# Gate 3 increment 3 loader/runtime decision report

Date: 2026-08-15
Exact base: `2c2b38b501f94af46ffac3a772f7bf9475154dc5`
Exact implementation/evidence head: `e2e120c211adf3ec9a7909a401f5e7a34f17984f`
Delivery head: the containing documentation commit, resolved with
`git rev-parse HEAD`
Canonical merge: `c1b34503ddd3cb797e5d70671c47afcabfe73832` (PR #103,
rebase merged)
Status: PASS; exact-head audit, rebase merge, and canonical post-merge CI
complete

## Results

| Gate | Result |
|---|---|
| Focused decision contracts | 228 passed in 18.08s; 0 failures |
| Mandatory CPU matrix | Python 3.10: 1,832 passed in 157.58s; Python 3.11: 1,832 passed in 111.93s; Python 3.12: 1,830 passed, 2 expected xfails in 61.09s; 9 conditional deselections on each interpreter |
| Repository coverage | 76.26% statements / 62.67% branches before; 76.60% / 63.25% after |
| Mature CPU scope | 92.87% statements / 82.24% branches before; 93.12% / 82.60% after |
| Changed executable lines | 77/77 (100%) against the exact base |
| Touched production modules | 3/3 pass exact-base line and branch no-regression |
| Runtime decision seam | `runtime_contracts.py`: 100% statements and 100% branches (95 statements, 50 branches) |
| Loader | 91.15% statements / 88.71% branches before; 92.14% / 90.00% after |
| Abliteration runtime | 50.22% statements / 37.38% branches before; 50.82% / 38.03% after |
| Selective mutation | 1,424/1,637 killed (86.99%); 208 survived; 5 timed out; 0 no-test, suspicious, interrupted, or segfault results |
| Mutation runtime | 910.99s; 878,908 KiB maximum parent RSS; required-target guard passed |
| Repeatability | 431 tests passed in each of three file orders/hash seeds; 35.735s total; no flake candidates or consistent failures |
| Package | sdist and wheel built; metadata, contents, isolated import, version, module entry point, and console entry point passed |
| Supply chain | Lock, all-extras import, Gitleaks, Python 3.10–3.12 vulnerability audits, bound CycloneDX SBOM, and license policy passed |

The mandatory Python lanes remain below the 240-second policy budget. The
Python 3.12 wall-clock test time improved from the exact-base 62.73s to 61.09s
while adding three mandatory tests. The slowest focused test was the explicit
4-bit quantization configuration contract at 1.91s.

## Contracts added

1. `ModelLoadPolicy` and `resolve_model_load_policy` define one precedence
   contract for dtype selection, native quantization, bitsandbytes modes,
   device-map behavior, and post-load device movement. Conflicting or unsupported
   combinations fail with exact diagnostic contracts rather than silently
   changing execution mode.
2. `attention_projection_names` defines shared-KV ownership: ordinary layouts
   return all projections, output-only mode returns output projections, the
   shared owner projects all eligible weights, borrowers omit shared K/V and
   K-normalization weights, and impossible ownership layouts fail closed.
3. `is_quantized_parameter` and `classify_weight_storage` distinguish packed
   modules, quantized parameters, integer storage, and floating storage before
   dequantization or replacement. Tests protect float/integer/packed read paths,
   safe packed failures, repacker use, and compatibility temporary-directory
   cleanup.
4. Loader and abliteration execution now consume the pure decision seams. The
   tests assert propagation into the production wrappers, not only helper return
   values.
5. The first exact-SHA mutation campaign exposed eight new seam survivors: one
   diagnostic gap, six killable shared-KV boundary/message gaps, and one
   logically redundant layer-count condition. The repair added the missing
   boundaries and exact errors and removed the redundant condition. The repaired
   full campaign has zero survivors in `runtime_contracts.py`.
6. `runtime_contracts.py` is now a required mutation target. A fresh exact-head
   campaign generated 1,637 mutants, passed the required-target guard, and
   exceeded the immutable 85% score floor without no-test results.

## Verification and evidence

- Python 3.12 coverage/JUnit/trend/repeat evidence:
  `/tmp/obliteratus-gate3-item3-final-py312-98XhzU/`
- Python 3.10 and 3.11 coverage/JUnit/trend evidence:
  `/tmp/obliteratus-gate3-item3-matrix-oKcE2R/`
- Exact-head mutation evidence:
  `/tmp/obliteratus-gate3-item3-repair-mutation-PV8ArC/quality-evidence/`
- Package evidence:
  `/tmp/obliteratus-gate3-item3-package-Z22lEz/`
- Supply-chain evidence:
  `/tmp/obliteratus-gate3-item3-supply-uzr6r7/`

The canonical Ruff F gate, checksum-verified `actionlint`, `uv lock --check`,
conditional-policy validation, risk-map validation, changed-line gate,
touched-module gate, immutable coverage policy, normalized duration policy,
repeat gate, mutation score, and supply-chain decisions all pass. The worktree
was clean before this documentation update.

## Scope and release decision

This increment implements Gate 3 bounded delivery item 3. It does not reopen
ordinary feature work: items 4–7, conditional-evidence reconciliation, and the
final canonical Gate 3 publication remain open. It changes deterministic CPU
decision logic and its wrappers only; CUDA, bitsandbytes hardware execution,
MPS, MLX, network, download, remote, and operator-UI mappings are unchanged, so
no new environment support claim is made.

PR #103 passed its exact-head audit and all required hosted checks with no
unresolved review thread, then rebase merged at
`c1b34503ddd3cb797e5d70671c47afcabfe73832`. All seven jobs in canonical
post-merge run
https://github.com/elder-plinius/OBLITERATUS/actions/runs/31920984688 passed
before item 4 began.
