Fast on real repositories
Django: 3,113 files in 0.82s. home-assistant: 25,443 files in 3.5s. Cold cache, on Apple Silicon — a blake3 content hash skips unchanged work and rayon splits the rest across cores.
One binary lints and formats the whole repository
Curated Rust backends for the languages that matter, a tree-sitter tier for everything else, and one poly.toml driving lint, format, git hooks and commit policy. No Node, no Python, no Ruby, no JVM.
poly wraps ruff, oxc, biome, mago, taplo, rumdl, sqruff, malva, markup_fmt, rubyfmt and more as
in-process Rust crates — not subprocesses — and falls through to a tree-sitter generic tier for
the long tail. Two cross-cutting lint tiers, a code-quality metrics engine and a 26-rule built-in
ast-grep pack, run on top of every language.
What you get
Section titled “What you get”No toolchain to install
Most backends are Rust crates compiled into the binary. rustfmt, gofmt and shellcheck
are used when found on PATH; everything else is opt-in. A missing tool lowers fidelity,
never fails a run.
One config file
poly.toml drives linting, formatting, git hooks and commit-message policy. Nested configs
cascade in a monorepo; extends shares a baseline across repositories.
Built for agents
A Claude/Codex plugin and a stdio MCP server ship in the box. An agent calls poly’s eleven tools directly instead of shelling out and parsing terminal text.
Git hooks without a framework
poly hooks install wires lint, format, file-safety and Conventional-Commit checks into
git. Hooks validate a snapshot of the index, never the live worktree.
Honest coverage accounting
Every skipped file is counted with its reason, so a run that checked nothing can never look
like a clean pass. --deny-skips turns that into a CI gate.
Install
Section titled “Install”curl -fsSL https://raw.githubusercontent.com/Goldziher/poly/main/install.sh | shirm https://raw.githubusercontent.com/Goldziher/poly/main/install.ps1 | iexbrew install Goldziher/tap/polyscoop bucket add goldziher https://github.com/Goldziher/scoop-bucketscoop install polynpm install --global @goldziher/polylintpip install polylint/plugin marketplace add Goldziher/poly/plugin install poly@polyExplore
Section titled “Explore”IntroductionWhat poly is, how the tiers fit together, and when to reach for it.
QuickstartLint, format, and wire the git hooks in about a minute.
Configurationpoly.toml end to end: rule selection, suppression, monorepos, quality metrics.
Git hooksThe native hook runner: stages, staged isolation, timeouts, concurrency, caching.
Agents and MCPThe plugin, the eleven MCP tools, and the async whole-project tasks.
CLI referenceEvery flag, every subcommand, and the exit-code contract.
Backend coverageWhich backend handles which language, and at which tier.
Tool catalogAll 348 opt-in catalog tools across 175 languages.