39.5 concluded the exact CP-SAT seeder beats greedy (harbor 102 -> 92,
maple 156 -> 154). Re-checked because fdp made the arms deterministic and
3qj made the model 7.5x slower. Three findings.
A live bug in the cap, found on the way. solve_room_labels sets a
deterministic work-unit budget (4.0) and a wall-clock backstop, commented
as "a pathological-case backstop only". At 2.0s it had become THE BINDING
CONSTRAINT: 2 of 24 harbor solves returned FEASIBLE not OPTIMAL, wall time
hit exactly 2010 ms, and the deterministic budget was never reached (max
2.483/4.0). Those labellings were suboptimal AND load-dependent -- the wall
clock is exactly the cap 39.5 added the deterministic one to escape. Cause:
38.14's t -> n adjacency makes the model much harder, and the 2s value
dated from when solves took ~124 ms. Raised to 30s; 24/24 harbor and 36/36
maple now OPTIMAL, deterministic budget still in headroom (3.569/4.0).
The verdict reverses. Deterministic, 12 seeds, scored canonically:
harbor greedy 1323 (722h) 0.079 s/seed cpsat 1548 (908h) 1.623
maple greedy 1764 (777h) 0.063 s/seed cpsat 2256 (1213h) 1.327
cpsat loses on both, +225 and +492 fails at ~21x the seeding time,
concentrated in hard fails.
Time and quality have different causes. Removing t -> n from harbor takes
cpsat 1.623 -> 0.193 s/seed (8.4x faster) but it is still +205 vs greedy
(was +225) -- so the adjacency explains the time blow-up and ~9% of the
quality gap; the regression is otherwise pre-existing.
Squaring with 39.5: that section records cpsat returning 194/180/171/182
over four identical 10-seed aggregates before the determinism work. Its
10-fail harbor margin sits well inside a noise band that wide, and was
measured with fdp's id()-ordered room_slots live. The seeder-level claim
was never established rather than overturned. 39.5 annotated in place.
Absolute totals are ~6x 39.5's because the objective has changed, so they
are not comparable to that table; the within-measurement comparison is
like-for-like and is what the verdict rests on.
No default changes: assign_solver was already greedy for 37.7's independent
reason. What changes is that "cpsat wins the seeder A/B" should no longer
be cited as a reason to pursue it.
The cap fix takes the suite from ~4.5 to ~10 min and the tests cannot opt
out, since constructive_topology does not thread the solver limits through.
Filed as homemaker-py-2xk.
Closes homemaker-py-vjd.
Lint at parity (46); tests 384 passed, 0 failed.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MJ84Feep79Hhm3E4zZJmnB
Answering "are we clean". Generic namespace: yes. Usage namespace: no.
FINISH §39.4. The first sweep missed sites, found by a full re-grep:
graph.py's free-area budget, operators.py host-preference / keep-type /
repair-candidate, fitness.py's ("l","c","k") public-access test, bubble.py's
generic adjacency reference, and -- the important one -- cpsat.py, which was
still matching adjacency by raw startswith. graph.code_matches_requirement is
now the single public answer to "does this leaf count as the thing the
programme asked to be next to", shared by has_adjacency, has_vertical_connection
and cpsat.
RETRACT §39.5. It concluded 2g7.5's CP-SAT seeder win did not survive the
correction. That was wrong. The cause was the missed cpsat matcher above: the
exact solver was optimising a different relation than the scorer checked, so a
failing test reporting an incomplete sweep was misread as a baseline shift.
Re-measured over 6 seeds, cpsat now wins on both programmes (harbor 102/92,
maple 156/154). xfail removed.
REAL BUG UNDERNEATH: CP-SAT was never deterministic despite
num_search_workers=1 and a comment claiming it. neighbors[slot] is a set of
dom.Node, which hashes by id() -- a memory address -- so raw iteration made the
model-build order vary and CP-SAT returned a different equally-optimal
assignment each run (measured 194/180/171/182 over four identical aggregates).
sorted() on the slot indices fixes it. Also paired the wall-clock cap with
max_deterministic_time (solves run ~124ms against a 2s cap, so nothing was
timing out -- latent hazard, not the cause). solve_room_labels is now
reproducible on every captured instance; constructive_topology on the cpsat
path still is not, filed as homemaker-py-fdp (plausible contributor to b8g).
§39.6 THE SECOND NAMESPACE. Usage prefixes b/t/l/k (bedroom/toilet/living/
kitchen) classify programme codes by first letter and stay prefix-based by
design, but they are not inert: has_circulation deletes graph edges from them.
Four corpus rooms are misclassified by spelling -- la1 "Laundry Room" and li1
"Library Corner" as living, br1 "Staff Room" as bedroom, tr1 "Treatment Room"
as toilet. Measured on a health-centre seed: tr1 loses its edge to the adjacent
O, br1 loses its edge to t10 "Staff WC" -- both feed the connectivity fails §38
found persisting. Filed homemaker-py-sel; an explicit usage: key is the fix,
but it changes fitness for correctly-spelled programmes too so it needs its own
A/B.
DOCS. README gains a "Room codes and reserved names" section; CLAUDE.md and
AGENTS.md gain the same summary for agents. audit_programme_config.py now
reports the usage class each code picks up alongside the namespace and
satisfiability checks. DESIGN §37.2's note calling the c/o/s quirk "existing
product behaviour, not a bug" is annotated as superseded.
Corpus audit: zero generic-namespace violations across all ten example
programmes. 346 passed, same 7 pre-existing fixture failures, lint unchanged.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MJ84Feep79Hhm3E4zZJmnB
Adds src/homemaker_layout/cpsat.py (OR-Tools CP-SAT) as an exact alternative
to operators._assign_adjacency_aware's greedy/beam room-code placement,
wired in as assign_solver="greedy"|"cpsat" (EXPERIMENTAL, default "greedy",
byte-identical to before) through constructive_topology/lift_base_to_storeys/
driver.search, plus a new operators.mutate_reassign in-search repair
operator (driver.search's enable_reassign=False default, mirrors
enable_ruin_recreate). Both found and fixed a resize-fragility bug (a
second CP-SAT pass against settled geometry, operators._cpsat_relabel_settled)
and a CP-SAT symmetry-blowup stall (explicit interchangeable-code grouping).
Seeder-level A/B on harbor-house is a solid, low-noise positive (~13% fewer
real fitness-scored secondary-adjacency fails, 10 seeds). Full driver.search
A/B is only pilot-scale (budget=3000 vs the bead's own 20k target) and
inconclusive -- both flags stay default-off pending a larger-N confirmation.
Full writeup: DESIGN.md §37.7. Bead left in_progress (own acceptance
criteria not fully met); homemaker-py-5bv tracks the deferred post-collapse
repair item.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LSwQwpEaHFBkeVSDDWd75S
Claude
