FastLint

A polyglot linter that bundles best-in-class open-source checkers — making vibe coding safer and faster.

One command, every file, every language. Rather than reimplementing analyses, FastLint stitches together proven checkers from crates.io behind a single CLI that respects .gitignore and skips binaries automatically.

Install

cargo install fastlint

Run

fastlint                  # check current directory
fastlint source/frontend  # check a path
fastlint --json           # JSON diagnostics

Bundled checks

typos warning

Source-code spell-checking powered by the typos crate.

merge-conflict error

Catches unresolved <<<<<<< / ======= / >>>>>>> markers before they ship.

trailing-whitespace warning

Flags trailing spaces and tabs at the end of any line.

More checkers are being added — see the GitHub repository for the current roster.