docs/research/2026-06-29-best-in-slot-local-coder.md

Best-in-slot local coder — the grounding gate (2026-06-29)

Loop stage: Reason (model selection) + Verify (no unproven lead). Status: decided + implemented. LoopCoder-v2 registered behind an evidence gate.

Question

Are we using LoopCoder, and is there a more optimal local coder for Keystone's 8GB box than the current Qwen2.5-Coder-7B lever?

Findings (claim · evidence · confidence · source)

  • We were not using LoopCoder. The local chain is Ouro-1.4B (Σ₀-native,

rank-order kernel lead) + Qwen2.5-Coder-7B (capability-first lever, 8GB) + Qwen-3.6-27B (≥24GB frontier), cloud-first Claude for real coding. Confidence: high. Source: apps/lantern-garage/lib/local-model-registry.js.

  • LoopCoder-v2 is a real, attractive candidate. 7B Parallel-Loop-Transformer,

Apache-2.0, 131K ctx, looped architecture (Σ₀-aligned in spirit). Reported SWE-bench Verified 64.4 (two-loop) vs 43.0 one-loop baseline; ">2 loops regress." Confidence: medium — every number is vendor-reported, not reproduced. Sources: arXiv:2606.18023, HF model card.

  • It is NOT yet deployable here. Custom IQuestPLTCoderForCausalLM arch with

no documented GGUF/Ollama path (model card references a vLLM fork), tool-calling undocumented, and experiments/loopcoder_v2_4bit_probe.py (already in-repo) has never rundata/convergence/loopcoder-probe-log.jsonl does not exist. Confidence: high. Source: repo state, model card.

  • GLM-5.2 is not a looped model and not local. 753B/40B MoE + IndexShare sparse

attention, MIT — a strong cloud coder, irrelevant to the 8GB local slot. Do not classify it as recurrent-depth. Confidence: high. Source: The AI Rankings.

Decision

Keep Ouro as the Σ₀-native default. Register LoopCoder-v2 as a coding candidate gated by a new verified flag: a model whose capability is vendor-claimed but not reproduced on our hardware (verified:false) is sorted behind every reproduced peer and can never auto-lead a benchmark we haven't run (External Reality Rule). It enters the registry without displacing the known-good Qwen lead.

Promotion path: run python experiments/loopcoder_v2_4bit_probe.py on thebox (FIT/RUNS/SPEED → data/convergence/loopcoder-probe-log.jsonl), then — if it loads 4-bit and produces coherent code — drive eval_humaneval_chat.py / the SWE harness to reproduce the capability number, set capabilityScore from the measured result, and flip verified:true. LOCAL_ALLOW_UNVERIFIED=1 lifts the gate so that probe/eval run can actually lead the candidate.

What this does NOT claim

We have not run LoopCoder-v2. The 64.4 figure is unverified vendor data. This change only makes the candidate registerable without risk and encodes the rule that on-box evidence — not a vendor benchmark — is what promotes a model to lead.