# 01 — Lock the safetensors-versus-GGUF performance contract

Status: ready-for-agent

## Mandatory fresh-session context

- Read [RALPH-CONTEXT.md](../RALPH-CONTEXT.md) completely before changing code.
- This issue is `DGR-001` in [prd.json](../prd.json).
- Read the evidence README for every dependency listed below.
- Inspect current code and `git status`; historical text and previous agent claims are not evidence.

## Description

As a runtime engineer, I need a controlled baseline so that GGUF work proceeds from measured speed, memory, and quality rather than reputation.

## Expected durable outputs

- Benchmark harness and deterministic tests
- evidence/DGR-001/performance-contract.json
- Raw and summarized safetensors/GGUF benchmark evidence

## Acceptance criteria

- [ ] Benchmark the same model architecture/revision, machine, prompts, context lengths, output lengths, sampling policy, and concurrency across the current Transformers/safetensors recipe and whole-model llama.cpp recipes.
- [ ] Separate correctness/quality lanes from quantized performance/fit lanes instead of claiming BF16 and Q4 are numerically equivalent.
- [ ] Report TTFT, prefill tok/s, decode tok/s, p50/p95 latency, aggregate throughput, RSS, VRAM, artifact size, failures, and output drift in machine-readable JSON.
- [ ] Add concurrency levels 1 and 4 where memory permits.
- [ ] Write a versioned performance contract consumed by later release gates, including an explicit stop condition when llama.cpp/GGUF has no meaningful speed or fit benefit.
- [ ] Targeted pytest tests pass
- [ ] python -m compileall packages tests passes for Python changes
- [ ] git diff --check passes
- [ ] Default tests remain deterministic, model-download-free, API-credit-free, and GPU-free
- [ ] Full deterministic pytest -q passes, or the exact pre-existing unrelated failure is recorded with a clean-tree reproduction
- [ ] Real-model execution is opt-in through MESHNET_ENABLE_REAL_INFERENCE_TESTS=1 and records exact artifact/runtime/hardware evidence
- [ ] Model artifacts remain on the configured mounted-drive storage and never under /home
- [ ] Read .scratch/distributed-gguf-runtime/RALPH-CONTEXT.md and this story issue completely before changing code
- [ ] Read and verify every dependency evidence README before relying on dependency behavior
- [ ] Preserve all pre-existing working-tree changes and stage only files belonging to this story
- [ ] Write .scratch/distributed-gguf-runtime/evidence/DGR-001/README.md with files changed, exact commands and real results, limitations, compatibility notes, and dependent-story handoff
- [ ] Update only this story issue to Status: done after every acceptance criterion and quality gate passes

## Dependency handoff

- None. This story may start immediately.

## Finish contract

- Create the task evidence directory and durable handoff required above.
- Preserve real failures and blockers; never fabricate benchmark, model, test or hardware output.
- Change this issue to `Status: done` only after all criteria pass.
- Emit `<promise>COMPLETE</promise>` only after the evidence handoff exists.

## References

- [Ralph execution context](../RALPH-CONTEXT.md)
- [PRD](../PRD.md)
- [Implementation strategy](../implementation-strategy.md)
- [Current architecture](../architecture.md)
- [Architecture decision](../ADR-0020-distributed-gguf-runtime.md)
