Ask HN: Has anyone replaced Claude/GPT with a local model for daily coding?

Many developers are experimenting with replacing cloud AI coding assistants like Claude and GPT with local open-weight models such as Qwen 3.6 and Gemma 4, often running on high‑VRAM GPUs or large‑RAM Macs. They report that local models can be “good enough” for personal projects, privacy‑sensitive work, and well‑scoped tasks—especially when paired with strong agentic harnesses like Pi or OpenCode—but still fall short of frontier models for complex, large‑repo or highly autonomous coding. A recurring theme is that hardware cost, electricity, setup complexity and weaker tooling often outweigh subscription fees, while cheap API access to powerful non‑US models (e.g. DeepSeek, Kimi, GLM) currently offers the most practical middle ground.

Overall sentiment

  • Very few people have fully replaced Claude/GPT with local models for daily coding.
  • Many use a hybrid: local open‑weights for most work, frontier models (Claude/GPT/DeepSeek/Kimi/GLM) for planning, hard bugs, or reviews.
  • Consensus: local is “good and getting better,” but still generally behind top cloud models for reliability, reasoning, and large-repo work.

Hardware & performance

  • Useful setups often involve:
    • High‑VRAM GPUs (RTX 3090/4090/6000, 4×5070, Radeon 7900XTX/R9700).
    • High‑RAM Apple silicon (M4/M5/Mac Studio 64–512 GB) or Strix Halo 128 GB.
  • Typical performance reports:
    • ~40–150 tok/s decode, 400–4000 tok/s prefill on ~30–35B models, depending on MTP, quant, and concurrency.
  • Electricity is non‑trivial but usually much cheaper than hardware CAPEX; some back‑of‑the‑envelope TCO shows cloud APIs still cheaper for many users.

Model choices & perceived quality

  • Most‑praised local models for coding:
    • Qwen 3.6 27B dense (often Q4–Q6 quant). Frequently compared to somewhere between Haiku and older Sonnet.
    • Qwen 3.6 35B A3B (MoE) for speed; often a bit worse than 27B dense at coding.
    • Gemma 4 (26–31B, including QAT variants) as a strong general model, sometimes weaker than Qwen at tool‑use.
    • DeepSeek V4 Flash / ds4 on high‑end Apple or GPU rigs for reasoning‑heavy work.
  • Large MoE open models (Qwen 3.5 122B‑A10B, Nemotron, MiniMax) can be strong but require big RAM and are slower; some find them worse than well‑tuned 27B–35B dense.

Harnesses, tooling & workflows

  • Harness quality is seen as at least as important as the model:
    • Popular: pi.dev, Claude Code (pointed at local endpoints), OpenCode, Crush, Aider, custom CLIs, VS Code/Copilot to local llama.cpp servers.
  • Effective patterns:
    • Agentic workflows with strict tools, sub‑agents, or multi‑step plans.
    • Frontier model writes spec/plan; local model implements.
    • Multiple local agents with narrow roles (plan, schema, code, tests, review).

Limitations & pain points

  • Common issues:
    • Loops, over‑thinking, and broken tool/edit calls, especially with aggressive quantization or poor sampling.
    • Context limits and cache quirks; quality drops at long contexts despite large nominal windows.
    • Slowness and fan/noise on laptops; complex repos feel “forever” compared to cloud.
    • Setup complexity: drivers, quant choices, KV cache settings, batching, harness config.
  • Many report local models feel like a capable but junior dev; frontier models feel more like a strong mid/senior, especially for architecture and tricky bugs.

Privacy, cost, and strategy

  • Reasons to go local:
    • Data privacy/compliance, avoiding lock‑in, fear of future price hikes or regulation, enjoyment of tinkering.
    • “Good enough” for personal projects, scripting, glue code, document tasks.
  • Reasons not to:
    • Hardware cost vs heavily subsidized $20–$100/mo frontier subs.
    • Cloud models (esp. DeepSeek/Kimi/GLM) are extremely cheap per token and clearly more capable.
  • Emerging pattern: layered approach—local first, then cheap open‑weights APIs, then frontier only when really needed.