This repository provides a Claude Code skill for literate programming, along with supporting CLI tools. The skill (SKILL.md) defines a slash command that transforms a codebase into a `.lit.md` file – a single Markdown document that weaves prose, diagrams, and named code chunks together. The actual tools are three TypeScript scripts: `tangle.ts` extracts source files from a `.lit.md`, `untangle.ts` reverse-syncs edits back into the `.lit.md`, and `hook-reverse-sync.ts` is a Claude Code PostToolUse hook for automatic reverse-sync. The architecture is simple: standalone scripts with no external dependencies beyond Bun's runtime. The tangler parses fenced code blocks with `{chunk="name" file="path"}` attributes, builds a dictionary of chunks (supporting additive chunks), and recursively expands `<<reference>>` with cycle detection and indent preservation. The untangler uses a `.lit.map.json` source map to splice edited lines back into the original `.lit.md`, then re-tangles. The code is clean, well-documented, and demonstrates good engineering practices for a small tool. It is not a data research project nor a typical application – it is a developer tool for literate programming workflows.