.copy-mode` / `C-c C-t`. - **The snapshot MATERIALIZES into an ordinary buffer.** That is the arc's organizing decision: isearch, motion, selection and the kill ring work with no new substrate, and "keys must not reach the child" dissolves structurally, because the transport arm keys on `is_terminal(buffer_id)` and a snapshot is not a terminal. **The dispatch-shadow count therefore stays at six.** - **`prune` reacts to buffer removal rather than causing it** — it filters on `!registry.contains(buffer_id)`, so a child exiting does **not** remove the terminal buffer. That is what makes `on_removed` a sound teardown hook, and why a finished command's output stays readable. - **Ownership means "in our own handle table", never found-by-name** (dired's F7 rule, re-learned here): snapshot writes use `bypass_intercept`, so adopting a same-named foreign buffer clobbers user data. Snapshot identity is keyed by **comparing buffer handles in an array** — `BufferIdLua` implements `__eq` but each wrapper is a distinct table key, so comparison works and hashing does not. - **Profiles are a raw Lua table**, joining `pmacs.lsp.config` and `pmacs.pair.sets`, because `ConfigValue` is four scalars with no table kind. The two open-time settings resolve through the **global** chain (they are read before the identity buffer exists); only `terminal.escape-key` resolves per buffer, and its cache lives on **`TerminalSession`** so its lifetime is the terminal's — `value_epoch` alone is not a sufficient key, because it does not advance when focus moves between terminals holding different buffer-local values. - **Criterion 17 is deliberately unpinned, and its bite is now stated correctly.** A real semantic frontend proving neither copy is mutated needs the actual GPU binary (the optimistic apply exists only in `pmacs-gpu/src/main.rs`; the headless `SemanticClient` has no optimistic path), i.e. the `a37` footing §5 warns about. After `set_generated_contents` the eventual test must look for **unauthorized mirror mutation plus daemon refusal — divergence**, not the "mutates both sides silently" the criterion originally specified, which can no longer happen and would pass for the wrong reason. *A fix can invalidate a test that was never written.* - Test instruments worth reusing: **`cat -v` is the echo probe**, because the screen rejects C0 controls before they reach cells so a raw echoed `Ctrl-X` is invisible; and such probes must **count occurrences rather than test presence**, because a single-character probe collides with the child's own banner text. - **PTY terminate diagnostic LANDED — #176** (merge `bf8878f`, 2026-07-26, one review round; `docs/process-signal-tolerance-framing.md` rev 4, after three framing rounds). **Diagnostic only — no disposition changed.** Every call that failed before still fails, with no state transition and no reap-ledger arming; `src/process.rs` is the only source file touched. It exists because the `terminate` EPERM flake is real and nothing yet knows *why*. - **Why three tolerance rules were all rejected: each concluded something about a process from something that was not about that process.** Rev 1 reasoned from an errno alone (EPERM means the caller lacks permission, not that the id was recycled); rev 2 from `try_wait`, which observes the spawned **leader** while a PTY signal targets `-tcgetpgrp(...)` — entities that diverge exactly when job control has moved the terminal; rev 3 from group-directed **ESRCH**, which proves only that the selected foreground group vanished. This is the reusable shape, not a Unix trivium. - **Two facts that killed the original argument.** `group = true` is *rejected* for PTY mode at spawn, so the reap ledger never applies to the PTY path at all; and the ledger's own comment saying EPERM "cannot happen for our own children" drops the entry for **bounded growth**, not as a ruling that EPERM means dead. A comment stating a belief is not the same as code enforcing it. - What ships: a failing `kill` now reports five separate facts — target source, target kind/value, spawn-time group, errno, and the leader's real `try_wait` state. The test seam injects the **kill result only**, never the observation, so the real `ChildHandle::try_wait` runs against the real child. - **It is not "strictly additive".** `try_wait` reaps and caches, so an exited child may be reaped earlier than before. That is safe only because `portable-pty` 0.9.0 returns a `std::process::Child` on Unix and delegates `try_wait` to it, so `poll_one` still sees the cached status — pinned by an exactly-one-terminal-event test rather than assumed. - **Still open, and still the most likely real fix site:** `signal_target`'s read-then-kill of `tcgetpgrp`. All tolerance rules remain parked pending the evidence this diagnostic produces, as does `terminate` idempotence for an already-reaped process (a different failure, so a different PR). - **The diagnostic fired, and what it showed.** macOS CI, PR #191, [run 30553376486](https://github.com/levineuwirth/pmacs/actions/runs/30553376486/job/90907461258): `target=-8619 via group, leader_pid=8619, expected_group=-8619, leader=live` — the `spec.group` pipe path, not the PTY path, with the leader observed alive by a real `try_wait`. A rerun of the identical head passed 12/12, so it is intermittent. - **Owning the child does not license dismissing a group error, and the occurrence does not prove the child received EPERM.** The failed target was the *group* `-8619`; `try_wait` observed the *process* `8619`. Nothing measured `getpgid(8619)`, so the two are not known to refer to the same thing. What is settled is narrower and still enough: a group target computed from the spawn-time `pgid == pid` assumption returned EPERM while the leader was alive, which retires "EPERM cannot happen for our own children" as a reason to discard an arbitrary group-directed error. Attributing the errno to the child would repeat the exact error that killed three tolerance rules — concluding something about one entity from something about another. - **A field named like an observation can be a restatement of its input.** `expected_group` is `-leader_pid`, and on the spawn-group path the target is `-leader_pid` too, so the report printed the same number three times and their agreement was arithmetic. Stage B adds a `measured_group` from `getpgid`, which is the only field able to disagree — and it still establishes no identity, because it is read inside the same read-then-act window and no portable mechanism closes that for a *group* (`pidfd` covers a process; macOS has neither). - **Discovery arc (P4) — Stage 1 LANDED (#207)** (`docs/discovery-stage1-command-family-framing.md`, rev 6, three review rounds). Eleven `help.*` commands over the existing registries, indexed by `M-x help`. **§5 moves substrate-without-surface → Partial.** No Rust: the data was all reachable from Lua, and the settings completion source is a Lua function through `CompletionSource::Custom` — correcting a `default.lua` comment that claimed `source` was a fixed Rust-side vocabulary. - **Completion is assistance, not validation.** `resolve_accepted_value` returns the literal typed text whenever no candidate is selected, so a typo still reaches `on_accept`; and a fuzzy near-miss would silently select a *different* value. Refusing a non-candidate is Rust work, deferred. - **`apropos` is substring, not fuzzy.** `fuzzy_score` is subsequence-based and descriptions are long sentences, so fuzzy matches nearly everything. Pinned by a fixture whose description contains the needle only as a non-contiguous subsequence. - **One owner for `*help*` writes is what the seam buys — not a one-site migration.** `src/help.rs` has renderers for command/key/buffer/mode/hook/view and **none** for settings, lists or apropos, and `_show_help` takes already-flattened text. Rendering is therefore a named per-subject function, so the future Rust work is enumerated per subject (three new renderers) rather than discovered per call site. - **The seam-counting pin caught a real bypass**: the two renamed commands were still calling the file-local `show_help_text`, so the funnel was fiction for exactly the two that predate it. - **`Command.predicate` is still never evaluated** — read only at `src/help.rs:76` and one test. A preservation pin registers a *raising* predicate and asserts the command still runs, so a stage that starts evaluating must change that pin knowingly. - **Journey arc (P1) — Stage 1b-3 LANDED (#205)** (`docs/journey-stage1b3-welcome-framing.md`, rev 4, three review rounds). The last of the 1b split. An unconfigured launch greets in `*scratch*`; `M-x help` renders a cheat sheet. **§18 and the scorecard move Missing → Partial**; §2's step-4 row stays Partial. - **No constructor is the startup hook.** `EditorState::open` calls `new` *before* resolving its target, the daemon constructs one too, `init.lua` runs inside `new`, and desktop restore happens later still. `run()`'s terminal-free prefix is now `prepare_startup`, and the greeting is its last step. - **Extraction is what makes wiring testable.** With the seam called by hand from tests, deleting the production call left every assertion green while shipping no welcome — the "guard with no production caller" shape. `prepare_startup` is `pub` because the journey suite is a separate crate and the rest of the sequence (`run`, `new`, `open`, `install_state_dirs`, `restore_desktop_if_armed`) is already public. - **`C-h` is not free**, and §2's step-4 row used to imply it was: it deletes a word because non-kitty terminals cannot disambiguate Ctrl+Backspace from Ctrl+H (both byte 0x08). Rebinding it to a help prefix breaks Ctrl+Backspace on every legacy terminal. Deferred to the discovery arc **with the reason recorded**. - **Deliberately NOT `set_generated_contents`** — it would lift read-only, discard history and mark the buffer generated, all wrong for a buffer step 5 requires the user to type into immediately. The one place not adopting that invariant is correct. - **`pmacs.command.invoke` is not the M-x path.** M-x is `editor.execute-command`, a minibuffer with the `commands` completion source calling `invoke_interactive` on accept — and because a selected candidate shadows typed text while `accept()` does `session.take()`, the pin asserts `pmacs.minibuffer.selected() == "help"` **before** RET. - **Journey arc (P1) — Stage 1b-2 LANDED (#204)** (`docs/journey-stage1b2-lsp-guidance-framing.md`, rev 4, three review rounds). `COHERENCE.md` §1.2's canonical silence: a preconfigured language server that is not installed now reports with guidance, marks the modeline `LSP:!`, and appears in `M-x lsp.status`. §2's step-6 row **stays Partial** for a reason that landing did not touch: a server that starts and then *crashes* is still unsurfaced. - **`status_buffer_text()` had existed since M4.8, exposed to Lua and tested, with no production caller and no `*lsp*` buffer** — several `src/lsp.rs` and `src/project.rs` doc comments referred to that buffer as though it existed. Half the stage was wiring dark matter. - **The reporting shape was already adopted twice in `lsp.lua`** (root resolvers, notification subscribers). The canonical case was silent because nobody had converted it, not for want of a mechanism. - **A failed spawn leaves NO record**: `LspManager::spawn` returns early before both `status_tracker.ensure` and `clients.insert`, so `pmacs.lsp.list()` cannot see it and the affinity loop re-spawns. The failure therefore recurs **once per file open**, not once per project root as COHERENCE recorded. Hence: **memoize the report, not the failure** — the spawn is still retried, so installing the binary mid-session recovers with nothing to invalidate. - **The affinity key is `(language, key_uri)` and `key_uri` is nil for markerless files**, which deliberately share one server per language. Lua cannot index by nil, so one encoding function serves both tables with a `u`/`n` discriminator no URI can collide with. - **Three tables, three lifetimes.** `reported` (never cleared, includes the command so repointing at another missing executable re-reports); `failures` (cleared on a successful spawn for that key); and a **buffer-keyed projection** for the modeline, because that provider runs for every window on every paint and deriving an affinity key inside it would invoke root resolvers during painting. - **A success must SWEEP the projections, not clear one.** Clearing only the succeeding buffer leaves an earlier buffer rendering `LSP:!` while `lsp.status` reports nothing wrong. - **A new per-buffer table needs its own teardown.** Nothing existing reaches it: the LSP resource reconciliation iterates `attachments`, and a failed buffer has none by construction. `pmacs.buffer.on_removed` is registered once per projection; rename and delete **clear** rather than re-key, because after a rename the failure is no longer known to apply at the new location. - **Reap-ledger silent failures — DIAGNOSTIC, in flight** (`docs/reap-ledger-silent-failures-framing.md`). The lane #200's framing §5 parked and its evidence unparked. **Four `kill(2)` results are discarded in the group reap ledger**, and each discard has its own consequence — three in the persistent ledger, one in the in-drain twin: - `tick_reap_ledger`'s probe cannot tell `ESRCH` (the group is gone — correct) from any other errno (we could not ask — not correct), and `retain` deletes the entry either way, cancelling escalation. - The deadline escalation sets `killed = true` whether or not the `SIGKILL` landed, so **no later tick retries it** — that arm is guarded by `!entry.killed` and never fires again for the group. - `shutdown()`'s force-kill discards its result the same way, on the path written specifically to stop a leak at editor exit. **It is not the same failure**, and the difference is the retry: `shutdown()` iterates the ledger with *no* `!entry.killed` guard, so it does re-kill an entry the escalation arm marked. A failed escalation leaks the group until editor exit, where one more attempt is made; a failed force-kill leaks it *past* editor exit, with nothing left to try. Saying the escalation is "never retried by anything" collapses the two. - `final_drain_runtime`'s twin collapses every errno into "dead", which quiesces the drain and **cancels the readers** — truncated output rather than a leaked process, and terminal for that drain where a later tick could revisit the ledger. - **None of the four has been observed to fire.** #200's evidence is an explicit `SIGTERM` failing in `signal()`, not any ledger call. What it retires is the *reason* ("EPERM cannot happen for our own children"), not the behaviour. - **`shutdown()`'s loop exit depends on the silent drop, and this is now measured.** It runs while `any_running() || !reap_ledger.is_empty()`, so an early exit needs the ledger empty **and** no live managed record — the leader-exited-survivor case the ledger exists to serve. With a failed force-kill followed by an errored probe it exits in under 500ms instead of holding its 2s bound, having concluded cleanup finished because the probe failed. Making the probe strict without touching the loop converts that silent early exit into a guaranteed 2s stall at every editor exit that hits it: **the two cannot be changed independently.** - **There is no channel for a background tick to report on.** `ProcessEvent` is keyed by `ProcessId`, while the ledger is keyed by pgid and is deliberately independent of managed records, so in the case that matters there is no id to attribute to. Every production consumer polls `take_events(id)` per known id; `take_all_events` would sidestep the keying but **has no production consumer at all** (two test call sites only). `pmacs.error` is dead. Reporting is therefore its own lane, as the framing's Bet 4 anticipated. - **A test seam for a background loop has to be directed.** `shutdown()` signals every managed process before it reaches its ledger force-kill, so one undirected "next kill fails" slot is eaten by the wrong call and the test passes while proving nothing. The persistent sites take a FIFO each (the coupling pin needs two outcomes pending at once); the in-drain site needs one outcome that **repeats for a whole drain**, because a one-shot is consumed by the next 1ms probe and can never survive the 50ms window `quiesced` requires. - **An absence assertion needs a fixture that could have produced the thing.** The in-drain pin's first fixture had no `trap '' TERM`, so `poll_one`'s leader-exit group TERM killed the descendant before it wrote its late marker: the marker was absent on *both* paths and the pin would have stayed green with the collapse fixed. The bite caught it — the reverted seam failed only the consumed-plan check, not the content assertion. That is what the consumed-plan check is for. - **Lean 4 arc (Arc 8) — stages 1, 2, 3a, 3b, 4a, 4b ALL LANDED** (`docs/lean4-mode-framing.md`; #160, #161, #167, #170, #179, #181). pmacs edits Lean 4: `arborium-lean` highlighting, a `lean4` major mode, `⟨⟩ ⦃⦄ ⟮⟯` pairs, and a `lake serve` language server with a Lake-aware outermost root, a lazy toolchain probe, a one-shot `lean --server` fallback, and `waitForDiagnostics`. **No protocol change in any stage** (still v20). - **Two of the four stages contained no Lean at all**, and that is the arc's organizing rule: *no PR mixes a cross-cutting substrate change with Lean feature content.* Stage 2 made LSP server affinity per-project-root (`ensure_server` had been reusing one server across roots — a correctness bug for every language, not just Lean). Stage 3a added notification/response subscription seams to `handle_server_requests`, the single shared LSP event drain, plus `pmacs.fs.canonicalize`. - **Two consecutive re-scouts found that rule broken by the stage being scouted** — Stage 3 in round 4, Stage 4 in round 5, each time by a risk column that contradicted its own prose. The rule is not self-enforcing. Re-check every remaining stage's risk column at scout time. - **A configured LSP root must be a canonical absolute path.** It reaches `file_uri_for` verbatim and that URI is the affinity key, so one package opened by two spellings spawns two servers. Stage 3a's `pmacs.fs.canonicalize` is the primitive; it returns nil rather than a lossy path for non-UTF-8 input. - **`LspManager::stop` on an already-terminal client strands it in `ShuttingDown` forever** — `server_is_live` then counts it live so nothing rebuilds against it, and `forget` refuses it for not being terminal. *Stopping a dead server is what makes it un-replaceable.* Stage 3b works around it by dispatching on state (`forget` when terminal, `stop` when live); merely skipping the call leaves `next_restart_at` armed. The real fix is unframed substrate work. - **`elan` shims lie**: `lake --version` and `lean --version` can both fail ("no default toolchain configured") on a machine where Lean otherwise works, so `command -v lake` is worthless as a capability check. Lean acceptance is fake-server; live smokes must be PATH- **and** success-gated. - Stage 3b took six review rounds, and **the same defect appeared four times**: "the fallback silently doesn't happen," as no re-attach, then re-attach cleared by an unrelated buffer, then satisfied by the very server being replaced, then repairing one buffer while the rest stayed stale. Each fix was locally right; none asked what a *global* config swap invalidates. The durable lesson is to heal at **consumption** — the point where a stale record is handed out — not at the moment of the swap. - **Stage 4a (the typed-edit consumer chain) MERGED as #179** (branch `lean4-stage4a-typed-edit-chain`, framing rev 8; it is part of the main anchor above). It is substrate only: `builtin/runtime/typed_edit.lua` owns the single `buffer.after-edit` subscriber and the single one-shot read, `pair.lua` becomes its first registered consumer, and `tests/auto_pair_acceptance.rs` is unchanged by zero lines (criterion 46, verified at the diff). No protocol change, no Lean content. The three decisions that turned out load-bearing rather than stylistic: consumers are called **even when the record is nil** (three existing auto-pair tests assert the non-event through it, and 4b abandons stale pending state on it); each consumer gets its **own copy** of the record, because pairing reads `rec.char` and a declining consumer could otherwise forge it; and the fan-out iterates a **snapshot**, because a consumer that registers a lower-priority one shifts itself forward under `ipairs` and runs twice. - **Round 8's durable lesson: `run_all_must_succeed` does NOT abort the fan-out.** `src/hook.rs:332` collects each callback's error and continues to the remaining subscribers, marking only the run failed — so an uncontained throw inside a hook subscriber does not stop `lsp.lua` from flushing didChange. Two framing revisions asserted the opposite to justify a `pcall`. The guard was right and the reason was wrong, and by the time review caught it the wrong reason had been copied into a module comment, an acceptance criterion, a test comment, and the ledger. **Correct the source a rationale derives from, not only the sites that quote it.** - **Stage 4b (the Unicode input method) MERGED as #181** (framing rev 9): a vendored 1,855-entry table generated from `leanprover/vscode-lean4@17d1d08` by `scripts/regen-lean-abbrev`, plus a consumer registered on the Stage 4a chain at priority 50, ahead of pairing. **A consumer cannot both edit and let a later consumer act on the same keystroke**: the chain hands each consumer a copy of the record made before any consumer ran, so an edit invalidates every copy still to be used. The expansion therefore runs on a SECOND `buffer.after-edit` subscriber after the chain — which is how a pair character that terminates an abbreviation still pairs (`\alp(` → `α()`). And **deferring work past a fan-out means owning which fan-out it belongs to**: these fan-outs NEST, so a consumer between the expander and pairing that calls `pmacs.hook.run` re-enters the deferred subscriber while the outer chain is still mid-list, and the count that recognises this has to come from a MINIMUM-PRIORITY consumer — the expander is optional (a claim can stop the chain first) and a subscriber beside the deferred one is too late (the nested fan-out finishes inside the outer chain's subscriber). Its other durable facts: the table must stay an ORDERED SEQUENCE (equal-length ties resolve by source declaration order, which a `pairs`-iterated map cannot express); a generator round-trip check must re-read the BYTES ON DISK, because comparing in-memory strings cannot see an encoding applied by the write itself; and an expansion that SHRINKS the buffer must place the point explicitly, or every later self-insert is silently rejected and the editor looks dead. - **Round 9 corrected three approved acceptance criteria** by simulating the state machine over all 1,855 entries rather than re-reading the prose. Four review rounds over the text had not found them, because each named an example that reads as obviously right and is wrong only against the data. - Remaining: stages 5 (goal panel), 6 (`#eval` output channel), and 7 (module hierarchy) are framed but not scouted against current `main`. - **Inline math LANDED — #158** (`docs/inline-math-slice-framing.md` rev 3; merge `5aa9044`). pmacs renders `$…$` as typeset mathematics in the GPU frontend. **No protocol change (still v20); the whole slice lives in `pmacs-gpu`**, because `pmacs-gpu` depends only on `pmacs-protocol` and never on `pmacs` — a core-crate parser would have been unreachable from where rendering happens. - `math_parse.rs` → `math_layout.rs` → a `ChunkSource::MathBox` spacer chunk → per-glyph mini-buffers drawn at the shaped line's real baseline, with fraction rules as quads. Font is bundled Latin Modern Math (~717 KiB) under the **GUST Font License** — not OFL. - **The v0 subset is narrow and deliberately so**: Greek (34 entries), sub/superscript, and `\frac`. Everything else — including relations like `\geq`, fences, big operators, and all display math (`$$…$$`, `\[…\]`) — is a named deferral, and an unsupported command degrades the **whole span** back to source rather than rendering partially. In a real paper most inline spans still show source; that is the designed behaviour, not a defect. - **Math is suppressed while the caret is inside its span**, so editing always sees source. That gate reads the effective caret plus selection endpoints and is fed by three separate refresh triggers; it is the most delicate part of the slice. - Selection and search washes cover the whole box rectangle, not sub-ranges (sub-range washes are deferred). - TUI shows the LaTeX source unchanged. That divergence is recorded against `COHERENCE.md` §16, which audits the "no privileged frontend" rule. - **find-file LANDED — #162** (`docs/dired-framing.md` §10, Q#DR11; merge `2af1ab3`; one review round). `C-x C-f` is the dired arc's **Stage 0**: pmacs previously had no discoverable way to open a file by path — no such command existed and `pmacs.buffer.find_or_open` had no interactive caller. Pure Lua in `builtin/commands/default.lua`, one keymap line, an 8-test dispatch-driven acceptance suite; no Rust, no protocol change. Two substrate facts it documents, both worth knowing before touching any minibuffer prompt: - **Completion over files is flat and cannot be made hierarchical from Lua.** A custom `source` function is called with **zero arguments** (`minibuffer.rs:591`) and runs synchronously outside any coroutine, where `Handle:await()` raises — so it can neither see the input to re-root on nor list a directory. Only the Rust `CompletionSource::Files { root }` can list, and it is single-directory and 1024-capped. - **A selected candidate SHADOWS typed text.** `recompute_candidates` sets `selected = Some(0)` whenever the list is non-empty (`minibuffer.rs:372-377`) and `resolve_accepted_value` returns the candidate over the typed contents (`:564-574`). So free-text accept fires only when the input filters every candidate away — for basename candidates under a subsequence filter, when it contains a `/`. This applies to `M-x` and `switch-buffer` too. Consequences are pinned as decisions, including the hole where a new bare name that is a subsequence of an existing entry opens the existing file, and the empty-input case (`fuzzy_score` gives `Some(0)` for an empty needle and ties break lexicographically, so dotfiles lead). - Also: `get_or_load_buffer` computes a normalized path but **loads from the raw one** (`editor_core.rs:842-856`), so a `~/…` path dedups against an open buffer yet fails to load one that is not open — find-file expands the tilde Lua-side. Loading through the normalized path is a named deferral. - **dired Stage 1 — the directory view — LANDED — #165** (`docs/dired-framing.md` §0, S1-1…S1-12; merge `c8ec8f3`; one review round). pmacs now has a directory surface: `C-x d` / `C-x C-j` open a read-only listing, one buffer per directory named `*dired:*`, with a `dired` major mode whose mode-scoped keymap carries `RET`/`f`, `^`, `n`/`p`, `g`, `q`, `s`. Protocol unchanged at **v20**. **Stage 2 (marks and operations) and Stage 3 (wdired) each still need their own framing**; the frozen fixture shrinks after Stage 3. - **The Rust is confined to two things**: a per-entry-tolerant `read_dir` (`ReadDirTolerance {Fatal, PerEntry}` → `FsDirListing {entries, errors}`), because `read_dir_blocking` fails a whole listing on any of five per-entry conditions and the tolerant wrapper its own module doc delegates to package authors **cannot be written in Lua** (one error value, no partial vec); and `editor_core::normalize_buffer_path` becoming `pub`, exposed as `pmacs.path.canonicalize`. Only non-UTF-8 **names** stay fatal — byte-preserving paths would be needed. The Lua result **shape** keys on `errors.is_some()`, so the bare array the frozen M8.2 fixture consumes with `ipairs` is untouched. - **Exposing a core normalizer beat mirroring it in Lua.** A Lua mirror would have been a second canonical form — the same class of bug as the five tab-width constants (#137). Applies to any future Lua-side path reckoning. - **A fixed-width column must be fixed-width for every input.** The exported `pmacs.dired._layout` (MARK 0, KIND 2, PERMS 3–12, SIZE 13, MTIME 24, NAME 41) is the contract Stage 3 reads offsets from, and `%10d` overflows at ≥10 GB, silently shifting every column right of it. Sizes now fall back to a width-clamped magnitude (K/M/G/T/P/E). - **An ambient action must be gated on the buffer it assumes.** A revert's cursor re-seat settles a tick or more later, by which time the user may have switched buffers; the paint names its buffer and is safe, but seating is ambient. This is the buffer-level instance of the rule below that interactive origin does not survive an await. - **A failure IS an answer — don't probe first.** Kinds are lstat-based in both `read_dir` and `stat`, so nothing in an entry says whether a symlink points at a directory. `RET` tries to list it and treats the failure as the answer; an explicit probe was a second full `read_dir`, so a descent listed twice. - **Unbounded per-entry error collection needs a cap when nothing cancels the work.** A dired listing carries no supersede key, so cancellation was never the backstop the tolerant loop implicitly relied on (`READDIR_MAX_CONSECUTIVE_ENTRY_ERRORS = 1024`). - **This is the first builtin with mode-scoped keys** (#129's first non-detection consumer), which broke the pre-existing `describe_key_identifies_every_default_binding`: it asserted every binding resolves through `describe.key` context-free, which held only while the modes table was empty. It now sets the effective context per binding and explicitly **clears** the mode for global ones, because a leaked mode legitimately shadows a global chord of the same name (dired's `RET` shadows `edit.newline-and-indent`), plus a floor assertion that at least one mode-scoped binding exists. - **A dedicated panel does not carry its dedication across a descent** — the framing expected it to. `display_buffer` never replaces the buffer in a slot dedicated to another one; it discards every side-specific parameter and falls back to the document window (Q#BP3 2.iii), and the exact-window arm errors. Dired does not unpin the user's panel; both arms are pinned. - Smaller facts worth knowing before touching this code: a path-backed buffer's **name is its full path**, not its basename, which matters for any name assertion; `pmacs.buffer.kill` (not `remove`) redirects windows off a doomed buffer first, so `dired.kill-when-opening` kills **after** the replacement is displayed; ownership is checked against the handle table only, never the buffer name; and `C-x d` takes **no** completion source on purpose (with one, `RET` on an empty field opens whatever sorts first, and RET-where-you-are is the gesture the binding exists for — the field is prefilled instead). - Verification at merge: 1,832 default + 2,009 CRDT library tests; dired acceptance 25 + 25 CRDT; the frozen m8_1 10 / m8_2 15 / m8_3 32 unchanged, which is the additivity gate for the `read_dir` change; M4 121; required GPU 155; isolated-`XDG_CONFIG_HOME` workspace sweep 3,205 across 93 suites. 15 claims bite-verified. - Canonical `main` is protocol **v21** (`SUPPORTED=[6..=21]`; v16 = `ThemeFacts`, v17 = `FontFacts`, v18 = `StatuslineSegments`, v19 = terminal frames/events, v20 = the GPU initial-target semantic bootstrap family, v21 = the bottom-panel band family). **`ADVERTISED_PROTOCOL_VERSION` stays 20, permanently, and that is the activation mechanism rather than a hedge** — see the Stage 2B-3 bullet. The rule for every future additive family: advertise the baseline, negotiate up from the frontend's `AttachRequest`. Moving the advertised version is reserved for a change that cannot be expressed additively at all, because a server-first `Hello` reaches a shipped frontend before it can identify itself. - **Bottom panel Stage 1 (window placement + TUI side windows) LANDED — #155** (`docs/bottom-panel-framing.md` rev 4; merge `e745068`; two review rounds). **No protocol change (still v20).** Arc 7's substrate: pmacs now has Emacs's `display-buffer` + window parameters, and a buffer can be displayed in a fixed-height window pinned to the bottom of the frame that feature code targets **by policy** instead of by stealing the selected window. - `src/window.rs`: `WindowParams { side, fixed_rows, dedicated }` plus implementation-owned `quit_action` / `origin_document` (Lua reads them, `set_params` refuses them); `MIN_WINDOW_OUTER_ROWS = 2`; `Layout::compute(area, fixed)` subtracts fixed children before dividing the remainder by weight, preserving last-flexible-takes-the-remainder, so a tree with no fixed leaves computes byte-identically to before. - **`Layout::compute` has TWO production callers**, and both must feed the same shared `panel_fixed_rows` map: `window_placements` and `src/overlay_paint.rs`'s peer-presence pass, which derives its own text-area `Rect` and never routes through the first. Leaving the second on unfixed geometry paints every peer cursor at the row it would occupy with no panel open. - **The minimum is recursive** (`subtree_min_rows`: horizontal splits sum, vertical splits max). "Two rows at the root" does not give each nested leaf two rows. `interactive_min_rows` is the same recursion over the user's `window.min-height` preference, and applies to drag/keyboard resize ONLY — the layout pass and frame-resize reconciliation use the structural floor, so changing a preference can never invalidate an existing layout. - **Hiding a panel is a durable state transition, not a per-frame effect** (`EditorState::reconcile_panel_layout`): it moves focus out and releases the terminal controller, because the terminal resize path merely returns on zero content without releasing. It runs after attach/resize/display/ close and defensively before input dispatch, terminal sync, and paint. - `FrontendView` gains `panel_capable`, `frame_geometry` (`None` = **unknown**, never the GPU attach request's permanent 24×80 placeholder), and derived `panel_hidden` — each spelled explicitly at every construction site, preserving folding's non-`Default` discipline. - `EditorCore::primary_document_window` is the Q#BP14 projection seam; `display_buffer` is Phase 1 of the display transaction (exact target → side affinity → ordinary reuse, with option-valued height/dedication); the Lua layer owns Phase 2 (activate → hook → reconcile → revalidate → final-focus matrix). - **Optimistic input is gated per WINDOW, not per buffer**: `dispatch_idle_for` returns `false` whenever the acting frontend's active window is a side window. Marking the panel's BUFFER round-trip would be wrong — `round_trip_buffers` is global by `BufferId`, so it would disable optimistic apply for another frontend editing that buffer as its document. - Jump entries are per frontend and carry their origin `WindowId`; a stale **side** origin is SKIPPED, because degrading it to an active-window switch is exactly the duplicate-panel corruption the arc removes. - `pmacs.window.display / display_file / quit / panel / params / set_params / resize / display_target`, plus `builtin/runtime/window.lua` (`window.panel-height`, `window.min-height`, `C-x ^` / `C-x C-^`). Adopters take `display = "current" | "panel"`; **Stage 1 default is `"current"`** and Stage 3 flips it. - The divider is the upper subtree's existing mode-line row — no row added or consumed, `ui.divider` restyles every exposed segment of one boundary, and drag state is `HashMap` so frontends cannot steal each other's gestures. - `open_initial_target` now shares one `resolve_target_buffer` + exact-window install seam with `display_file`, and reasserts into a document window after hooks (a startup hook can now create a panel). - Final gates: 1,817 default + 1,994 CRDT library tests; the new `bottom_panel_stage1_acceptance` 46; kill ring 30; compile 67; M4 121; required GPU 152; initial-target 14 CRDT; all three vterm suites; folding Stage 2 48. All 12 CI checks green at merge. - **Stage 2 (the GPU panel band) is COMPLETE: 2A #177, 2B-1 #184, 2B-2 #187, and 2B-3 (this lane)** — `docs/bottom-panel-stage2-framing.md` rev 6, four framing review rounds, no open framing items; the rev-5 implementation split was explicitly approved 2026-07-27 and rev 6 records PR #184's server-first compatibility and gate correction. It reserved protocol **v21** and shipped as four serial implementation slices: **2A** classified census routing + per-window painter extraction (no wire change, #177), **2B-1** the wire (#184), **2B-2** the daemon projection and epoch machine (#187), then **2B-3** the GPU band, compatible v21 activation, and the negotiated `panel_capable` flip. Production attachment stayed v20 through 2B-2 and negotiates v21 from 2B-3 on. Parent acceptance 37–55 remains authoritative. **Stage 3, the adopter default flip, is the arc's remaining step.** - **The §1.3 census is CLASSIFIED, not uniformly redirected.** Only the Projection class (#1–#12, #21–#22) routes through `primary_document_window`; focus/input (#13–#15, #23), focus chrome and surface-routed (#16–#19), and focus/session (#20) keep their own authorities. Rerouting them breaks remote-op validation and application, `DispatchIdle`, presence, focused search/menu/completion routing, and terminal bell ownership. - **Bottom panel Stage 2B-1 (the reserved v21 wire) LANDED — #184** (merge `6bee09d`, 2026-07-28, two review rounds plus a gate-found follow-up; all 12 checks green on reviewed head `5539b6e`). It adds no producer, no consumer, and no capability: `panel_capable` is still `false` for every semantic session, so nothing about it is user-visible. What it establishes is durable: - **Schema support and production advertisement are separate facts.** `SUPPORTED` is now `6..=21`; the daemon's unsolicited `Hello` still says 20. This is not a hedge — **the handshake is server-first**, so a shipped v20 frontend rejects a `Hello { protocol_version: 21 }` *before* it can send an `AttachRequest`. Bumping the advertised version is therefore an incompatible act on its own, independent of whether any new message is ever sent. A real-daemon acceptance emulates that exact rejection point and then requires the attachment to reach its initial grid. **Stage 2B-3 discharged this without touching the unsolicited `Hello`** — the advertisement is a permanent baseline and the frontend counter-offers; see its bullet below. That acceptance still passes unchanged, which is the point. - **One shared grid validator, split along a stated boundary** (`pmacs-protocol/src/wire_grid.rs`). Shared: checked area, the visible-cell bound (262,144), cell count, cursor bounds, glyph legality, wide-continuation topology, the 8 MiB aggregate glyph-byte budget, and the attachment rejection. Terminal-only: the 512 per-axis PTY caps, title/process metadata, selection spans, and the `at_bottom == (scroll_offset == 0)` coupling. Per-axis caps are a `WireGridLimits` **parameter**, not a constant, because a panel does not inherit them — a 4K surface at a small font is legitimately wider than 512 columns, and the *area* bound is what keeps the encoding inside the transport budget. The attachment rejection is deliberately shared: panels render no attachments either, so classifying it terminal-only would let a panel ship a cell no frontend can paint. - **`PanelFramePayload::Absent` is authoritative, and silence is not.** The receiver retains its last valid frame, so a close *or* a hide must send `Absent` explicitly or a stale band stays on screen indefinitely. Validation is likewise atomic — a bad frame is rejected whole and the previous valid frame is retained. - **Two epochs, answering two different questions.** `panel_epoch` is opaque and monotonic per frontend: stable across ordinary frames of one continuously present window/buffer, and moved on buffer replacement, new side-window creation, and every `Absent` → `Present` transition — which is what stops a stale `PanelPointer` from addressing a reopened panel as if it were the old one (Q#BP16). `geometry_epoch` answers a *frontend* declaration and moves whenever the frontend declares new effective cell geometry, **including a font or scale change that leaves `CellSize` identical** — exactly the case daemon-side value dedup cannot see (Q#BP2S1). - `PanelFrame` carries an explicit `buffer_id` (review round 1) and its `focused` bit is presentation and focus-chrome routing only (Q#BP14b) — the *keys* decision remains `DispatchIdle` (Q#BP14a). - The frontend half is `FrontendEvent::{FrontendCellGeometry, PanelResizeRows, PanelPointer}`, gated in both directions, with each extended enum byte-pinned on its own previous final variant so the v6–v20 encodings are provably unchanged. - **A version bump is not done until every ratchet that pins the old version moves.** The full gate — not review — found that the statusline and Vterm Stage 3 ladders still pinned v20 and rejected v21, in both structural and real-headless-probe form. Grep for the outgoing version across `tests/` before calling a bump complete. - **Bottom panel Stage 2B-2 (daemon projection + epoch machine) LANDED — #187** (one review round of five findings on top of the implementation; 12/12 green; 22/22 mutations bite). What it establishes, beyond the feature: - **A durable transition implemented as a per-frame effect is a bug shape, not a style.** Four of the five review findings were one defect: a renderer-side conditional with a durable twin that disagreed with it. Wire-area exhaustion hid the rendered frame but left panel state live; a stale `panel_epoch` could address a reopened same-buffer panel; `NoMessage` cleared statusline segments it should have retained. The fix that generalizes is `presentable_panel_grid` — **one** private derivation behind both the renderer and `reconcile_panel_layout_core`, because two derivations of one predicate is *how* they drift. When touching panel rendering, ask of every conditional: is there a durable twin, and does it agree? - **Ask what the other frontend kind's equivalent does.** The semantic panel terminal missed the pre-child-drain resize its document sibling had; the repro is a 4×20 panel reporting 3×120. The new `sync_semantic_panel_terminal_layout` is disjoint from that sibling *by construction* — one resolves through `primary_document_window`, the other through `side_window_for` — so the SIGWINCH storm the original extraction prevented cannot recur through the new path. - **A panel may legitimately be wider than a PTY.** `>512` columns are legal on the wire (2B-1's `WireGridLimits` parameter), but `snapshot_for_view` refused the band's content rect and the band went `Absent` with `panel_hidden` false. Clamp the *terminal projection*, not the band: the child takes the columns a PTY can have and the remainder is band background. - **Mutation testing cannot reach behaviour never modelled.** All 16 original mutations passed while five real defects stood; one of them even fired, removing an `Absent` the test asserted. Mutations prove assertions bite the code that exists. They say nothing about the assertion never written. - **One durability hole is accepted deliberately:** epoch exhaustion stays a per-frame `Absent`, flagged rather than hidden, because making it durable needs a new "presentation permanently unavailable" reason in `FrontendView` for a state requiring 2^64 presentations in one session. **Stage 2B-3 did not make it cheap** — the frontend half latches instead, which is a different remedy, so the daemon-side hole stays open as recorded. - **Bottom panel Stage 2B-3 (the GPU band, compatible v21 activation, and the negotiated capability flip) — the arc's Stage 2 is COMPLETE.** This is the slice a user can see: a semantic GPU session now renders a real panel band instead of taking the Stage 1 non-side fallback, which is what closes the journey-steps-7–10 divergence §6 of the Stage 2 framing names. Durable facts: - **A server-first handshake is negotiated from the CLIENT side, not by moving the advertisement.** `ADVERTISED_PROTOCOL_VERSION` is now a permanent compatibility *baseline*; the frontend answers `requested_protocol_version(baseline)` — its own `PROTOCOL_VERSION` when the baseline is the current one, a verbatim echo of anything older — and the daemon records `negotiated_session_version(offer)`. A shipped baseline frontend echoes and gets a baseline session, byte-for-byte as before; a current frontend offers up and gets the current wire. The `Hello` encoding and value never change, which is why the old frontend never sees a version it must reject. **The daemon needed no change to accept the offer** — it already recorded `req.protocol_version` as the negotiated version, so the whole mechanism is one value the frontend chooses plus a documented clamp. - **The window this leaves open, named rather than hidden:** a daemon whose own `PROTOCOL_VERSION` equals the baseline rejects an offer above its supported range. Compatibility can be preserved for old *frontends* or old *daemons* — a single `AttachRequest` cannot mean both "I want 21" and "≤ 20" — and the frontend direction is the one that matters, because the daemon is what a user leaves running. It closes on the next daemon restart and surfaces as an explicit `GoodbyeReason::VersionMismatch` naming both versions. - **`server_protocol_version` split into two facts on the GPU client**: `session_protocol_version` (what the session speaks — every wire gate keys on this) and `baseline_protocol_version` (what `Hello` said). They now DIFFER in the normal case, and that difference *is* the compatibility property, so both headless probe reports emit both and the two ratchets that read them assert both directions. Asserting only the session version would pass if the baseline had been bumped too, which is the exact incompatible change the mechanism avoids. - **The GPU document bottom is three boundaries and each call site was classified individually** — 20 production sites (8 status-owned, 12 document-owned), 1 definition, 8 test sites, 29 matches, arithmetic stated. `geometry_capacity_bottom` reserves the divider *while the panel is absent* (that asymmetry is what breaks the first-open cycle) while `document_text_bottom` costs the document nothing until a `Present` frame paints. - **Moving a boundary is not always sufficient.** `edge_scroll_direction` has no upper bound, so a pixel *inside* the band still read as "further down the document" and armed the document's auto-scroll — the exact named symptom, surviving a correct reclassification. Any consumer that treats "past the bottom" as unbounded needs the band as an explicit exclusion, not just a moved boundary. - **Three of the first-pass assertions were VACUOUS, and the mutation runs are what found them.** (a) The contrast assertion compared `status_band_top` before and after — a *fixed point* — so the blanket rewrite it exists to prevent moved both readings together and passed; it is now anchored to an independent formula. (b) The criterion-46 pixel test passed with the band painting *nothing*, because installing a panel reshapes the document and that produced the whole diff; it now counts differing pixels in the divider and cell rows. (c) The probe-versus-document-advance fixture compared two ASCII documents, which in a monospace family have identical advances. - **"No panel frame reaches a v20 session" is defence in depth, not the placement gate.** The producer's peer flag and the write-loop filter both suppress `PanelFrame` below the panel version independently of `panel_capable`, so that assertion passes with the capability gate removed entirely. The load-bearing claim is *placement*: the adopter's buffer must land in the pre-panel session's own document window, because a side window it cannot render is simply invisible. - `PanelBand::presented()` is the ONE frontend-side derivation of "is a band on screen" — retained valid frame, matching `geometry_epoch`, latch clear — behind the band inset, the painter, the hit-tester, and the drag. A latched frontend also stops absorbing payloads, so `presented()` is not the only thing between a disowned declaration and a painted band. - Panel columns come from the **stable normal-face probe**, never `mono_advance`'s document-glyph fallback, and `panel_cell_capacity` carries the daemon's **virtual status row** (`frontend_area_rows` is `total.rows - 1`) with **no per-axis cap**, because a panel may legitimately be wider than a PTY. - `PANEL_MIN_VERSION` moved into `pmacs-protocol` so the GPU frontend aliases one definition instead of restating 21. - **Stage 3 (the adopter default flip) is the arc's last step**, and it is the only thing between today's state and omitting `display` resolving to the panel policy. - **dired Stage 2 framing LANDED (document only) — #171** (`docs/dired-stage2-framing.md`, revision 9; seven review rounds). **Approved as a framing; no runtime code and no implementation started.** Load-bearing decisions a reader must not re-derive: - **Reconciliation is order-independent, deliberately.** Reply order is *not* execution order — `AsyncRuntime::tick` drains the bus with `try_recv`, so a worker can finish first and be descheduled before sending. An ordering token was rejected rather than built: no static rule rescues the hazard anyway (rename `dir`→`newdir` racing delete `dir/child.txt` needs opposite orders depending on which ran first), and no production path can produce it. The trigger to revisit is named: the first production caller that fire-and-forgets two interdependent mutations. - **A refused mid-edit kill is already destructive.** `kill_buffer` clears round-trip state and moves windows *before* `BufferRegistry::remove` can return `ConcurrentEdit`, so `editing_in_progress` must be preflighted rather than relied on to refuse cleanly. - **Path-backed buffer names are not full paths.** `get_or_load_buffer` takes the name from the path *as given* and normalizes only the stored path, so a relative open is named `foo.rs`. Rename provenance is path-*equivalence*, not equality. - **URI-keyed stores have uncorrelated writers.** `textDocument/publishDiagnostics` is absorbed unconditionally, and `mark_document_stale` takes no `LspServerId` at all while creating URI keys across three stores. A route purge keyed on request responses cannot cover either. - **Resource-op delete-guard implementation LANDED — #190**, atop the framing #186 below. The pre-filesystem refusal now exists: a synchronous `apply_resource_op` delete that would destroy unsaved work is refused before the filesystem is touched, rather than after. - **A refusal that no production path can reach passes every direct-call test.** The guard is asserted through the outermost user-reachable seam and falsified by revert, not by calling the check directly. This is the general rule now recorded in §5. - **Delete refusals must be visible.** Review round 2 found them silent — the operation declined and the user learned nothing. Reporting goes through `pmacs.editor.set_status`; `pmacs.error` is still a channel defined only by a test stub (§5). - **A URI-keyed store is not one store.** Purging a route keyed on request responses covers neither `mark_document_stale` (which takes no `LspServerId` while creating URI keys across three stores) nor `DiagnosticView`, whose URI is fixed at construction. - **dired Stage 2a LANDED — #196** (`docs/dired-stage2-framing.md` rev 9, §5/§6/§10 — the substrate transaction only, **no dired surface**). Rename and delete reconciliation across the path owners a rename actually crosses. - **A rename is a transaction across five owners**, and this is the fact that forced the 2a/2b split: the buffer path, the buffer name, the URI-keyed LSP stores plus `DiagnosticView`, dired's pathless handles, and a captured Lua local that no transaction can reach. Stage 2b owns everything needing new Rust primitives. - **New LSP resource subscribers must not swallow reconciliation failures**, and `forget_uri` must not leave purged requests live in `LspClient.pending` — both were review findings, both now pinned. - **Generated-buffer immutability Stage 1 LANDED — #191**, adopting the contract framed in #188. `dired.lua`'s `paint` and `listview.lua`'s `render` write through `pmacs.buffer.set_generated_contents`; zero `bypass_intercept` writes remain in either file. - **Why these two families first, and it is not the cheap half.** `compile.lua` and `builtin/commands/default.lua` rebind all seven undo chords to a no-op; `dired.lua` and `listview.lua` rebind **nothing**, so a bare `C-/` emptied a listing and a panel. Stage 1 closes the only two families reachable without `M-x`. - **The framing owns the acceptance contract; the implementation adopts it.** Review round 5 found #191 had locally restated Stage 1 criteria while #188 still carried the originals. Where an implementation finds a criterion impossible, the framing is revised and re-approved first — it is not narrowed in place. - **Stage 2 still owes everything with new Rust in it:** `Buffer::apply_generated_edit`, the `{ generated = true }` option, Q#GB10's path-backed refusal, Q#GB15's `identity_protected`, Q#GB5's `ensure_slot` lock, and the remaining 13 write sites. - **Generated-buffer immutability framing LANDED — #188** (`docs/generated-buffer-immutability-framing.md`, revision 7; six review rounds, thirty-two findings). Revision 7 is the governing contract for the whole arc. - **Resource-op delete guard framing LANDED (document only) — #186** (`docs/resource-op-delete-guard-framing.md`, revision 5; five review rounds). **Approved as a framing; no runtime code.** It owns the urgent **pre-filesystem refusal** for synchronous `apply_resource_op` — which on `main` today destroys unsaved work — while #171 owns full post-delete lifecycle reconciliation. Carried facts: - The sequence is `stat/no-op -> enumerate and validate -> mutate filesystem -> reconcile`. Validation inspects without removing, so a failed deletion leaves buffers intact and `on_removed` still observes the path already gone. - **`EditorCore::find_buffer_for_path` is the wrong lookup** — it delegates to first-match-only `find_by_path`, and `pmacs.buffer.from_file` creates path-bound buffers with no dedup, so a clean first match can hide a modified second. - **LSP does not promise batch atomicity, and pmacs advertises no `workspace.workspaceEdit` capability at all** — no `documentChanges`, no `resourceOperations`, no `failureHandling`. Recovery is the client's declared choice, and there is no spec default for a client that declares none. Say only that observed pmacs behaviour *resembles* abort-style application. - **`pmacs.fs.remove` has no dirty check of its own** and neither lane adds one. After both land the guards sit one layer above it. Latent — zero production callers — but "both lanes guard deletion" reads as the primitive being guarded, and it is not. - **GPU initial target LANDED — #148** (`docs/gpu-initial-target-framing.md` rev 3; merge `0dd16a5`; two review rounds). `pmacs --gpu [--socket NAME|PATH] FILE` transports exact Unix path bytes plus launcher cwd to the managed GPU client. Protocol v20 adds a semantic-session `SessionBootstrapRequest` after `AttachRequest` and an appended `InitialTargetResult` readiness barrier; v6–v19 wire encodings stay pinned. The daemon resolves the path lexically, deduplicates or loads/creates it in the authenticated frontend's view, runs the established load/switch hooks, upgrades the buffer for CRDT, and publishes every target-side CRDT upgrade to existing grid replicas before readiness. Semantic replicas receive a publication only when displaying that buffer, so a second target launch cannot switch an existing GPU window; one dead peer cannot fail the new session. Failed bootstrap writes a bounded result, shuts down the socket, removes provisional state, and restores the ambient active frontend. Any stale event from an uninstalled session is dropped before state access. Existing no-target managed launch, direct attach, TUI, and legacy protocol behavior remain intact. Folding Stage 2 integration: fold projection at attach is selected from the same negotiated `semantic_render` bit the target bootstrap uses (grid collapses, semantic/GPU stays source-line pending Folding Stage 3). Final gates: 1,815 default + 1,992 CRDT library tests; target + invocation gates 14/14 CRDT each; Folding Stage 2 48 CRDT; M4 121; required GPU 152; Vterm Stage 3 5 default + 7 CRDT; isolated-config workspace sweep 3,334 across 88 suites; two concurrent real Wayland/Vulkan GPU windows stayed on distinct target buffers after the second attach. All 12 CI checks passed. - **Folding Stage 1 (headless fold engine) LANDED — #142** (`docs/folding-framing.md` rev 5; merge `c49a8c7`; three review rounds, round 3 clean). Arc 6's engine — instance-side and headless; **no frontend renders a collapse yet** (that is Stage 2). No protocol bump. - `src/fold.rs`: a per-buffer `FoldStore` of byte ranges attached as a translating/dropping `View` (the `BufferStyleSpanTranslator` pattern — it translates strictly-inside edits and DROPS boundary-crossers, provenance-blind); `FoldRegistry`/`SharedFoldRegistry` = `Rc>, ViewId}>>>` (the SyntaxRegistry per-buffer model), held on both `EditorCore` (`src/editor_core.rs:223`) and `EditorState` (`src/editor.rs:110`). Containment is **start-exclusive, end-inclusive `(start, end]`**; the stored range is `[end of head line, end of last hidden line]` (NOT the `ByteRange` struct doc's `[start,end)`). - Structural source: nearest enclosing block-like node ≥2 source lines → resolve introducer↔body → **derived head line** (the line immediately above the first hidden line, so wrapped signatures / `where` clauses stay visible) → **closer-aware tail** (a closing-delimiter line stays visible, e.g. `} else {`). Stale/absent parse tree refuses. - The six `EditorCore` edit primitives call `unfold_before_point_edit` first (command-path pre-edit unfold, keyed on the active frontend's point). Interactive Lua-command unfold (yank/query-replace/comment) is a Stage 2 obligation; CRDT-origin unfold is Stage 3. - `src/lua_bindings/fold.rs` (`install_fold`): `pmacs.fold.*` data API (explicit buffer, no ambient resolution, matching #127) + interactive commands on the **Emacs hideshow `C-c @` prefix set**; `builtin/runtime/fold.lua`. - `src/semantic_render.rs`: `fold_state_msg` PRODUCES `FoldState` (semantic/GPU sessions) — authoritative-empty, diff-suppressed, per-session baseline reset on `BufferSnapshot` (the #120 stale-mirror trap class; the GPU fold-mirror clear-on-snapshot is a named Stage 3 obligation). - Durable lesson (round 2): after wiring a cleanup into a production hook, PIN IT THROUGH THE REAL PATH — a direct-call unit test misses the wiring (falsify by revert). - **Stage 2 (grid/daemon collapse) LANDED — #149** (merge `6ed4fe9`; five review rounds; `docs/folding-stage2-framing.md` rev 4). Its load-bearing reframe: the TUI had **no non-identity source-line↔display-row map** (`view_top + row` was baked into ~13 sites), so Stage 2's spine is `src/fold_view.rs`'s `VisibleLineMap` — derived from the fold store plus a window's line offsets, never stored — that the render loop, gutter, diagnostics, caret, selection, peer presence, viewport/scroll/motion, and the mode-line indicator all route through, plus the interactive-Lua unfold widening. Threaded as `Option<&'a VisibleLineMap>` on a lifetime-bearing `Viewport<'a>` that stays `Copy`. Design points the review rounds forced, each a trap for Stage 3: - the map's unit is a **merged hidden component** (overlapping *or adjacent* intervals unioned, keeping the earliest visible head), not a fold — folds may cross, and an inner/later fold's own head can be hidden; - instances are **per rendered window** and **per command/event operation**, never per frame; a command's map follows the operation's TARGET window (a wheel event names a pane without activating it); - fold projection is **per-frontend** (`FrontendView.fold_projection`, set at attach from the negotiated `semantic_render` bit) — shared `EditorCore` motion would otherwise make a simultaneous unfolded GPU session's cursor skip lines it still displays; - a hidden cursor normalizes by **position**, not row, and `set_view_top` clamps in the setter rather than being repaired at render time; - the interactive-Lua unfold keys on the **post-intercept** edit site — a managed buffer intercept may legally relocate the op. No protocol bump. **Stage 3 (GPU) is next and has no framing yet**; its named obligations are GPU collapse at TUI parity, caret/hit-test fold-awareness, the `BufferSnapshot` **fold-mirror clear** (parent R2-4 — the #120 trap class), CRDT-origin / GPU-optimistic interactive unfold (parent R2-3), and flipping `FrontendView.fold_projection` to `true` for semantic frontends. - **One-command GPU invocation LANDED — #141** (`docs/gpu-invocation-framing.md` rev 6; merge `63fbc66`; two implementation reviews). The additive public path is `pmacs --gpu [--socket NAME|PATH]`; bare `pmacs [FILE]` remains the TUI. Root owns the CRDT gate, socket resolution, sibling-regular-file GPU discovery/PATH fallback, and GPU outcome. The separate `pmacs-gpu` binary owns connect-or-start, a five-second / 50-ms retry window, pre-winit event buffering, daemon process-group/stdin/stdout/stderr isolation, and named child reaping with explicit ownership handoff. Direct `pmacs-gpu --attach RAW_PATH` remains strict, is documented as advanced, and never auto-starts. No protocol change. The initial macOS/LuaJIT CI run exceeded an unrelated outline performance threshold (147 ms / 100 ms); the complete failed-job rerun passed all twelve checks before merge. - **Config registry LANDED — #127** (`docs/config-registry-framing.md` rev 3; merge `2e37c04`; two review rounds). `pmacs.config` is the typed, introspectable options registry the backlog ranked first, and it closes the "config-registry-blocked" deferrals below. It was built as a PARALLEL LANE alongside vterm in a sibling worktree; the files were assigned per-lane up front and the rebase had zero conflicts. - **Third registry** beside `CommandRegistry`/`HookRegistry` (`src/config_registry.rs`), same R42/R50/duplicate-rejection/ `SourceLocation` vocabulary; Lua surface in `src/lua_bindings/config.rs`. **No protocol change (still v18) and ZERO changes to `src/editor.rs`.** - **An override is ALWAYS stored**, even when equal to the value it shadows; only `value_epoch` and listener dispatch key on effective change. The "equal-value set is a no-op" reading silently voids a buffer-local pin: nothing is stored, and a later global `set` flips the very buffer the user pinned. - **Two scopes: global and buffer-local.** `get(name, buf)` resolves local → global → default; **`get(name)` resolves the GLOBAL CHAIN ONLY** and never consults an ambient buffer. Per-language and per-project are *patterns* (a hook calling `set_local`), not scopes the registry knows about. Mode keymaps now resolve through #129, but `pmacs.config` deliberately remains global + buffer-local. - Buffer-locals live in a registry side table purged at `after_buffer_removed`, beside the keymap purge. - Listeners: commit → snapshot → **drop the borrow** → re-enter Lua; a raising listener is logged without blocking the rest or rolling back; a depth bound turns a cycle into a pointed error. **Explicit dispose only** — there is no `MetaMethod::Gc` anywhere in the codebase, and GC timing differs between the two Lua backends. - `StartupOnly` freezes off the existing `InitCompleteFlag` at write time (which is why no `editor.rs` call was needed). In `--lib` builds `set_init_complete` never runs, so a post-freeze test must flip the flag explicitly or it passes vacuously. - Adopters own their own `define`, so `SourceLocation` names the owning module: `editing.auto-pair` (pair.lua, read against the typed edit's SOURCE buffer), `editing.trim-on-save` (editops.lua, read against the buffer being saved), `autosave.interval-ms` (autosave.lua, re-read per tick). **The migration wrappers keep their legacy coercion** — the registry is strict, the legacy setters stay lenient (`trim_on_save("yes")`, `interval_ms(1500.7)`). - `M-x describe-setting` renders into `*help*`. - **Mode system wiring LANDED — #129** (`docs/mode-system-wiring-framing.md`; merge `b4b925d`; one review round). The existing mode-keymap substrate is now live without a protocol change. - `Buffer.major_mode: Option` owns the single major mode. The detected language name initializes it once on `buffer.after-load`, before grammar gating, so server-only languages work; switches never rewrite it. Explicit overrides and clears survive switches. A future reload that fires after-load re-detects, and explicit mode state is not session-persisted. - Dispatch borrows the zero-or-one mode through `Option<&str>::as_slice()` and `&[&str]`: no hot-path mode allocation. Resolution remains buffer-local → mode → global, and registry/keymap borrows end before Lua command invocation. - Lua surfaces: `pmacs.buffer.major_mode` / `set_major_mode` and `pmacs.editor.active_modes`. `pmacs.describe.key`, `pmacs.help.show_key`, and followed percent-encoded `@mode:` links use the same effective context; `pmacs.keymap.lookup` remains raw-global. - The built-in `mode` statusline provider reads `ctx.buffer`, so passive splits render their own mode. Real-daemon acceptance covers all ten framing criteria across both Lua backends and Linux/macOS CI. - **Modeline language detection LANDED — #132** (`docs/modeline-detection-framing.md` rev 2; merge `1dd47fc`). Fresh loads scan bounded Emacs `-*- mode: ... -*-` and Vim/Vi `ft=` / `filetype=` modelines without evaluating file content, normalize common editor aliases, and give explicit modelines precedence over inferred language. - `builtin/runtime/syntax.lua` owns one per-buffer fresh-load decision: modeline → bundled grammar extension → LSP filetype extension → exact filename → shebang. Syntax, initial major mode, pairing, comments, and LSP all reuse that pin; LSP retains its independent backing-path guard. - Editing a modeline or shebang does not switch an attached parser or make language-aware consumers diverge. Close/reopen re-evaluates changed file metadata. Explicit post-load major-mode overrides remain independent. - Bounded valid unknown names remain passive major modes without starting an unavailable parser or server. All thirteen framing criteria are covered on LuaJIT and Lua 5.4. No Rust or protocol surface changed; protocol stays v18. - **Syntax-highlight / language-detection side-quest (#114–#118) LANDED** — a one-shot arc built in sibling worktrees off main while the user's themes lane (`theme-faces`) ran concurrently in the shared checkout. All merged. What shipped: - **Grammars** (`crate::syntax::BUILTIN_LANGUAGES`): every LSP-configured language now has one — cuda, bash, dockerfile (via the ABI-current `tree-sitter-containerfile`, NOT the dead `tree-sitter-dockerfile` which pins `tree-sitter ^0.20`), make, cmake, python, go, javascript (+jsx), typescript (+tsx), toml, zig. - **Detection chain and pin** (`builtin/runtime/syntax.lua`): modeline → grammar extension → LSP filetype map → filename → shebang. User-extensible Lua surfaces include `pmacs.parse.modeline_aliases`, `.shebangs`, `.filenames`, `language_from_modeline`, `language_from_shebang`, `language_from_filename`, and the pinned `buffer_language`. `builtin/runtime/lsp.lua` delegates to that shared decision after enforcing its backing-path requirement. Grammar name MUST equal the `pmacs.lsp.config.` key. A buffer keeps its pinned language across edits/switches; close/reopen performs a fresh bounded inference. - **LSP configs added**: dockerfile (`docker-langserver --stdio`), cmake (`cmake-language-server`, config via `init_options.buildDirectory="build"` — it does NOT pull `workspace/configuration`). Make has no server. - **Substrate**: `LanguageEntry.highlights_query` and `.locals_query` are `&[&'static str]` fragments joined base-first (cuda over c/cpp; ts over js/jsx). Since locals-query processing #134, settle compiles the grammar's `LOCALS_QUERY`, resolves Tree-sitter's scope/definition/value/ reference conventions into sorted `LocalFacts`, and stores them beside each layer's tree/query. Work runs once per fresh bundle and only when the highlight query asks about `local`; viewport rendering remains bounded. Both TUI and semantic/GPU producers evaluate `#is?`/`#is-not? local` through the shared capture walk. Non-shadowed JS/TS builtins are restored; shadowed definitions/references keep ordinary variable styling. - **Multi-language injections (#122) LANDED** — the direct continuation of the #114–#118 highlight arc; four review rounds, framing `docs/multi-language-injections-framing.md` (Q#IJ1–IJ11). A buffer can now hold more than one language: `ParseTreeBundle` holds `Vec` (root + injected children, depth-ascending, installed atomically so the existing `StyleGate` + highlight-cache Arc gates still work). The parse worker builds child trees off the static `BUILTIN_LANGUAGES` table (lazy load preserved) via `set_included_ranges` — child node offsets are ABSOLUTE, so injected spans are buffer-coordinate-native; settle resolves each layer's highlight query (`SyntaxRegistry::resolve_layer_queries`). First consumers: markdown fenced code + `markdown_inline` (retires the M9.7 block-only floor). New substrate: `LanguageEntry.injections_query`; `default_injection_aliases` + `SyntaxRegistry::injection_alias_snapshot` (case-folded fence names, Lua-extensible via `pmacs.parse.injection_aliases`, snapshotted into `ParseRequest` so the worker never touches the `Rc` registry or Lua); `ParseTreeBundle.injection_capped` (the 4096-layer backstop, surfaced once/buffer via `pmacs.error` at settle); `compute_highlight_spans_for(query, tree, source, local_facts, range)` (per-layer); the wire `flatten_layer_spans` event-sweep → DISJOINT effective spans (deeper / later-sibling / narrower wins, keyed by `(layer_index, capture_order)`); GPU `spans_from_segments` + `source_color_at` fold. Two findings to keep: injection ranges exclude only NAMED children (anonymous tokens ARE the injected text — excluding them shreds a block `inline` node; matches tree-sitter-md's own splitter), and the wire flattener runs over the WHOLE buffer via the file-style summary, so it must be an event sweep, not O(spans²). - **JSON + YAML grammars and language servers (#123) LANDED** — bundled ABI-current `tree-sitter-json` / `tree-sitter-yaml` cover `.json`, `.yaml`, and `.yml`; the existing injection engine now highlights YAML frontmatter and JSON/YAML fences. Default external LSP configs are the pinned `vscode-json-language-server` provider and `yaml-language-server`; configured settings are pushed after `initialized`, which also supports push-model servers. The fake-server delivery proof and PATH-gated live JSON/YAML provider smokes cover the configuration contract. `.jsonc` / `.json5` remain a deliberate follow-up because the JSON grammar is strict. - **Compile-mode (Arc 5 stage 1, #113) LANDED** (2026-07-14, 7 rounds; framing `docs/compile-mode-framing.md` rev 13). `compile.run` streams `/bin/sh -c "exec 2>&1; "` into an intercept-read-only `*compilation*` buffer via a Lua ANSI parser; once-per-newline error rules; unified `error.next`/`error.previous` (M-g n/p, `` C-x ` ``, M-!). Substrate other code can use: `ProcessSpec.stdin/group` (group lifecycle: reap ledger, in-drain enforcement, cancellable poll readers), `buf:revision()`, jump_back fires `buffer.after-switch`, `pmacs.errors.claim`, `AnsiParser::finish()` (observable reset), and the style-overlay stack: buffer-attached `BufferStyleSpanTranslator` (once-per-edit, fragment-preserving), render-only window overlays with identity-deduped `Window::ensure_overlay` + `clone_for_split`, idempotent atomic `handle:dispose()`. - **Editing-conveniences pack (editops, #111) landed** (framing `docs/editing-conveniences-framing.md` rev 6). goto-line, case ops, transpose, zap-to-char, line move/duplicate/join, region sort/reverse/dedupe, delete-trailing-whitespace + opt-in `pmacs.editops.trim_on_save`. Substrate: `pmacs.killring.kill_range` / `break_chain([fid])` / `arm_kill_prompt`+`commit_kill_prompt` (marker lifecycle), and the origin-guard pattern for chain-sensitive minibuffer commands. - **Auto-pairing (#110) landed — Arc 2 COMPLETE** (framing `docs/auto-pairing-framing.md` rev 6). `BUILTIN_PAIR_CHARS` in pmacs-protocol leave both frontends' optimistic classifiers; `builtin/runtime/pair.lua` loads BEFORE lsp.lua (first-didChange ordering contract); one-shot typed-edit provenance via `pmacs.editor.take_typed_edit()` (buffer-revision postcondition, Q#AP9). Substrate: `buf:path()`, `pmacs.lsp.buffer_language(buf)`, `PMACS_FAKE_LSP_CHANGE_SINK`, `TestDaemon::spawn_with_config`. - **Themes (Arc 4) stages 1–3 LANDED; Arc 4 COMPLETE ON `main`.** - Stage 1 (#120, `docs/theme-faces-framing.md` rev 9): named UI faces as reserved `ui`/`ui.*` theme entries; transactional split syntax/face epochs; protocol-v16 `ThemeFacts`; snapshot/baseline symmetry; store-sourced diagnostic-count freeze. - Stage 2 (#124, `docs/gpu-set-font-framing.md` rev 5): `pmacs.gpu.set_font` and authoritative protocol-v17 `FontFacts`; frontend-local family resolution, live font reload/reflow, and visual-run caret geometry. - Stage 3 (#125, `statusline-segments`, `docs/statusline-segments-framing.md` rev 3): composable strict `pmacs.statusline` providers; borrow-released per-window evaluation with failure latches; legacy-preserving TUI composition; a pure built-in LSP provider; dynamic modeline faces; protocol-v18 `StatuslineSegments`; authoritative-empty/snapshot symmetry; and atomic GPU validation, face resolution, shaping, clipping, and cache invalidation. Acceptance 1-27 is implemented. Final gates: Clippy clean; 1,619 default + 1,793 CRDT library tests; 7 default + 8 CRDT feature acceptance; 114 M4; 109 required GPU; one-invocation workspace sweep 2,718 passed across 78 suites (19 ignored, `basedpyright` filtered); `git diff --check` clean. Stage 3 landed as #125 and completed Arc 4 on `main`. - **Vterm Stage 1 terminal core LANDED ON `main` — #126** (`docs/vterm-framing.md` rev 5; merge `643d1e1`). - Implementation commits: `bbc1f33` (Stage 1), `962944b` (Darwin signal normalization), first-review fixes `f0a235f`, `28f2e6c`, `bf972a7`, and second-review hardening `9797ada`; reviewed feature head `fc4e0ce` merged through PR #126, . - `AnsiParserProfile::{LineOriented, FullScreen}` preserves compile/REPL behavior while terminal PTYs emit the full cursor/mode/device operation set. `src/terminal/{screen,input,session}.rs` owns the state machine, encoders, and lifecycle registry. - Public session seam: owned strict `TerminalSpec`; owned `TerminalSnapshot`; `TerminalProcessState`; and `SharedTerminalManager = Rc>` with `open/is_terminal/process_id/snapshot/tick/send/resize/terminate/prune/ shutdown`. Stage 1 snapshots are context-free; Stage 2 adds per-view state without a second screen. - `EditorState` tick order is supervisor → terminal-owned PID drain/prune → `process.after-tick`. Terminal IDs are not exposed through `pmacs.process`; ordinary Lua/LSP/MCP ownership is unchanged. Terminal identity buffers are pathless, clean, empty, round-trip, and guarded read-only at every rope/CRDT/history mutation boundary. - Acceptance 1–14 is mapped in the framing. The real PTY bite splits ESC/CSI writes, observes alternate-screen cursor addressing, blocks and resumes through raw `send`, restores the main screen, and pins final output before exact PID/outcome annotation. One-row annotation visibility, TERM-ignoring shutdown, spawn rollback, buffer-kill prune, and immutable empty CRDT bootstrap are pinned. - Review round 1 added typed IND/NEL/RI with margin-correct screen behavior, defaults absent `TERM` to `xterm-256color`, makes shutdown liveness acceptance portable with `kill(pid, 0)`, and preserves custom tab stops on resize. Review round 2 rejects C0/C1 controls before they enter screen cells, preserves the released button code in SGR mouse reports, removes dead screen paths, and clears stale round-trip state during prune. Stage 2 now uniquifies default terminal buffer names transactionally. - Exact CUU/CUD and out-of-range DECSTBM clamping, combining across controls, xterm alternate-screen details, legacy non-SGR mouse, printable ASCII and CSI-dispatch allocation fast paths, and scrollback-cap naming are explicit post-arc deferrals in the framing. - Final from-start rerun after review round 2: Clippy clean; 1,661 default + 1,837 CRDT library tests (3 ignored each); 9 default + 10 CRDT vterm acceptance; M4 114 passed (3 ignored, 1 filtered); required GPU 109; workspace 2,769 passed across 79 suites (19 ignored, 1 filtered); diff check clean. `scripts/bite HEAD^ src/terminal/screen.rs --test vterm_stage1_acceptance terminal_cells_reject_child_control_characters` is a clean behavioral bite. The parser dispatch has its independent clean behavioral bite; the original `main`/crate-root bite remains explicitly weaker compile-time API evidence. - **Stage 3 GPU/protocol LANDED ON `main` — #135** (merge `cac4961`; `docs/vterm-framing.md` Revision 9, criteria 28–37). Protocol **v19**: `InstanceMessage::TerminalFrame` (discriminant 26, daemon-gated) plus `FrontendEvent::TerminalResize` (11) and `TerminalPointer` (12), both frontend-gated — the first bump gating in BOTH directions. `SUPPORTED=[6..=19]`. - `pmacs-protocol/src/terminal.rs` now owns the shared terminal bounds, `TerminalProcessState`, `TerminalSelectionSpan`, and the single structural policy `TerminalFrame::validate`; `src/terminal/*` re-exports them so no duplicate type exists. `unicode-width` is a workspace dependency so the screen and the validator measure glyph columns identically. `MAX_TERMINAL_FRAME_GLYPH_BYTES = 8 MiB` bounds the payload instead of widening the transport cap; the measured maximum legal frame encodes to 13,437,863 bytes under the unchanged 16 MiB `MAX_FRAME_BYTES`. Over-bound snapshots are rejected, never truncated or silently chunked. - **The `Viewport` gate keys on the AUTHENTICATED SOURCE'S ACTIVE BUFFER, not the buffer the message names.** `Viewport` also aligns the window to the buffer it declares, so a stale document viewport in flight when a command opens a terminal drags the frontend back off it - the terminal then never paints, with no error anywhere. The weaker "is the declared buffer a terminal" reading looks right and fails exactly this way. - Suppression compares the COMPLETE ordered payload, never `screen_generation`: scroll, selection, viewport, and process state all change without advancing it. - GPU: `pmacs-gpu/src/terminal.rs` is a pure cell-space paint planner (testable without a GPU); the renderer builds one shaped buffer per text run so a wide/cluster advance can never choose the next column's origin. `pmacs-gpu --headless-probe` drives the real attach client without winit (`attach::connect_with_sink`), which is how criterion 37 gets one real daemon + real PTY + real wgpu path. - #135 integrated canonical `main` after #137 landed. The one code conflict joined `TAB_STOP_COLUMNS` with the terminal imports in `pmacs-gpu/src/main.rs`; terminal geometry remains fixed-cell and never consumes the document tab-stop projection. - Final post-integration gates: strict Clippy; 1,768 default + 1,944 CRDT library tests; Vterm Stages 1/2/3 at 9/10, 4/4, and 5/7 default/CRDT; statusline 7/8; tab-width 2/2; M4 121; required GPU 139; workspace 2,946 passed across 84 suites; formatting and diff check clean. The first macOS/LuaJIT CI run timed out waiting for `VTERM_ALT_READY` in the Stage 2 real-TUI smoke; the complete failed-job rerun passed all 12 checks. - **Stage 2 TUI LANDED ON `main` — #130** (merge `86fc1bc`; `docs/vterm-framing.md` Revision 7, criteria 15–27). `TerminalViewKey` keys per-frontend/window projection state over one shared process/screen; logical row anchors retain scroll/selection through reflow. One authenticated frontend controls at most one session, with atomic replacement and release on focus/switch/kill/detach. - The strict `pmacs.terminal` Lua surface owns open/state/view/send/terminate and context-implicit scroll/copy commands; the latter error unless the invoking frontend's active window is a terminal. Fixed `C-c` is the per-frontend terminal escape: only its next key reaches terminal-local editor bindings, while unescaped bound keys pass through to the child. `C-c C-c` sends one literal interrupt. Copy drains through the acting frontend's clipboard path; active BELs drain once locally and per daemon frontend, while historical/passive bells are baseline-suppressed. - TUI composition paints owned terminal cells/styles only inside each window's content rectangle, suppresses document overlays, and keeps sibling splits independent. Daemon key/mouse/paste/focus/resize/detach routing uses the authenticated connection source rather than client-claimed IDs. `builtin/runtime/terminal.lua` provides the terminal command, view commands, and pure `ui.modeline.terminal` process/scroll segment. - `tests/vterm_stage2_acceptance.rs` maps Lua transactionality, shared-view isolation, clipboard/modeline behavior, and a hermetic real `/bin/sh` TUI PTY smoke. Stage 2 changed no wire schema or GPU renderer; protocol remained v18 until Stage 3. - PR #130 review round 1 (`8702791`) aligned dispatch with the approved escape-prefix contract, closed the non-terminal Lua error path, made controller replacement atomic, retained zero-area view anchors, removed duplicate detach work, and replaced per-view deep scrollback clones with borrowed live/published row projections. Focused child-input coverage pins both unescaped bound-key passthrough and `C-c C-c`. - PR #130 review round 2 (`b9a7e40`) clamps anchors into the first surviving cell when eviction cuts through a wrapped logical line, prevents ambient `active_frontend` from minting interactive Lua authority, names malformed explicit-context fields, restores dispatcher rationale, and removes owned cell snapshots from terminal mouse routing. The framing now records the transient v18 semantic-controller boundary and bracketed-paste injection deferral. - Current-main integration (`3f0252f`) preserved per-frontend terminal dispatch while applying the landed mode-scoped keymap, and exposed the `mode`, `terminal`, and `lsp` statusline providers together. PR #130 merged at `86fc1bc`. - Final integrated gate: `cargo fmt --check`; strict workspace Clippy; 1,753 default + 1,929 CRDT library tests (3 ignored each); mode-system acceptance 1 default + 1 CRDT; Stage 1 acceptance 9 default + 10 CRDT; Stage 2 acceptance 4 default + 4 CRDT; statusline acceptance 7 default + 8 CRDT; M4 114 passed (3 ignored, 1 filtered); required GPU 109; workspace 2,882 passed across 82 suites (19 ignored, 1 filtered); `git diff --check` clean. - **Tab-width rendering parity LANDED — #137** (merge `2625ec7`; `docs/tab-width-parity-framing.md` rev 2). Source tabs remain one byte while every buffer renderer follows the shared fixed `pmacs_protocol::TAB_STOP_COLUMNS = 8`. - `src/display_width.rs` owns allocation-free Unicode/tab-aware byte-to-column accounting for plain text, syntax, diagnostics, completion anchors, buffer-style overlays, and search washes. - The GPU rich-chunk projection expands source/adornment tabs before cosmic-text shaping and retains first-class source-tab provenance. Carets, hits, selections, peer washes, and diagnostic geometry share the same source/projected boundary rules, including a soft wrap inside one expanded tab. - GPU minimap widths use the same tab/Unicode rule and refresh in the accepted text-edit transaction. No config, wire shape, negotiation, or protocol version changed. Local gates: 1,763 default + 1,939 CRDT + 1,763 Lua 5.4 library tests; 2 focused acceptance; M4 121; required GPU 119; workspace 2,911 across 83 suites; strict Clippy and diff check clean. - This closes the standing "**tab width is a rendering-parity bug, NOT a config gap**" deferral in §5: one shared constant now drives every renderer. Terminal cells are deliberately OUTSIDE it — a terminal's columns come from the child, so `pmacs-gpu`'s terminal geometry uses the monospace advance and never `TAB_STOP_COLUMNS`. - **PARKED: kill-ring browser + persistence.** Revision 2 framing is preserved on branch `kill-ring-browser`, but its `0efb5cd` scout is stale and must be repeated before implementation. No PR or implementation is active. - Roadmap: `docs/roadmap-2026-07.md` (ranked arcs). Position: - **Arc 1 (LSP utility surface) COMPLETE** — completion popup (#92/#93), panels/references/outline/hover (#94–#96), plus hardening follow-ups (#102, #105, #106). - **Arc 2 (editing table stakes) COMPLETE** — query-replace (#97), kill ring + `M-y` (#103/#105/#106), comment-toggle (#107), auto-indent (#109), auto-pairing (#110). - **Arc 3 (persistence) COMPLETE** — saveplace/recentf (#98), desktop-save (#99), autosave/crash-recovery (#100), save-clobber fix (#101). - **Arc 4 (themes + extensibility) COMPLETE** — named UI faces (#120), live GPU font preferences (#124), statusline providers (#125). - **Arc 5 terminal stage COMPLETE** — compile mode (#113), Vterm terminal core (#126), TUI frontend (#130), and protocol/GPU Stage 3 (#135) landed. - **Config registry COMPLETE (#127)** — not a numbered arc; it was the cross-cutting substrate ranked first on `docs/side-quest-backlog.md`'s north star, and it unblocks the editing/indent/comment items that were config-blocked. - **Mode system wiring COMPLETE (#129)** — major-mode keymaps, introspection, lifecycle initialization, and statusline display shipped. - **Locals-query processing COMPLETE — #134** — grammar locals metadata, lexical resolution, settled per-layer facts, shared TUI/GPU local-predicate filtering, and a registry-wide locals-query invariant shipped without a protocol change. - **Arc 6 (folding) Stages 1 and 2 LANDED — #142 and #149** — the headless fold engine (store, structural source, Lua `C-c @` surface, command-path unfold, `FoldState` production), then the grid/daemon collapse (the `VisibleLineMap` spine, fold-aware gutter/diagnostics/caret/selection/ presence/viewport/motion, and the interactive unfold widening). **Stage 3 (GPU) is next**, unframed. - **Web grammars HTML+CSS LANDED — #146**, and **LaTeX Stage 1 — #144** with its inline-math parent framing **#145**. - **Arc 7 (bottom panel) Stage 1 LANDED — #155** — window placement, window parameters, TUI side windows, the divider, and the adopter `display` opt-in. **Stage 2 (the GPU band) is next and needs its own re-framing**; Stage 3 is the default flip. DAP was parked awaiting exactly this arc's Stage 1 and can now re-baseline its touch census. - Remaining ranked arcs: 6 folding Stage 3, 7 bottom-panel Stages 2–3, DAP, 8 GPU splits, plus the `.ipynb` arc (its JSON-grammar prerequisite shipped in #123). - **GPU terminal input LANDED — #166** (`main` @ `b889873`; `docs/gpu-terminal-input-framing.md` rev 2; one review round). The dispatcher applied **both** terminal-layout syncs to **every** attached frontend each tick. A semantic session satisfies both conditions — a `term_sizes` entry from `AttachRequest` *and* a terminal declaration — so its PTY was resized twice per tick forever: the grid arm installed the TUI placement size, the semantic arm the declared content rectangle, each arm's `old_size == size` guard seeing only what the other had just written. The child took a `SIGWINCH` storm at tick cadence, which made typing into a GPU terminal impossible while output kept flowing. TUI was structurally unaffected. - `EditorInstance::sync_terminal_layout` is split into `sync_terminal_controller_liveness` (frontend-kind **neutral**: panel reconcile + release of a controller whose window moved away — reads only views/windows/controller, never a grid size) and `sync_terminal_grid_geometry` (**grid only**: TUI placement + resize). `sync_terminal_layout` survives as the composition, so `editor::run` and `LOCAL` are byte-identical. - `daemon::sync_terminal_layouts_for_tick` is the extracted loop body: liveness for every frontend once per tick, then **exactly one** geometry arm keyed on `semantic_states` membership — the same fact session establishment uses, so the arms cannot both fire. - **The trap, kept in a comment:** the release on a missing `window_placements` entry reads like liveness and is grid geometry. A semantic frontend has no placement entry at all, so moving it into the neutral half would release a GPU controller every tick. - Why not the one-line guard: the grid arm was also the **only** per-tick controller-liveness release a semantic frontend got, and `sync_semantic_terminal_layout` cannot take it over — the buffer-follow snapshot clears the viewport declaration, so that arm stops running in exactly the switch-away case that needs the release. - No protocol change (v20). Gates: 1,829 default + 2,006 CRDT library tests; vterm Stage 1/2/3 10/6/9 CRDT; bottom-panel 46; M4 121; required GPU 155; isolated-config workspace sweep 3,177 across 92 suites. - **Known gap, its own lane:** CI never enables `crdt`, so the Stage 3 real-path acceptance (including `a37`) is not compiled there. #166's unit pins are not `crdt`-gated and do run. See `docs/active-work.md`. ## 2. How we work (the part that must not drift) The user is expert and reviews deeply — they falsify framings and find real bugs in round after round. The cadence that has worked for ~40 PRs: 1. **Scout ground truth** in the code before proposing anything. 2. **Write a framing doc** — `docs/-framing.md`, numbered decisions (`Q#XY1…`), explicit "Ground truth", "Bets", "Deferred (named)", and an acceptance-test list. Present it and **wait for explicit approval** ("Go for it" / "Ready to roll"). Expect 1–3 rounds of findings first; revise the doc, don't argue. 3. **Branch off main** (one feature = one branch = one PR). Commit the framing as the first commit. 4. Implement. **Every reviewer finding gets a bite-verified fix** — a test that fails without the fix. Watch for vacuously-passing tests. 5. Run the full gate suite (§3). Open the PR with `gh`. 6. The user replies with "Findings" lists on the PR rounds too. Same discipline. They say when to merge — **never merge unprompted**. 7. After merge: update this handoff + your memory. Commit/PR conventions: commit messages via `git commit -F ` (no inline backticks through the shell). **Authorship trailers and PR attributions must be truthful:** do not add a Claude co-author trailer or Claude Code attribution unless Claude actually contributed. Clippy runs as its own step, never `&&`-chained. ## 3. Gate suite (all green before any PR) **Run it with `scripts/gate`. Do not retype it.** ``` scripts/gate [--acceptance SUITE]... [--protocol] ``` The script is **authoritative for the fixed executable gates** — the list below is what it runs. **This section stays authoritative for policy** (everything under "Every part is load-bearing", the protocol-bump rule, the machine-specific caveats) **and for CHOOSING the touched acceptance suites**, which reach the script only through `--acceptance`. No script can infer those from a working tree, and one that guessed would report coverage it does not have. Three things it does that a retyped command line kept failing to do: - **A per-worktree `CARGO_TARGET_DIR`.** This machine exports one globally, and cargo locks it exclusively — two worktrees building at once serialize and thrash each other's artifacts, making parallel lanes *slower* than serial. Note the trap: the environment variable **overrides** `build.target-dir` in any `config.toml`, so a per-worktree config file silently does nothing. - **All five ambient roots** (§ the caveat below), fresh per run. - **Every gate's full output to a durable log**, with the sweep paths printed. This is the U2/U3 remedy: both registry notes exist because a sweep was piped through `grep` before anyone read it, and the fragments a `docs/ci-red-signatures.md` row needs were gone. **Read the log; do not re-run and filter.** `scripts/gate --print-plan` prints the commands without running them; `tests/gate_script_acceptance.rs` asserts that plan still matches this section, so the two cannot drift silently. `--init` prepares a worktree's build directory; `--prune` reclaims directories whose worktree is gone (dry-run unless given `--force`). Framing: `docs/gate-script-framing.md`. It is a **convention, not an enforcement** — a bare `cargo test` still takes the shared lock. Nothing in-repo can change that while the variable is exported globally. What it runs: ``` cargo fmt --check cargo clippy --workspace --all-targets -- -D warnings # own step cargo test --lib # ~1500 cargo test --lib --features crdt # ~1672 cargo test --test # --acceptance cargo test --test m4_acceptance -- --skip basedpyright PMACS_REQUIRE_GPU=1 cargo test -p pmacs-gpu # 58 cargo test --workspace --no-fail-fast -- --skip basedpyright # sweep git diff --check ``` **`--no-fail-fast` is now on the normal sweep too**, not only the protocol-bump form below. The reason given there — *"cargo stops at the first failing target: without it a bump that breaks eight assertions reports one"* — was never specific to bumps; a lane that breaks three unrelated targets has the same problem. The cost is paid **only on red**: a green sweep is byte-for-byte the same work. **The full sweep is not optional, and `CLAUDE.md`'s shorter list is not a substitute.** That list stops at "the touched acceptance suites"; this one continues. Long-lines Stage 3 followed the short form and put eight broken version assertions on CI. When the two disagree, **this list wins**. **Touching `PROTOCOL_VERSION` STRENGTHENS the sweep line. It does not replace it — and the crdt sweep has a BUILD PRECONDITION:** ``` cargo test --workspace --no-fail-fast -- --skip basedpyright cargo build --workspace --no-default-features --features luajit,crdt cargo test --workspace --features crdt --no-fail-fast -- --skip basedpyright ``` Every part is load-bearing: - **The build before the crdt sweep is a PRECONDITION, not a courtesy, and it is gate policy rather than an ops tip.** The crdt sweep spawns `pmacs-gpu` as a *process*, and no `cargo test` run produces that binary: `pmacs-gpu` has no `tests/` directory, so cargo never uplifts its bin to `debug/pmacs-gpu`. Omit the build on a cold target directory and twelve `gpu_invocation_acceptance::crdt::*` tests fail on *"build pmacs-gpu before this acceptance suite"* — and, worse, crdt tests that drive the real binary (`vterm_stage3` a37, `bottom_panel_stage2b_gpu` a54) take their skip branch and report **`ok`**, so the missing build also voids coverage *silently*. `scripts/gate --protocol` emits it as its own named `build-crdt` step, never folded into the sweep command, so a build failure is attributed to the build rather than to the sweep. **Only the crdt sweep needs it, and that is MEASURED rather than reasoned.** On 2026-08-09, on a disposable target directory with `debug/pmacs-gpu` asserted **absent before each run** and each sweep run alone from that cold state: the **default** sweep exited **0** (114 test targets green) and left `debug/pmacs-gpu` **still absent** — it never builds the binary and never needs it — while the **crdt** sweep exited **101** with exactly those twelve failures. An unconditional build would be a real cost paid for nothing on every ordinary lane. **Why this was latent for years.** Before per-worktree target directories (#225) every worktree on this machine shared one, which nearly always already held a `pmacs-gpu` from some earlier build, so the precondition was satisfied **by accident** on essentially every run. The hazard is not the red gate — a red gate stops you. It is a **green** `--protocol` run whose crdt sweep was decided by what happened to be in the build directory rather than by the diff, which is a gate reporting coverage it does not have. §5 keeps the incident and its signature as history; **this section owns the requirement.** - **`--workspace`, never `--tests`.** `--tests` selects 108 targets where `--workspace` selects 110, and the two it drops are **`pmacs_protocol` and `pmacs_gpu`**. On a protocol bump, dropping the protocol crate's own unit tests is precisely the wrong loss. Long-lines Stage 3 swept with `--tests` and so never ran `pmacs-protocol`'s 25 tests — including the `scroll::classify` tests that same lane had just written. They passed, but by luck. - **`--no-fail-fast`**, because cargo stops at the first failing target: without it a bump that breaks eight assertions reports one. - **`--features crdt`**, because crdt-gated real-daemon tests assert on a live socket's negotiated version and are invisible otherwise. - **`-- --skip basedpyright`** for the same reason the line above carries it. See §5's protocol-bump bullet for how to sort the failures this finds — some are tripwires doing their job, and one pin (`ADVERTISED_PROTOCOL_VERSION`) must never be edited at all. Machine-specific caveats — re-verify on a machine you haven't used before trusting them: - **Ambient storage roots: control all FIVE, not four.** **`scripts/gate` does this for you** — it is only stated here because the reasoning has to live somewhere, and because a run done by hand still needs it. **The ambient-root isolation implementation MERGED as #206**, so the in-crate paths resolve roots explicitly rather than from the caller's environment; the earlier text here still said "until the lane lands", which stopped being true at that merge. What the five variables cover now is everything *outside* that guarantee — integration suites that spawn the real binary, PTY and daemon fixtures, anything reaching a production resolution path — where the process under test reads the environment it was handed. Belt and braces: a gate run that scribbles in the developer's real config or data root is a bad failure mode whether or not the crate promises not to. A local full-suite run done by hand therefore needs, all pointed at a fresh directory: ``` XDG_CONFIG_HOME XDG_DATA_HOME XDG_STATE_HOME XDG_CACHE_HOME PMACS_STATE_HOME ``` **The fifth is not redundant.** `PMACS_STATE_HOME` outranks `XDG_STATE_HOME` (`src/state.rs`), so redirecting the four XDG variables on a machine that exports it leaves the real state root live. `HOME` is deliberately left alone: it is the fallback for the XDG roots (already covered once they are set) and separately drives `~`-expansion, which `find_file_acceptance` pins on purpose. A run isolating only `XDG_CONFIG_HOME` stops the `init.lua` reads and still writes through the real data root — every local gate run in this repo before 2026-07-31 had that hole. **After the lane lands** the in-process population isolates itself through `EditorState::new_with_roots(&crate::iso::roots())` and the five variables are belt-and-braces rather than required. - **basedpyright**: the desktop binary was **never broken** — this was a real code defect, diagnosed and fixed 2026-07-29 (see §5, "A `Drop` body runs before its fields"). `RuntimeHandles::drop` joined its reader threads before the `stdin` field dropped, so the server never got stdin EOF, never exited, and kept the output pipe the readers were blocked on. Deterministic on the desktop, invisible on the laptop and in CI, which is why it read as a broken local binary for weeks. **How the orphan is actually made — WE make it.** basedpyright's console script runs bundled `node` through `subprocess.run` and **waits** (`nodejs_wheel/executable.py:50`, verified in 1.39.6). At teardown `shutdown()` SIGTERMs the *recorded* pid — the Python wrapper — which dies without forwarding the signal, orphaning node to `PPid 1` holding the pipes. An earlier revision of this entry said the wrapper "spawns node and exits"; that was wrong, and the refutation was already in hand, since the initialize handshake succeeds, which a wrapper that exited at spawn could not have done. The consequence is for the follow-up, not the fix: the orphan-management work is **stop orphaning them** (signal the group), not tolerate self-orphaning. The `--skip` above stays for now: it is still correct on any tree predating the fix, and — the one live reason — **CI never installs basedpyright at all**, so arming `PMACS_REQUIRE_PYRIGHT` would fail rather than test anything. The two original reasons are both gone: the hang is fixed, and #195 gave every job a `timeout-minutes`, so a hang can no longer burn six hours. Installing basedpyright in CI (a uv plus bundled-node download per leg) and dropping the local skip are two separate proposals, each owed its own evidence. - **GPU on the laptop**: AMD Radeon 780M (RADV) — native Vulkan, `PMACS_REQUIRE_GPU=1` works without lavapipe. - **Flaky-under-load tests — what this lane OBSERVED.** *(Historical record. This bullet no longer states a triage rule: for judging a red run, `docs/ci-red-signatures.md` is the authority, and its rule supersedes "rerun isolated" — a green rerun establishes intermittence only, never environmental cause. `m6_8_supervisor_reaps_all_children_across_cycles` is **A2** there — an audit note, not a matchable row, because no signature was ever captured.)* The m8 daemon tests and the m6 process/PTY tests (`m6_1_pty_mode_lifecycle_started_then_exited`, `m6_8_supervisor_reaps_all_children_across_cycles`) are timing-based; `editor::composition_overhead_under_ten_percent` is a render-ratio microbenchmark that fails ~1/3 even isolated single-threaded (already `cfg!(macos)`-disabled). *(Local measurements, 2026-08-05, 16-core Linux, tree-primitive branch, which could not reach it — its diff versus `main` touches no `src/`, no crate, no manifest. **Two reds, both inside the full `--features crdt` lib run**, at `dispatch overhead` 30.7% and 10.3%; two full-suite runs at the same tips were green; and **10/10 green run alone**, ratios spanning -2.3% to +1.5%. So the in-suite/isolated split has now been seen twice, and the second red cleared the 10% budget by 0.3 points — the threshold is marginal, not comfortably clear. Recorded as measurements, NOT a cause: ten isolated greens establish that the ratio sits nowhere near the threshold when alone, not that in-suite contention is what pushed it over, and two reds against two greens in-suite is intermittence rather than a mechanism. Not a `ci-red-signatures.md` row either — that registry judges red **CI** runs, and these were local.)* Vterm Stage 3's merge CI saw one macOS timeout in `real_tui_terminal_smoke_restores_host_after_output_input_resize_scroll_copy_and_bell`; the complete failed-job rerun passed. The required-GPU gate also failed once in `headless_diag_face_recolors_band_counter_despite_unchanged_text`, then passed both an isolated single-thread rerun and the full 139-test rerun. *(That "rerun the test alone before investigating" instruction is retired — an isolated green reproduces nothing about a load-sensitive failure and establishes intermittence at most. See the registry's rerun rule.)* Run the workspace sweep as ONE `cargo test` invocation piped to a full log — a double invocation + `grep -c "test result: ok"` can mask real failures with a misleading `0`. - **GPU tests** need a Vulkan device. `PMACS_REQUIRE_GPU=1` makes absence a hard failure instead of a silent skip. Headless option: lavapipe (see `docs/repository-audit-2026-07-03.md` for the CI harness how-to). On a laptop without discrete GPU, mesa/lavapipe works. - **The desktop's shell is fish** (no `$(...)`, use `(...)`; no `$UID`, use `(id -u)`). Check `$SHELL` here before assuming. ## 4. Substrate invariants (do not undo; tests enforce most of these) **Generated buffers: `Buffer::set_generated_contents` is the ONE authorized write** (terminal copy mode #178) — lift `read_only`, replace via a single whole-buffer `Replace` skipping intercepts, discard history, re-assert `read_only`, and **return the `Edit`**. Three things make it a unit rather than a convenience: - **An intercept is not read-only.** `Buffer::undo` reaches the rope through `ensure_writable` and never consults the intercept chain, so an intercept-only "read-only" buffer is emptied by `M-x buffer.undo`. Rebinding the undo *chords* buffer-locally does **not** close it — `compile.lua`'s own comment says so ("command/menu undo stays dispatchable"). Only rope-level `read_only` does. - **A bare `set_read_only` would be worse than nothing**, because it also refuses the owner's refresh — the operation such buffers exist for. That is why the pairing, not the setter, is the primitive. There is deliberately no Lua `set_read_only`. - **A rope write is only half of an edit.** The returned `Edit` must be fanned out (`notify_buffer_edit_to_windows`, which also queues the daemon-origin CRDT op). Skip it and a displaying window keeps a `TextView` line index describing the previous contents — the next paint indexes the new rope with stale ranges and trips `assertion failed: end <= self.len()` — while replica mirrors never import the write at all. History clearing is load-bearing twice (nothing can pop entries `read_only` makes unreachable, so they leak), and must clear **whichever history the buffer has**: the v0.1 stacks are bypassed in CRDT mode, where it lives in loro's `UndoManager`. That has no `clear`, and needs none — a manager records only what happens after construction, so `CrdtState::clear_undo_history` rebinds a fresh one to the same doc. **Not yet adopted — the inventory is four writer mechanisms covering five buffers.** *Every remaining intercept-protected writer* uses the older idiom: an erroring intercept plus `set_round_trip_input`, written through `bypass_intercept`, with the rope left writable. All are emptiable by `M-x buffer.undo`: | writer | buffers | shape | |---|---|---| | `builtin/runtime/listview.lua:60-61` | every listview panel | delete-all + insert | | `builtin/runtime/compile.lua` (`ensure_slot`) | `*compilation*`, `*shell-command*` | **append** per output batch | | `builtin/commands/default.lua:869` | `*search-results*` | reset per query, then **append** per match batch | | `builtin/runtime/dired.lua:371` | every dired buffer | whole-buffer replace | **Do not read `ensure_slot` as covering the search panel** — it serves `*compilation*` and `*shell-command*` only (`compile.lua:1090,1125`). `*search-results*` is an independent panel with its own intercept, round-trip mark and writes, and `compile.lua` names it only in a predicate. Nor is the scope "every generated buffer": `*workers*`, `*help*` and `*buffer-list*` are generated too but do not use this idiom, and the REPL package's intercept (`builtin/packages/repl/init.lua:187`) is an op-filtering editing policy, not a read-only panel — neither group belongs to this lane. Adoption is not a one-line swap. It inherits the fan-out obligation, and the three appending buffers need a **streaming variant** of the primitive; listview and dired already write whole-buffer replaces and are the cheap half. Recorded in `COHERENCE.md` §14. **And it does not replace `set_round_trip_input`.** The protection is layered across two copies: rope-level `read_only` refuses the op at the daemon; round-trip input stops a semantic frontend applying optimistically to its **own mirror**, which a daemon-side refusal cannot reach — the refusal arrives after the frontend has already painted, so it buys divergence, not prevention. **Command boundaries (Arc 2 kill-ring substrate)** — `EditorCore.command_history: HashMap`, per frontend. Rotate on: keybound command, self-insert, menu invoke, `invoke_interactive` (the M-x path). Break on: unbound key, GPU optimistic CRDT edits, pointer gestures (wheel scroll deliberately does NOT break), unified paste. **Plain `pmacs.command.invoke` stamps nothing** (programmatic API); `invoke_interactive` rotates-then-invokes (Emacs M-x semantics). Single-codepoint optimistic CRDT inserts classify as `buffer.self-insert` (exact decode; `"a("` breaks instead). Lua: `ed.this_command()` / `ed.last_command()`. **Effective-edit returns** — `buf:insert/delete/replace` return the post-intercept `(start, end, inserted_len)`. Callers that care (killring, comment) compare EXACTLY against the request; length-delta and text-at-position checks are documented defeated patterns. Always `pcall` the mutator: a rejecting intercept must report, not throw through, and failed ops must leave no state (kill chains, yank sessions). **Kill ring** — entries `{id, text}` with stable monotonic ids; chains and yank sessions are per-frontend and id-checked (an index is not stable under other frontends' pushes). OS clipboard mirrors to the acting frontend only. Paste is a unified daemon arm keyed by the dispatcher's AUTHENTICATED source — never a payload frontend_id. **LSP outbound positions** — every Position/Range builder in `src/lsp.rs` routes through `outbound_position` (byte → negotiated encoding). Any new request builder must too; UTF-16 servers reject raw byte columns on non-ASCII text. Semantic tokens: `full`, `full.delta`, and `range` are three INDEPENDENT capabilities — gate each. **Persistence (Arc 3)** — state-dir wiring lives in `install_state_dirs()` on real entry points only, NOT `EditorState::new()` (tests stay hermetic); `PMACS_STATE_HOME` overrides. Autosave: one buffer owns a path's recovery slot; only recover/discard release unclaimed crash data; adopt clears the old owner's skip cache. **Protocol** — encoding-breaking bumps are deliberate and versioned. Canonical `main` is `[6..=20]`. The in-review bottom-panel 2B-1 schema extends support to `[6..=21]`, while `ADVERTISED_PROTOCOL_VERSION` stays 20 until 2B-3 provides compatibility-preserving activation; the server-first `Hello` cannot advertise 21 without stranding existing v20 clients before `AttachRequest`. v15 = `CompletionPopup` + `StatusFacts.message`; v16 = `ThemeFacts`; v17 = `FontFacts`; v18 = `StatuslineSegments`; v19 = the vterm terminal family; v20 = semantic `SessionBootstrapRequest` plus appended `InitialTargetResult`; v21 reserves the panel frame/event family; v22 = `LineWrapFacts`; v23 = `MinibufferPromptRows`. New wire surface ⇒ bump + both-frontends support + acceptance. An APPENDED variant must be guarded by a byte pin on the PREVIOUS final variant — its own round-trip cannot detect a discriminant shift. **A SUPERSEDED variant can be frozen rather than widened, and v23 is the first case.** Discovery Stage 2 needed richer minibuffer rows. Widening `MinibufferPrompt` in place was not an option — postcard encodes fields positionally, so every v12–v22 peer would **mis-decode** the bytes rather than ignore them — and gating the widened form at `>= 23` would have left those peers with **no minibuffer message at all**, because there would have been only one variant to gate. Compatibility requires the old shape to still exist *and still be sent*. So `MinibufferPrompt` is retained unchanged for `12..=22`, `MinibufferPromptRows` is appended for `>= 23`, and the daemon gate is a **range on both sides** so exactly one variant reaches any peer. Two consequences worth carrying forward: a frozen variant needs a **literal byte fixture** (`assert_eq!(encoded, LEGACY_BYTES)`), because a round-trip encodes and decodes with the same types and so freezes nothing; and the CLOSE message must use the same variant family as the OPEN, or a session closed by the other family's clear leaves its surface on screen forever. **Fake LSP** (`src/bin/pmacs_fake_lsp.rs`) modes: `fullonly`, `rangeonly`, `rangeonly16` (UTF-16 + fail-closed bounds validation), `sighelp`. Use these for capability-matrix tests, not real servers. ## 5. Hard-won ops lessons - **An optional field that a data structure's shape depends on is not optional.** `listview` rows may omit `item`, so `line_to_item[n] = row.item` leaves that map **sparse** — and `seat_cursor` took `#` of it, which for an all-display-only tree is 0, stranding the cursor on the header where TAB finds no row. The whole existing suite missed it because **every test supplied `item`**: the field was optional in the API and mandatory in practice, and nothing in a passing run distinguishes those. When a field is optional, write one test that omits it — the sparse-table `#` is a Lua-specific trap, but "optional in the signature, required by the shape" is not. - **A contract two mechanisms must honour is only as strong as the weaker mechanism.** `listview` ids were documented "opaque, compared by equality". Selection compares with `==`, honouring `__eq`; collapse state stores ids as **table keys**, and Lua indexes tables by raw identity, consulting no metamethod. A table id satisfied one half and silently failed the other — a refresh would restore the cursor and lose the fold, surfacing arbitrarily later with nothing pointing at the id. **Narrow the contract to what both halves can honour and enforce it where the data enters**, rather than generalizing the strong half to match the weak one: equality-aware collapse lookup would have turned a linear render quadratic to support a key type no consumer wanted. The same pass found the contract said "identity" while accepting duplicates (every lookup takes the first match, so selecting the later row toggles the earlier) and "number" while accepting NaN (a number Lua refuses as a key). **Enforcement and documentation drift apart silently; only the enforcement is real.** - **Match a red by its required fragment, never by test name or resemblance.** An occurrence scan on 2026-08-06 nearly filed `main` run 30710662474 as **R3** — same test, same `EPERM`, same `measured_group=unobservable(ESRCH…)`. R3 requires `leader=live`; that run reads `leader=exited(signal SIGUSR1)`, which is **R2's** exact fragment, four days before R2 was retired. The two rows are a live possible **product defect** and a fixed **test race** in the same test, and only the fragment separates them. A second red in the same scan was filed as **R5** rather than folded into R1 for the same reason: both are supersede under a deadline on macOS, and **sharing a subject is not sharing a signature**. - **A retired row's recurrence rule is about time, not just text.** A red matching a retired row falsifies the retirement **only if it postdates it**. An earlier occurrence found later corroborates the row instead — and can still add something: 30710662474 is macOS *luajit* where R2's evidence was *lua54*, so the mechanism was never flavor-specific. - **A gate summary assembled through a pipe can report success over a failure.** `cmd | tail -2` returns **`tail`'s** exit status, not `cmd`'s — in `fish` and `bash` alike — so a chain of `cargo test ... | tail -2 && cargo test ... | tail -2 && echo "ALL GATES CLEAN"` prints the clean line even when a suite failed. This is not carelessness that closer reading would catch: the failure is **structurally invisible** in the summary the PR then cites. It happened while gating the silent-skip lane, and a `pmacs-gpu` failure was reported as clean. Either check `$pipestatus[1]` in fish (`${PIPESTATUS[0]}` in bash), or — better — redirect each gate to a file and read the file afterwards, which also preserves the full log this section already asks you to keep. Same family as the skip-reports-`ok` lesson below and the double-invocation traps: **the thing that summarizes a gate must not be able to lose the gate's verdict.** - **A reproduction is a measurement, and needs its own positive control.** The basedpyright-hang lane wrote **four** reproductions that passed against the *unfixed* tree, each vacuous for a different reason: the child exited before the join; the child never read stdin at all; the child's stdin was silently rebound to `/dev/null` (POSIX XCU §2.9.3 assigns `/dev/null` to an asynchronous list's stdin when job control is off, so `sh -c 'cat & exit 0'` EOFs instantly); and then **the repair for that was also wrong** — the rule applies *before explicit redirections*, so `<&0` duplicates `/dev/null` onto itself. `bash` skips the default when a stdin redirect is present, `dash` does not, so `<&0` passed locally and failed in CI. The shipped test uses `setsid --fork`, removing the shell from the reproduction entirely. Every one of the four looked obviously right when written, and the fourth was verified locally before it failed. Note what a narrower rule would have missed: "check the child is still alive" catches only the first. Only the general form catches all four — **and the ones nobody has invented yet.** Note also which mechanism caught the fourth: not a reviewer, but the control itself, failing loudly in CI and naming its own cause. So: assert the precondition your reproduction depends on, in the test, before exercising the thing under test. In `teardown_closes_stdin_before_joining_readers` that is two controls (the recorded child has exited; both readers are still blocked in `read`), each with a failure message naming what its absence means — and a `/bin/sh` that is `bash` locally and `dash` in CI is exactly the sort of divergence no amount of local verification reaches. This is the same rule that produced #192's bite positive control and #194's re-read-the-artifact lesson, stated at full generality: **a measurement you have not controlled is a claim, not evidence.** - **A `Drop` body runs before its fields, whatever the declaration order.** Cost a multi-week misattribution: `RuntimeHandles::drop` joined its reader threads in the drop *body*, while the `stdin` sink it needed to close first sat in a *field* — reachable only after that body returned. The child never got EOF, never exited, and kept the output pipe the readers were blocked on, so teardown hung forever. Reordering the struct's fields cannot fix this shape; the operation has to move into the body. Generally: **if a `Drop` body waits on anything, check what the waited-on party needs that only a field drop will release.** Corollary from the same investigation — `cancel`-flag style wake-outs only work where the thread actually polls them; a thread blocked in a raw `read` never sees one, so a flag next to a blocking syscall is documentation, not a mechanism. - **A test that skips on a missing precondition reports `ok`, and a gate log cannot tell that apart from a pass.** `vterm_stage3_acceptance::a37` — the only acceptance driving a real daemon, a real PTY and a real wgpu render together — derives `pmacs-gpu` from `CARGO_BIN_EXE_pmacs` and, when that binary is absent from the target directory, prints a skip and returns. A fresh worktree reports the suite 9/9 **in 0.17 s having never run it**; a real run takes ~4 s. `PMACS_REQUIRE_GPU=1` is what promotes the skip to a failure, and the standing gate list applies that flag to `cargo test -p pmacs-gpu`, a *different package*. Two habits follow: build the workspace before believing any suite that reaches for a sibling binary, and **judge such a suite by its elapsed time**, not its verdict. - **Before attributing a red test to your branch, run it on the merge base.** `a37` failed on the #173 branch, which looked like a regression; it failed identically on the PR's own base and on two intermediate commits, and had *passed* on that same base twenty minutes earlier. The variable was machine load from a second agent compiling continuously. Load-sensitive tests make both verdicts uninformative in isolation, so the base-commit run is the cheapest way to tell a regression from weather — and it is much cheaper than the bisect it replaces. - **A daemon-side fix is not deployed until the daemon is restarted from a tree that contains it.** #166's reporter rebuilt and saw no change: the running daemon had been started from a shared checkout still on a pre-fix branch, and `pmacs --gpu` attaches to whatever process already owns the socket. Rebuilding a binary does nothing to a running process. When validating a daemon-side fix by hand, check the running process's binary path and start time against the tree you think you fixed — `ps -eo pid,lstart,args | grep '[p]macs --daemon'` — before concluding the fix failed. - **Two operations that must be alternatives are not made alternatives by being adjacent.** The dispatcher applied its grid and semantic terminal-layout syncs to every attached frontend; a semantic session satisfies both conditions, so its PTY was resized twice per tick forever and the child took a `SIGWINCH` storm that made a GPU terminal untypable while output still flowed. Each arm had a correct `old_size == size` idempotence guard — **individually sound, jointly useless**, because each saw only the size the other had just written. Write mutually exclusive per-frontend-kind work as one `if`/`else` keyed on the same fact session establishment uses, and extract the loop body so a test can drive the real thing. - **Bite against every pre-image the fix could plausibly have taken, not just `main`.** For the same defect, the obvious one-line guard (skip the grid arm for semantic frontends) *does* fix the storm — and silently introduces a controller leak, because that arm was also the only per-tick controller-liveness release a semantic frontend got. A single revert would have scored the fix complete. The pin that catches it (`acc 6`) deliberately **passes on `main`** and fails only against the naive guard: today's defect supplies the release by the accident of running an arm it should not. - **A quiet child is an instrument.** A frame storm is invisible against a fixture that legitimately emits hundreds of frames, and an assertion like `frames >= 2` cannot see one. The same applies to geometry: a "did a frame at the new width arrive" readout is satisfied by a geometry *oscillating through* that width. Assert upper bounds over a fixed window against a child that produces nothing, and let the child self-report the signal you care about (a `SIGWINCH` trap printing a **fresh distinct** breadcrumb per signal — repeated identical markers paint nothing, because `cell::diff` skips already-matching cells). - **`TerminalMode::Raw` makes `sh`-based input fixtures useless.** There is no `ICRNL`, so Enter delivers CR and a `read -r` loop waits forever for a LF that never comes — the test then "proves" input never arrived. Use `exec cat`, which copies stdin to stdout byte by byte. It is also the right echo instrument for the opposite reason people assume: termios `ECHO` is *off* in raw mode, so nothing double-echoes and one keystroke yields exactly one cell. - **Draining the event stream to learn a pid also TICKS, and a tick reaps.** #176's `observing_the_leader_does_not_consume_the_exit_event` failed under load with "process ProcessId(26) is not running": its helper drained for `Started` to read the pid, `drain_until` ticks while it drains, and a tick can observe an immediately-exiting child and move the record out of `Running` — after which `signal` never reaches the code under test at all. It passed standalone only because the drain returned on `Started` before `poll_one` saw the exit. Read the pid **straight from the supervisor record**, which does not tick, and fail fast if the record has left `Running`. **Verified load-bearing under matched load: 0/15 failures with all 16 cores saturated versus 1/10 for the ticking helper.** The general rule: an observation helper that advances the system is not an observation. - **A wait predicate that is WEAKER than the assertion it guards is a race, on every platform that happens to lose it.** #174: the m4 config sink test waited for `contains("probe")` and then asserted `"probe":true` — six bytes further on. The sink is JSONL written by a *separate process*, so the test could read a half-written line; Linux won that race reliably and macOS/lua54 did not, reporting the truncated `{"rust":{"probe":`. **Any "wait until the file mentions X, then assert Y about the file" shape races whenever Y is stricter than X.** The fix is to wait for the exact unit the assertion reads — here a trailing newline, true only once a whole `writeln!` record has landed, and still correct if the payload's field order or spelling changes. Two things generalize beyond the fix: - **A race you cannot reproduce can still be bitten at one remove.** The failure needs a scheduler outcome Linux does not produce, so no local run falsifies it. But `pump_async` *asserts* on its deadline, so replacing the predicate with an unsatisfiable one proves the wait is load-bearing rather than decorative — and restoring the *old* predicate, which still passes locally, proves a green local run cannot distinguish the two. Bite what you can reach and say plainly which claim rests on structure instead of evidence. - **The obvious fix is sometimes worse.** The sibling `m4_26` has the same weak shape and was deliberately left alone: waiting for the expected value would convert a genuine `rootUri` regression — what its `assert_ne!`s exist to catch — into a five-second timeout with a misleading "server didn't initialize?" message, trading a precise assertion diff for a vague hang. Closing it properly needs a record terminator in the fake server first. - **Proving a child has exited is harder than it looks on this codebase.** A fixed sleep is not proof; nix's `waitid` is unavailable on macOS; and `libc::waitid` needs `unsafe`, which `#![forbid(unsafe_code)]` rules out. What works is driving the production diagnostic in a **bounded loop until it observes the exit**. Relatedly, #176's round-1 review replaced every substring assertion with exact message equality built from the kernel-assigned pid — the substring forms would have accepted a hardcoded target or a wrong exit code. - **The checkout may be shared with the user.** Check `git status` for foreign uncommitted work before any stash/checkout/branch surgery; never assume dirty files are yours. (Their uncommitted fix was nearly orphaned once.) A clean status goes stale within minutes when two lanes are active — for parallel work, `git worktree add` a sibling directory off main instead of switching the shared checkout. - **Never `git stash` in this repo.** The stash namespace is REPO-GLOBAL — one list shared across every worktree and with the user; a scripted push/pop can pop a human's years-old stash into your tree (happened during #111: a failed `stash push` chained into `stash pop`, which grabbed the user's PR-#17-era entry). For run-tests-against-an-old-version swaps, use `scripts/bite` — a trap-guarded one-file swap over read-only `git show`, with a two-sided verdict (the tests must PASS now and FAIL against the old version), making bite-verification machine-checkable. - **`scripts/bite` is only as good as its positive control, and it had none until it was given one.** Before that it ran *only* the swapped tree, so it could not tell "my fix is load-bearing" from "my test is broken": a test that fails everywhere made the swapped run fail, and a failing swapped run was the only thing checked, so it printed `bite: OK` and certified nothing. It now asserts the named tests pass **and** that at least one actually ran (a filter matching nothing exits 0, so passing alone is not enough), exiting 3 as `NO CONTROL` otherwise. It also distinguishes `OK (assertion)` from `OK (COMPILE)` — an old file that does not build against the current tree is a much weaker result, because the tests may never have run at all. **Read which one it printed.** - **A fix must be COMMITTED before it is bitten** — but *not* for the reason previously recorded here. This file used to say `scripts/bite` "restores by `git checkout --`, which reverts the file to HEAD", and that a review round's fixes were wiped that way during #165. **That mechanism description is false and was verified false:** the script copies the file to a `mktemp` path before the swap and restores from that copy, under an `EXIT INT TERM` trap, so uncommitted work in the bitten file survives. It has never touched git state beyond a read-only `git show`. The rule still stands on its own merits — gate results must describe the pushed tree, and a `cargo fmt` after a commit splits worktree from branch — but do not repeat the destroys-your-work claim, which will push the next reader toward `git stash` to protect themselves, straight into the repo-global trap above. **The #165 incident itself is now unexplained**, and that is recorded rather than papered over: work really was lost, but not by the mechanism this file blamed. A `SIGKILL` bypasses the trap and would leave the swapped file in place, which is one candidate; so is a stash collision, given the same round. Do not invent a mechanism to close the gap — an unexplained incident is safer than a confident wrong cause, which is what produced this correction. Corollary for a NEW file: the swap-over-`git show` mode does not apply at all, so its claims must be bitten by hand-editing. - **A CONFLICTING PR silently runs no CI at all.** GitHub builds `pull_request` workflow runs against the PR's **merge ref**, which it does not create while the branch conflicts with its base. So pushes land, the branch updates, no run is ever queued, and **nothing reports the absence** — the checks list simply keeps showing the last successful run, which reads as current. Three pushes to #165 produced zero CI before the cause was found, and `gh pr checks` returns nothing usable here. On any lane that lives through a moving `main`, check `gh pr view --json mergeable,mergeStateStatus,headRefOid` and confirm a run exists **for the current head sha**, not merely that a recent run was green. - **Stacked PRs**: retarget the child to main BEFORE merging the parent — GitHub auto-closes a PR whose base branch is deleted and cannot reopen it (#104 → re-opened as #105). - **Frozen reviewed PRs do not absorb moving overlapping work.** For #135 and #137, the approved/frozen #137 landed first; the larger #135 lane then merged canonical `main`, retained its review anchors, and reran every gate. Derive that integration surface from `git diff ..main`, not the other PR's file list — concurrent landed work added an overlap the original two-PR comparison missed. - **Scripted edits (sed/python) in files with repeated similar blocks** (`src/lsp.rs` JSON builders): anchor on a unique line or you will silently edit the wrong block. This produced a vacuously-passing test and cost an hour. - **Acceptance fixtures that open `.rs`/`.py` files** must empty `pmacs.lsp.config` first — the after-load hook spawns real servers (rust/python/c have default configs). Language *detection* (grammars + `pmacs.lsp.filetypes`) is unaffected. - Test scratch buffers have no path ⇒ no language; use tempdir files when language matters. - **Dual-purpose session state is a reset-contract trap** (#120 rounds 2–5): `last_status` doubled as the peer emission baseline AND the stale-diag count freeze, so resetting baselines on `BufferSnapshot` zeroed mid-edit counts. Knowledge about a buffer belongs in shared stores (`DiagnosticStore` severity totals), never in per-session baselines; and any daemon-side reset needs its frontend mirror audited in the same round (the GPU snapshot arm missed search/menu/status the first time). - **Tab width is a rendering semantic, NOT a config gap.** The implementation on `tab-width-parity` fixes the width at the TUI's established 8 columns, shares that constant through `pmacs-protocol`, and expands tabs only in each display projection. Defining `editor.tab-width` could not have fixed the GPU: source text and semantic spans stay byte-addressed while cosmic-text needs projected spaces plus an inverse hit/caret map. A future configurable width would require a buffer-effective frontend fact and cache invalidation; do not re-plan it as a scalar config-only change. - **A test that never runs passes.** Two #127 review-round tests passed vacuously at first: `pmacs.editor.save()` is the RAW save, while `buffer.before-save` fires inside the `buffer.save` COMMAND (`builtin/commands/default.lua`), and `save()` no-ops on an unmodified buffer — so a fixture that opens a file and saves it asserts on bytes nothing rewrote. Dirty the buffer with a real edit and go through `pmacs.command.invoke("buffer.save")`. Caught only because the *other* case failed and the cause was chased instead of the assertion adjusted. - **A message that ALIGNS state cannot be gated on the state it names.** `FrontendEvent::Viewport` both declares a byte range and switches the frontend's window to the buffer it names. Gating the vterm v19 dual declaration on "is the DECLARED buffer a terminal" therefore left a stale in-flight document viewport free to drag a frontend straight back off a terminal a command had just opened — the window oscillated, the terminal declaration was refused every time, and no frame ever arrived. Nothing errored. The gate has to key on the authenticated source's ACTIVE buffer. Generalizes: when two messages declare competing views of "what am I showing", the arbiter is the daemon's own state, never the claim inside either message. - **A pass that sets a mode flag must clear it on EVERY exit.** The semantic producer's terminal pass returned early via `?` when no declaration existed, leaving `terminal_active` set — and the daemon uses that flag to suppress `CursorByte` and the presence sweep, so a frontend that went back to a document silently lost both. Caught by an acceptance assertion, not by any type. - **Sub-crate acceptance needs a real seam, not a fixture.** `pmacs-gpu` depends only on `pmacs-protocol`, so "real daemon + real PTY + real wgpu in one path" could not be an in-crate test. Generalizing `attach::connect`'s reader sink (`connect_with_sink`) and adding `--headless-probe` gave the acceptance the REAL handshake, outbox, writer, and `render_to_view` — which is the whole point; a decoded-message fixture would have proved none of the three fit together. The probe found two real defects the in-process tests did not. - **Real-grid acceptance must budget for macOS startup and path width.** A 100 ms first-Hello timeout failed under loaded macOS CI; use the normal five-second handshake window, then short polling reads. An 80-column split also clipped a custom statusline segment after macOS's long `/var/folders/...` temp path while passing on Linux; size the grid for the longest supported fixture path (the mode-system test uses 160 columns per split). - **A provisional session that fails mid-bootstrap must actually close its socket, not just drop its handle.** #148's dispatcher-side target-failure paths wrote `InitialTargetResult::Failed` and dropped the write-half `UnixStream` clone, but a clone shares the underlying FD — the per-attach reader thread stayed alive with no installed session state. A client that kept the socket open past `Failed` and sent any ordinary event hit an `.expect` reachable only through the new failure path and panicked the whole daemon. Fix: `shutdown(Shutdown::Both)` on every dispatcher-side failure path, plus a defense-in-depth session-registry membership check before any `FrontendEvent` touches render/size/editor state. Generalizes: when a new failure path can leave a handle installed without its owning session, dropping a handle is not the same as tearing down the connection. - **A guard with no production caller passes every direct-call test.** #155 round 1: `EditorCore::try_split_active` implemented the side-window split refusal, but `pmacs.window.split_horizontal` / `split_vertical` — and therefore `C-x 2` / `C-x 3` — still called plain `split_active`. The acceptance test called the core method directly, so reverting the guard entirely would have left every test green. Same shape as folding #142 round 2. Assert through the outermost user-reachable seam (`try_exec(&s, "pmacs.window.split_horizontal()")`), then falsify by revert. When the test shares a file with the code it pins, `scripts/bite` cannot swap it — break the production line by hand and `git checkout --`. - **A geometric readout is not a state predicate.** `TerminalViewStatus::at_bottom` is defined as `scroll_offset == 0` — "the viewport currently reaches the tail", not "this view follows the tail". A still-anchored view satisfies it whenever it happens to be tall enough, so asserting it could not detect that Q#BP7's growth re-arm had never been implemented (#155 round 2): the next rows the child printed pushed the anchored view back into history. Pinning *following* requires advancing the world — feed more child output through a filesystem gate — and asserting the view came along. Related: `scroll_offset` is viewport-relative, so "unchanged across a height change" is vacuous or wrong; the invariant is the frozen ANCHOR. - **A PTY in the default mode does not translate LF to CRLF.** An `echo`-driven test fixture staircases rightward, and past the viewport width every row clips to blanks — so `assert_eq!(top_before, top_after)` compares `"" == ""` and passes for any regression (#155 round 2). Emit `printf '...\r\n'`, and guard text comparisons with `assert!(!observed.is_empty())` the same way the panel daemon pin guards on `!panel_hidden`. - **Widening an ambient resolver into a scoped one can make a total function partial.** #155 round 2 resolved both arms of `pmacs.window.buffer()` through the acting frontend "for uniformity". `acting_frontend` follows the interactive origin, which can name a frontend with no registered view (a bare `dispatch_key` from an unattached peer), so the no-argument arm began raising instead of answering. No runtime caller `pcall`s it, so killring, syntax, autosave, pair, indent and comment silently dropped operations — `kill_ring_acceptance` went 30/30 to 25/5 on every CI platform. The ambient resolver's fallback is what makes it *total*; keep it, and document that as deliberate. Uniformity is not free when the paths have different totality. - **An upgrade decision must be tracked independently of the outcome that triggered it.** #148 published a target's fresh `BufferSnapshot` to existing grid replicas only when the buffer was `newly_loaded || newly_created` — but a target can dedup onto an already-existing, not-yet-CRDT-backed buffer (e.g. one a startup hook created via `find_or_open` and never activated), silently upgrading it without telling pre-attached replicas. The later F29 lazy-upgrade sweep then saw an already-backed buffer and never broadcast it, permanently stranding those replicas on v0.1 round-trip for that buffer. Fix: have the upgrade helper report whether it performed the upgrade, and OR that into the publish decision rather than inferring it from the caller's own load/create branch. ## 6. Named deferrals (the standing backlog, consolidated) **Fixture project-detection census — NOT STARTED, follow-on from R8.** `tests/m4_acceptance.rs` alone constructs state through `EditorState::new_with_roots` **113 times**, and an unknown number of those never call `pmacs.project.set_search_boundary`. Unbounded detection is harmless *only while the assertion does not render a path* — which is why exactly one of them (R8) ever failed, and why the next one will look like a fresh mystery rather than a known class. The work is a census across the suites, not a rewrite: find the unbounded constructions whose assertions are path-sensitive, and bound those. `src/project.rs:208` documents the hazard and `detect_project_within` is the mechanism; eight test files already use it. **Capability-aware keymap resolution — CROSS-CUTTING, NOT STARTED, needs its own framing.** Named here because #220 hit its absence and worked around it, not because any of it is designed. Today `keymap_stack::Scope` is `Buffer | Mode | Global` with **no frontend identity**, and `FrontendEvent` carries no command-invocation variant. Two consequences already paid for: **#220 could ship no default zoom bindings** (`gpu.zoom-in` / `-out` / `-reset` are commands only), and nothing can express "this binding exists only where a GPU is attached". It is genuinely cross-cutting — it touches the keymap stack, the frontend event vocabulary, and what a capability *is* — so it is a framing round before it is a lane. **Do not start it as a half-lane attached to some other stage's branch**, which is how it would arrive by accident; the workaround (commands without bindings) is stable and costs nothing while it waits. Editing: word kills (`M-d`/`M-BS` — need bytes-returning deleters + prepend-on-backward append), `C-SPC` set-mark, `C-u C-y` / `C-M-w`, kill-ring browser + persistence, clipboard watching, block comments + mid-line comment spans, comment-dwim append-at-EOL, per-language comment padding. Pairing (framing "Deferred"): wrap-region on opener, pair-aware backspace, RET-inside-pair closer-on-own-line, in-string/in-comment inhibit (needs node-at-byte `pmacs.parse`), undo amalgamation (pair = one step), balance-aware quotes (the per-buffer toggle SHIPPED in #127 as `editing.auto-pair`). Editops deferrals (full list in its framing): recenter (blocked on viewport facts — the GPU never consumes daemon `view_top`), Unicode case/word classes, region-spanning move/duplicate, locale collation for sort-lines, ensure-final-newline on save. Substrate: buffer-aware edit epoch (after-edit currently compares the ACTIVE buffer only), wire provenance for CRDT self-insert classification, Lua intercept probe, completion.lua still on the old cursor-delta heuristic (migrate to `this_command`), the TUI's nonempty-selection optimistic type-over gate, generated-buffer search invalidation, cross-peer chronological undo arbitration (mixed source/daemon history; pinned by auto-pairing acceptance), origin-pinned `buffer.after-edit` fan-out (a context-switching intercept changes what later callbacks — LSP, completion — observe). LSP/persistence: hidden-buffer LSP attach, daemon desktop-restore, the *warning* half of external-change detection (verify-visited-file- modtime). Config registry (SHIPPED #127; these are its own named deferrals): persistence of settings and the `custom-file` split-brain question, `M-x list-settings` as a listview panel, a settings completion source for the minibuffer (`minibuffer.read`'s `source` is a fixed Rust-side vocabulary), table-valued settings (so `pmacs.lsp.config`, `pmacs.pair.sets`, `pmacs.comment.strings` and the `pmacs.parse.*` write-through proxies stay raw Lua), migrating the remaining scalar setters (`async_config` ×2, `killring.max`, the `enable` booleans) and `pmacs.gpu.set_font`, pending-set staging for names defined after `init.lua` runs, and a `scope = "global"` define flag — `set_local` is currently accepted for `autosave.interval-ms`, where a per-buffer value is meaningless. **Tab width is NOT a config gap** — see §5. Mode system (SHIPPED #129): minor modes, `buffer.after-mode-change`, mode-scoped settings, `describe-mode`, and persistence of explicit major-mode overrides/clears across sessions. Modeline detection (SHIPPED #132): bounded first/last-line Emacs `-*-` and Vim `ft=`/`filetype=` parsing, explicit-over-inferred precedence, alias normalization, and shared fresh-load language pinning for syntax/highlight/LSP startup. Highlight/detection (from the #114–#118 side-quest + injections #122): ~~locals-query processing~~ **SHIPPED #134**; remaining injection follow-ups now that the engine landed (#122) — `injection.combined` (many matches → one shared parse; PHP-in-HTML, some comment schemes), child-tree incrementality + range-scoped layer rebuild (child layers cold-reparse on every settle today), injectable runtime/Lua-registered languages (v1 resolves only against `BUILTIN_LANGUAGES`), and the next injection *consumers* gated on new grammars — HTML/CSS/GraphQL/SQL (`