mlxsmith 0.1.2

Apple Silicon MLX fine-tuning toolkit — SFT, DPO/ORPO, GRPO, distillation, and OpenAI-compatible serving.

mlxsmith

Apple Silicon MLX fine-tuning toolkit — SFT, DPO/ORPO, GRPO, distillation, and OpenAI-compatible serving.

Status: alpha (v0.1.2). Full training pipeline validated on Qwen3-4B.

Install

MLX training and serving require macOS on Apple Silicon. Other platforms can use data tools and mock backends.

python -m venv .venv && source .venv/bin/activate
pip install -U pip

# Core CLI (data tools, config, project scaffolding)
pip install mlxsmith

# Apple Silicon training + serving
pip install "mlxsmith[mlx,llm,serve]"

# Everything
pip install "mlxsmith[all]"

Quickstart

mlxsmith init myproj
cd myproj
mlxsmith doctor        # check Python, MLX, Metal

Training

SFT (LoRA/QLoRA)

mlxsmith sft --model cache/mlx/Qwen__Qwen3-4B-Instruct-2507 --data data/sft

Produces run artifacts under runs/sft_NNNN/ (adapter weights, metrics.jsonl, config snapshot).

Preference tuning (DPO/ORPO)

mlxsmith pref --model cache/mlx/Qwen__Qwen3-4B-Instruct-2507 \
  --data data/prefs --algo dpo

Supports DPO and ORPO algorithms with configurable beta and KL coefficients. Expects {prompt, chosen, rejected} data format.

Reinforced fine-tuning (GRPO)

mlxsmith rft --model cache/mlx/Qwen__Qwen3-4B-Instruct-2507 \
  --env envs/coding.yaml --verifier verifiers/pytest.py

GRPO-style RL training with token-level environment integration and verifier-based rewards. Rollout acceptance/rejection gating with reward tracking.

Knowledge distillation

# Offline distillation (teacher generates, student learns)
mlxsmith distill --teacher large-model --student small-model --mode offline

# Online preference distillation (OPD)
mlxsmith distill --teacher large-model --student small-model --mode opd

Full pipeline

# Run SFT → Pref → RFT in sequence
mlxsmith pipeline

Serving

OpenAI-compatible /v1/chat/completions endpoint.

mlxsmith serve --model runs/sft_0001/adapter --port 8080

curl http://localhost:8080/v1/chat/completions \
  -H 'Content-Type: application/json' \
  -d '{"messages":[{"role":"user","content":"Hello"}],"max_tokens":64}'

Supports streaming ("stream": true), logprobs, stop sequences, and an optional UI dashboard (serve.ui: true in config).

Data tools

mlxsmith data presets                                     # list built-in datasets
mlxsmith data pull alpaca                                 # pull a preset
mlxsmith data import raw.json --out data/sft/train.jsonl  # import ShareGPT → JSONL
mlxsmith data split data/sft/train.jsonl --fractions 0.9 0.05 0.05
mlxsmith data stats data/sft/train.jsonl                  # token counts, field analysis
mlxsmith data validate data/sft/train.jsonl               # structure check

Built-in presets: alpaca, hh-rlhf, ultrachat-200k, ultrafeedback-binarized-prefs, ultrafeedback-binarized-sft.

Model management

# Pull + convert HF model to MLX
mlxsmith pull Qwen/Qwen3-4B-Instruct-2507

# With quantization
mlxsmith pull Qwen/Qwen3-4B-Instruct-2507 --quantize --q-bits 4

# Merge adapters
mlxsmith adapters merge runs/sft_0001/adapter runs/pref_0001/adapter --weights 0.7 0.3

HF auth

mlxsmith auth login --token "$HF_TOKEN"
mlxsmith auth status
mlxsmith auth logout

Eval and bench

# Evaluation suite (pass@k with verifier checks)
mlxsmith eval --suite eval/suites/coding.yaml

# Benchmark inference or training throughput
mlxsmith bench --mode inference
mlxsmith bench --mode trainer
mlxsmith bench --mode end_to_end

Verifiers

Built-in verifiers for eval, RFT, and preference tuning:

• regex — pattern matching on completions
• jsonschema — JSON structure validation
• pytest — sandboxed test execution
• docker — containerized verification
• compose — multi-verifier composition (AND/OR/weighted)

See docs/VERIFIERS.md for the verifier API.

Environment plugin system

mlxsmith env list                  # list available environments
mlxsmith env info envs/coding.yaml # show manifest (tasks, verifier, version)
mlxsmith env init my_env           # scaffold a new environment
mlxsmith env install ./my_env      # install from directory
mlxsmith env package ./my_env      # create distributable tarball
mlxsmith env run envs/coding.yaml  # execute RFT with this environment

Environments define tasks, verifiers, and reward functions for RFT training. See docs/ENVIRONMENTS.md.

Config system

mlxsmith config show              # display merged config (YAML/JSON/TOML)
mlxsmith config show --sources    # show where each value comes from
mlxsmith config init              # create default mlxsmith.yaml
mlxsmith config validate          # check config structure
mlxsmith config env               # show environment variable mapping

Config sources (in priority order): CLI flags > environment variables (MLXSMITH__SECTION__KEY) > config file > defaults.

SDK (programmatic API)

For building custom training loops:

from mlxsmith.sdk import load_model, SamplingClient, TrainingClient, TrainingBatch

loaded = load_model("path/to/model", config)

# Sampling with logprobs
sampler = SamplingClient(loaded.backend)
result = sampler.sample("prompt", logprobs_k=5)

# Training operations
trainer = TrainingClient(loaded.backend)
trainer.create_optimizer(lr=1e-4, weight_decay=0.01)
fb = trainer.forward_backward(batch)
trainer.optim_step(fb.result().grads)

Loss functions: DPO, ORPO, GRPO, CISPO, DRO, PPO, importance sampling, cross-entropy.

Research

RLM self-play loop

RLM (Recursive Language Model) is a research feature — the infrastructure runs but has not produced measured gains yet.

mlxsmith rlm                       # single-process RLM
mlxsmith pipeline --orchestrated   # multi-process orchestrated RLM
mlxsmith rlm status                # check iteration state
mlxsmith rlm history               # view history

Includes task generation, mutation for data diversity, corpus management, EMA-based gating, and weight pointer IPC for multi-process coordination. See docs/orchestrator.md.

Docs

• docs/PROJECT_FORMAT.md — project layout and artifacts
• docs/VERIFIERS.md — verifier API and sandbox behavior
• docs/COMPATIBILITY.md — tested versions and model families
• docs/ENVIRONMENTS.md — environment plugin system
• docs/orchestrator.md — multi-process RLM orchestrator
• docs/rlm-ctl.md — RLM training guide
• docs/ROADMAP.md — product direction and milestones
• docs/README.md — full docs index

License

MIT