This package provides a simple way for typesetting grammars in Backus-Naur form (BNF). The included bnf environment parses BNF expressions (possibly annotated), so users can write readable BNF expressions in their documents. It features a flexible configuration system, allowing for the customization of the domain-specific language (DSL) used in typesetting the grammar. Additionally, the package comes with sensible defaults. The package requires expl3, xparse, mathtools, and tabularray..