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Who published Poly Lint Format?

kreuzberg-dev (@kreuzberg-dev) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Poly Lint Format by kreuzberg-dev — Agent Skill

Name: Poly Lint Format
Author: kreuzberg-dev

Poly Lint Format

Reference for poly, the single-binary multi-language linter and formatter — per-language engines, the lint/fmt commands, poly.toml configuration, severity behavior, and the shared CI validation workflow. Load when linting or formatting code, configuring poly.toml, or wiring poly into CI.

File contents

Poly

Poly is a single-binary multi-language linter and formatter. It bundles language engines (ruff for Python, oxc for JS/TS/JSON, taplo for TOML, rumdl for Markdown) and delegates to native tools (cargo fmt, cargo clippy, golangci-lint, actionlint, shellcheck, shfmt) when present. Most repos need no extra toolchains. Configure via per-repo poly.toml.

Engines by language

Scope	Engine(s)
Python	ruff (lint + format), pyrefly (type check)
JS/TS/JSON/CSS	oxc (lint + format)
TOML	taplo (lint + format)
Markdown	rumdl (format)
Rust	cargo fmt + cargo clippy (via cargo hook)
Go	golangci-lint
Java	checkstyle, maven verify
Ruby	rubocop (format + lint)
C#	dotnet format
PHP	php-cs-fixer, phpstan
Elixir	mix format, mix credo
R	styler, lintr
C/C++	clang-format, cppcheck
Shell	shfmt, shellcheck
Git	gitfluff (commit message linting), ai-rulez-generate
GH Actions	actionlint
Helm/K8s	helm-lint, kubeconform

Commands

Lint: poly lint .
Check formatting (dry-run): poly fmt --check .
Apply formatting: poly fmt --fix .
Apply lint autofixes: poly lint --fix .

Configuration

Per-repo poly.toml defines linting and formatting rules:

[discovery] — exclude globs
[lint.<lang>.<tool>] — select/ignore rules, settings like pydocstyle_convention, line_length
[per-file-ignores] — file-specific exemptions
[fmt.<lang>.<tool>] — formatter options
[hooks.builtin] — git hook configuration

Cache directory .polylint/ is gitignored.

Severity

poly lint exits non-zero only on error-severity findings. Warnings are reported but do not fail CI.

CI

Run linting and formatting validation in CI via the shared reusable workflow:

uses: xberg-io/actions/.github/workflows/reusable-validate.yml@v1

This workflow runs poly fmt --check . then poly lint . with optional inputs setup-rust and setup-python.

Always run poly fmt --check . and poly lint . after making changes to verify compliance.

---name: poly-lint-formatdescription: Reference for poly, the single-binary multi-language linter and formatter — per-language engines, the lint/fmt commands, poly.toml configuration, severity behavior, and the shared CI validation workflow. Load when linting or formatting code, configuring poly.toml, or wiring poly into CI.---# PolyPoly is a single-binary multi-language linter and formatter. It bundles language engines (ruff for Python, oxc for JS/TS/JSON, taplo for TOML, rumdl for Markdown) and delegates to native tools (cargo fmt, cargo clippy, golangci-lint, actionlint, shellcheck, shfmt) when present. Most repos need no extra toolchains. Configure via per-repo `poly.toml`.## Engines by language| Scope | Engine(s) ||-------|-----------|| **Python** | ruff (lint + format), pyrefly (type check) || **JS/TS/JSON/CSS** | oxc (lint + format) || **TOML** | taplo (lint + format) || **Markdown** | rumdl (format) || **Rust** | cargo fmt + cargo clippy (via cargo hook) || **Go** | golangci-lint || **Java** | checkstyle, maven verify || **Ruby** | rubocop (format + lint) || **C#** | dotnet format || **PHP** | php-cs-fixer, phpstan || **Elixir** | mix format, mix credo || **R** | styler, lintr || **C/C++** | clang-format, cppcheck || **Shell** | shfmt, shellcheck || **Git** | gitfluff (commit message linting), ai-rulez-generate || **GH Actions** | actionlint || **Helm/K8s** | helm-lint, kubeconform |## Commands- Lint: `poly lint .`- Check formatting (dry-run): `poly fmt --check .`- Apply formatting: `poly fmt --fix .`- Apply lint autofixes: `poly lint --fix .`## ConfigurationPer-repo `poly.toml` defines linting and formatting rules:- `[discovery]` — exclude globs- `[lint.<lang>.<tool>]` — select/ignore rules, settings like `pydocstyle_convention`, `line_length`- `[per-file-ignores]` — file-specific exemptions- `[fmt.<lang>.<tool>]` — formatter options- `[hooks.builtin]` — git hook configurationCache directory `.polylint/` is gitignored.## Severity`poly lint` exits non-zero only on error-severity findings. Warnings are reported but do not fail CI.## CIRun linting and formatting validation in CI via the shared reusable workflow:```yamluses: xberg-io/actions/.github/workflows/reusable-validate.yml@v1```This workflow runs `poly fmt --check .` then `poly lint .` with optional inputs `setup-rust` and `setup-python`.Always run `poly fmt --check .` and `poly lint .` after making changes to verify compliance.

Frequently asked questions