Levi Neuwirth
13c3d2fd46
Kind and tag 34, schema major 3, minor epoch 10. The last rung before G3, and the one that closes P13-S13: the tuning context becomes operation-authored, so it finally has a canonical carrier. The closure argument is the metadata precedent, not the canonical base - the base embeds no graph values for any field, and metadata has been durable purely through its operations since M2d. The payload carries epiphany_core::TuningContextSettings, a five-field subset of ScoreTuningContext, not the full graph type. ScoreTuningContext's codec deliberately drops accidental_extensions, so a full-value payload would have diverged between a live session, where accept stores the envelope as a value, and the same document reloaded, where the field decodes empty. canonical_value! could not have caught that: it compares bytes and never the originating value, so a field that never reached the bytes is structurally invisible to it. The subset makes the divergence unrepresentable instead of relying on a normalization step nothing can enforce, and it costs no wire design - the encoding is byte-identical to the existing five-field walk, which tuning_context_settings_canonical_bytes_match_score_tuning_context asserts directly. Reduction leaves accidental_extensions untouched. SetTuningContext is the sole genesis payload born at major 3, because minimal stamping is a function of each payload's value, so the accept-set raise is charged to this one surface: OperationEnvelopeBlock 2 to 3. The doc comment above it did not merely record the cap, it asserted that no operation payload embeds the tuning context - a sentence this rung falsifies - so it is rewritten rather than left beside a corrected constant. Undo restores the seeded base settings, default or not, and the never-authored versus authored-to-default distinction stays unobservable. An earlier draft of the contract had that backwards; PLAN_GENESIS_OPS section 5 trap 5 withdrew it, and SetMetadata is the disproof. Fixes two undefined references the interrupted run had not yet reached: operation_catalog.tex referenced sec:evolution:major3, a label defined in binary_format.tex, which LaTeX cannot resolve across documents. Replaced with the sectionsc convention already used for every other cross-companion citation in that file. Gate: 1409 tests, clippy 0, fmt clean, conformance 8/8 including [7f], both vector corpora regenerated, all four PDFs at 0 undefined references. The t5 and t7 mutations were re-run independently and observed to fail as specified; the remaining eight are not signed off, because the implementing run was stopped before it reported them. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01QjsEnYhm1gPpf6ii2iFxFV |
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README.md
epiphany-ops
The Epiphany concurrent semantics: the operations through which the score
graph becomes a live model, and the deterministic reduction by which a set of
operations becomes a materialized score state. Implements the normative
requirements of Chapter 6 (Semantic Operations and Concurrent Reduction) of
the core specification (spec/core_spec.pdf). This is Agent C's crate per
spec/QUICKSTART.md, building on Agent A's epiphany-determinism and Agent B's
epiphany-core.
A score's state is defined by the set of operations committed to it. Any materialized graph is a deterministic reduction of that set; caches, snapshots, and partial reductions are acceleration structures, never the source of truth. — Chapter 6, Design Principles
The thesis in one paragraph
The replicated operation set is a grow-only CRDT: replicas accumulate envelopes and converge on the same set. The materialized graph is not a CRDT — it is the deterministic reduction of that set in a single canonical order (causal-first, then the HLC tuple). Any permutation of the same envelopes reduces to byte-identical materialized state. That property is the determinism heart of the architecture, and the reduction fuzzer is its tripwire.
What's here
| Area | Items | Spec |
|---|---|---|
| Stamps | HybridLogicalClock, OperationStamp, the reduction & monotonicity tuples |
Ch. 6 §"Operation Identity and Stamps" |
| Causal context | CausalContext (dotted version vector), covers, the missing-predecessor signal |
Ch. 6 §6.2 |
| Payloads | OperationKind, the discriminator-only OperationKindTag, OperationPayload, the §6.10 representative ops |
Ch. 6 §"Operation Envelopes", §6.10 |
| Envelopes | OperationEnvelope, EnvelopeHash (MUSCENVH), well_formed (incl. stamp.id == id) |
Ch. 6 §6.4 |
| Slots | OperationSlot::{Single, Equivocated}, the order-independent (Pass-10) transitions |
Ch. 6 §6.5 |
| Anomalies | AnomalousReplicaSegment, IntegrityAnomaly/Kind, the HLC-monotonicity detector |
Ch. 6 §6.6; Ch. 5 §"System-Derived Counter Collisions" |
| Effects | OperationEffect, NoOpReason, the typed PreconditionFailureReason, RepairRecord/RepairKind |
Ch. 6 §6.3.2, §6.5 |
| Conflicts | ConflictRecord, ConflictKind, content-derived ConflictId (derive_conflict_id), the registry, resolution |
Ch. 6 §6.4 |
| Transactions / undo | TransactionDescriptor with the causal-prior-descriptor rule, UndoTransactionPayload / UndoPolicy |
Ch. 6 §6.6, §6.8 |
| Operation set | OperationSet: accept pipeline (well-formedness → slot → causal), grow-only |
Ch. 6 §"Envelope Acceptance" |
| Reduction | canonical_reduction_order (single function), MaterializedState, the reduction driver |
Ch. 6 §6.3 |
The determinism this crate enforces
- A single reduction-order function.
canonical_reduction_orderperforms deterministic causal topological ordering, using the intrinsic stamp tuple(physical, logical, replica, counter)only among ready operations. - Order-independent equivocation. A duplicate
OperationIdwith different canonical bytes transitions its slot toEquivocatedregardless of which envelope arrived first (Pass 10). Equivocated slots contribute nothing to reduction; dependents are held pending. - Content-derived facts.
ConflictIdandIntegrityAnomalyIdare derived from content, so two replicas reducing the same set agree on every conflict and anomaly id — the conflict registry and anomaly register are deterministic materialized facts, not local bookkeeping. - Byte-identical materialized state.
MaterializedState::canonical_bytesserializes the effect log, conflict registry, anomaly register, object existence, spellings, and LWW fields in their normative orders. - Real graph materialization.
OperationSet::reduce_onto(&base_score)returnsGraphMaterialization { state, score }. The graph is mutated in the same canonical order and compares by canonical event identity, independent of arena storage order.
Hand-off gates
Run the gate harnesses (QUICKSTART, Agent C):
cargo test -p epiphany-ops
cargo run --release -p epiphany-ops --example fuzz_reduction # 10k iters, seed 0
cargo run --release -p epiphany-ops --example fuzz_reduction 100000 7 # soak, seed 7
- Reduction determinism — every randomized envelope set reduces to byte-identical materialized state under any acceptance order (v0 acceptance criteria 1 and 5).
- Equivocation order-independence — every duplicate-id-with-different-bytes scenario equivocates regardless of arrival order (v0 acceptance criterion 3).
The integration tests (tests/concurrent_reduction.rs) exercise these plus
transaction atomicity, descriptor precedence, anomaly exclusion, and forward
undo through the public API.
Scope and decisions
Chapter 6 specifies the framework and a representative selection of
operations; the full ~60–80-primitive catalog is an explicit open question
(§6.11) deferred to the Operation Catalog companion. This crate implements the
framework in full and the representative operations, which is sufficient to
exercise every reduction discipline. The representative operations can also
reduce onto an epiphany_core::Score: insert/delete, voice promotion, supported
cross-cutting structures, system breaks, migration checks, transaction
rollback, and undo mutate the real graph while preserving Agent B's invariants.
reduce() remains the base-free CRDT/bookkeeping API; reduce_onto() is the
graph-aware editing path. See DECISIONS.md for remaining payload boundaries.
Per QUICKSTART "Don't do these": undo is the spec's forward compensating
operation, never inverse-based; unsafe is forbidden; everything is sync.