Heavyweight four-track iteration:
- Track A: DEBUG instrumentation sweep (carried four iterations)
- Track G: PGO-disabled Firefox-fourier rebuild
- Track B: mpv libplacebo --vo=gpu segfault investigation
- Track E: multi-context libva safety (Sonnet review 9.6)
Natural sequence: A first (clean codebase), G in parallel on boltzmann
(~2h rebuild offloaded), E next (architectural on clean source), B last
(consumer-side investigation on post-A+E driver).
Phase 4 will subdivide into 4A/4G/4E/4B sub-phases. Phase 5 sonnet
review + Phase 7 verify span all four tracks.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
DEBUG sweep (A) is the carried-four-iterations backlog and natural
prerequisite for upstreaming. mpv libplacebo segfault (B) and perf
binding cell (C) are also long-deferred carryovers. New candidates
this iteration: PGO-disabled Firefox rebuild (G), and the natural
codec/hardware extensions (H).
Recommended primary: A + F (sweep + upstream prep) — with Track A
fixed in iter4, the fork is upstreamable in shape and just needs the
diagnostic noise removed. F is gated on explicit operator instruction
per feedback_no_upstream.md.
Phase 1 lock awaits user candidate pick.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>