understand-codebase

Use ast-grep (sg) for syntax-aware pattern matching to locate function definitions and calls, combined with rg for fast text searches across files. This finds symbol definitions and their usage points throughout the repository structure.

Yes. Use sg to map call flows by finding where functions are defined and invoked, then use rg to locate imports and dependencies. This reveals how components interact and traces execution paths through the system.

Start with fd to discover file structure and entry points, then use sg for AST-level pattern searches to find class definitions and relationships, and rg to locate imports and cross-module dependencies. This builds a map of how the system is organized.

Yes. Both rg and sg support multiple languages. sg provides syntax-aware searching across language-specific AST patterns, while rg handles text-based searches uniformly, allowing codebase navigation regardless of the languages used.

Use rg for fast text search to find all occurrences of the symbol name, then use sg for precise AST-based queries to distinguish definitions from usages. This pinpoints exact locations in files and reveals call relationships.

While rg and sg are fast, extremely large codebases may require refined search patterns to reduce noise. AST-grep patterns must match the target language's syntax, and broad text searches can return many results—narrowing queries by file type or directory scope improves precision.