Ruling A grants the architecture -- direct vector canvas over ResolvedLayoutIR,
viewport-culled, per-system damage -- and deliberately leaves the toolkit open
for this spike to decide under six recorded criteria. All three prerequisites
are discharged (W1 dd33b34, W2 24f8c80, W3 f639919), so the tranche opens.
The contract's problem is not what to build but how to keep the answer honest.
Six criteria across three candidate stacks is unbounded work with a dozen
places for the verdict to be decided by whoever writes the report. So the
structure is an elimination ladder, cheapest disqualifier first, with every
deciding number pinned before it is measured: the fixture ladder F1-F4 and its
musical-content recipe, the deciding rung, the equivalence band, the tie-break
and its three operationally defined axes, and the oracles -- committed, with
their commit recorded, before any candidate renders against them.
Five review rounds shaped it, and most of what they caught was mine.
Measurement. Timed work must be completed GPU work, not submission, or a
candidate that returns after enqueueing looks fast. One common configuration
across all candidates: offscreen, 1920x1080, identical MSAA and format,
--release --locked, both adapters with the integrated one deciding. Freehand
latency runs from scheduled event injection to completion of the first frame
containing that event, backlog included; timing from renderer pickup would let
a candidate buffer the trace, render late, drop nothing, and report fast update
work while lagging visibly.
Damage. The first draft compared raw PrimitiveIndices, which are positions in
flat arrays -- so a pitch change that preserves primitive count moves geometry
while every vector stays identical, and an inserted accidental renumbers
indices so untouched systems look changed. It is now fingerprints over
dereferenced primitives, unowned included. And byte equality alone lets a full
redraw masquerade as per-system damage, so the oracle is paired with a reuse
assertion over the scene cache, at every engraving-valid rung, before the
ranking round rather than inside it.
Outcomes. A check that ran and got the wrong answer is FAIL, not NOT RUN;
conflating them let a broken implementation buy an escalation instead of
recording negative evidence. Capability and timing are separate cells.
Eligibility is a disqualifying set tracked apart from criterion cells, so a
user waiver actually reaches the tie-break instead of leaving a decision with
no effect. Both no-winner paths are total: disqualification, and ranking-loss
wipeout when nobody renders the deciding rung.
Maintenance inputs are reproducible rather than selectable: upstreams pinned
per candidate before any figure is fetched, composites taking the worse value
per axis, maintainer identity machine-observable, the issue snapshot archived,
and unanswered issues contributing infinity rather than their current age --
which would otherwise score twenty ignored issues opened yesterday as
excellent responsiveness.
What the spike is not: the app. No command registry, no editing, no document
layer, no goldens. Ruling D creates epiphany-editor-app fresh after this
verdict. And it does not reopen Ruling A -- a finding that no candidate can
implement the granted architecture escalates as an amendment request and does
not silently promote the SVG path back.
Docs only; no code, no crate, no gate movement.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RSX4zSLgKvtiXaPjnMqLGz
Levi Neuwirth