2026-04-27 - Phi-4-mini Four-Layer Fused Shard Golden Passed

Intent: Run the next quality gate after the layers [0,4) Phi-4-mini 4-layer fused shard passed strict ANE residency, following the validation-first notes validation-before-scale and whole-operation fusion discipline.

Setup: Ran the range golden validator --layer-start 0 --layer-end 4 --mlmodelc local artifacts --json-out temporary output; no cleanup/deletion and no energy benchmark.

Result: PASS=True. Range golden smoke for [0,4) passed with cos_hidden=0.999597, rmse_hidden=0.020061, and max_abs_hidden=0.269531. The first 4-layer fused Phi-4-mini shard now passes both strict ANE residency and numerical smoke.

Surprise / hurdle: The 4-layer fused shard preserved numerical agreement after already proving full ANE residency despite its larger compiled size.

Lesson: A single successful 4-layer fused shard is promising, but 4-layer fusion needs representative or full-range validation before runtime migration.

Next: Validate representative or all 4-layer ranges before migrating the runtime; do not run energy benchmarking until residency and quality gates hold across that broader set.

Refs: research/ANE_CHAIN_SCHEMA.md