Launching today
BlazeDiff Agent
Visual regression your coding agent runs
3 followers
Visual regression your coding agent runs
3 followers
BlazeDiff Agent auto-discovers your routes, captures deterministic screenshots, and runs pixel diffs locally. It hands a small region tile to Claude Code, Cursor, or Codex for a verdict, instead of you eyeballing 40 full-size PNGs. No SaaS. No API key. MIT. Built on N-API (Rust), WASM, and pure-JS diff cores: 3 to 4× faster than odiff, 8× faster than pixelmatch on 4K. Already used by Vitest, Shopify, Ant Design, Vega, and ApexCharts.
Hi everyone, Tim here. Quick story on why I made this.
A few years back, my team had visual tests running in Cypress. They worked, but were slow enough that running them stopped being routine. We moved to a SaaS to fix that: a bit faster, nicer UI, more knobs. But the bill climbed, screenshots left our infra, and we still spent time going through dozens of diffs manually.
I started with the speed part. Wrote a pure-JS pixel-diff faster than pixelmatch, then a Rust+SIMD version via N-API, then a WASM build for browsers. The native binary is now ~3-4x faster than odiff and ~8x pixelmatch on 4K. About half a year in, Vitest, Shopify, and the Ant Group ecosystem ended up pulling BlazeDiff core in.
Next painful part: ambiguous diffs. The tool is local-first, so the question was how to solve this on every engineer's machine. Coding agents have become standard on most teams, so I can just wire it in there.
BlazeDiff Agent uses the same heuristic interpreter I built for CI, crops the diff into small region tiles, and runs a second-pass LLM analysis on just those tiles. It returns a text verdict: regression, intentional, or noise. If the change is a padding shift, it tells you to update the baseline and move on, no clicking. No SaaS, no API key, screenshots never leave the box, MIT.
Two things I'd love feedback on:
1. Does the agent handoff feel like the right primitive, or would you want it fully automated?
2. Anything that would stop you from trying it on your CI today?
Quickstart: `npx @blazediff/agent onboard`.
Repo: https://github.com/teimurjan/blazediff
Around all day, happy to dig into specifics.