v0.5.0

A faster, more accurate re-ranker.

laya-code-r2 is the new default re-ranker.

• It is a ModernBERT-base model with laya's decision head, trained by this project on laya-codex's own candidate lists. It replaces laya-code-r1.
• It is served at 128 tokens × 12 candidates, for prompts and for search.
• More right files: offline, it inlines 141 of 238 gold files, against r1's 132 and keywords' 118.
• Faster prompt hook: about 130 ms (p50, M4 Pro) instead of 517 ms, with four exact Metal speed-ups of the forward pass. Their output is bit-identical.
• Smaller download: about 330 MB instead of 850 MB.

Metal on macOS before 15. candle 0.11 panicked when it opened a Metal device on macOS 14 and earlier. Every release since v0.1.0 therefore ranked by keywords only on those Macs. Fixed.

Benchmark v15: 60 held-out tasks, Claude Sonnet 5.5.

per session	stock	v0.4.0	v0.5.0
Cost	$0.066	$0.062	$0.062 (−6.6% vs stock)
Wall-clock	21.8 s	18.1 s	18.5 s (−15.2%)
Lookup calls	3.87	2.03	1.83
Lookup time	10.6 s	6.4 s	5.4 s
Right files, first question	0.73	0.81	0.84

• Against v0.4.0: lookup time −16.7%. Cost and recall moved the right way but not significantly, and nothing got worse.
• Against stock: code read plus injected is +32%.
• Caveat: the run's score cache was off because of a full disk, which adds hook time only. See docs/RESULTS.md.

Upgrade

• An r1 install keeps working.
• Get r2 with curl -fsSL https://raw.githubusercontent.com/pilotspace/laya-codex/main/install.sh | sh -s -- --model-only.
• laya-codex doctor shows which model is serving.

Full list: CHANGELOG.