Repomix is an MIT-licensed CLI (npm, Homebrew, Docker) that packs an entire repository into a single AI-friendly file for feeding to LLMs. Facts below verified as of 2026-09-13.
Repomix is the default answer to “how do I give the model my whole repo”, and it wins by ignoring retrieval entirely, which is a legitimate engineering strategy that context-engine vendors keep pretending is not one.
What it is #
One command, one file, four formats.
repomix emits XML (default, aligned with Anthropic’s XML-tag guidance), Markdown, JSON, or plain text, git-aware through .gitignore, with per-file and total token counts (o200k_base default) and a --token-budget flag that fails CI when the pack exceeds a limit.
Security is built in: Secretlint scans for credential patterns and excludes matching files.
--compress runs tree-sitter extraction of signatures and structure (experimental, vendor-claims about 70% token reduction), and --include-logs/--include-diffs add git history.
Remote packing takes any GitHub URL, branch, or commit, with remote repo configs untrusted by default, and an MCP server mode (also experimental) exposes pack, read, and grep tools with a sandbox flag confining it to a workspace root.
It also generates Claude agent skills and Claude Code plugins, runs in watch mode, and has Chrome, Firefox, and community VSCode extensions plus a web UI at repomix.com.
It is built by Kazuki Yamada (yamadashy), sponsored by Warp and CodeRabbit.
Status #
Active and quietly massive. 28k stars (28,315), 1.5k forks, and 4,517 commits on GitHub, plus 314,271 npm downloads in the last month (2026-08-13 to 2026-09-11), stars, forks, and downloads as of 2026-09-13, with v1.18.0 released 2026-08-08. It was nominated in the Powered by AI category at the JSNation Open Source Awards 2025. The community footprint is the interesting signal: it inverts the usual pattern, with enormous usage but near-zero discourse (the largest HN story I found has 4 points), because a tool that just works generates no threads. A clone ecosystem (Gitingest for Python, Unify, Scribe) confirms the pattern is durable rather than incidental.
Strengths #
- Zero-config and deterministic: no index, no server, no drift between what you see and what the model sees.
- The
grep_repomix_outputMCP tool turns the pack into a searchable corpus, quietly giving agents incremental retrieval over the snapshot without a vector store. - Token counting with a hard
--token-budgetexit code is a genuine CI-grade guardrail most fancier pipelines lack. - Secret scanning before packing addresses the most common whole-repo leak path.
Cautions #
- Whole-repo packing spends context linearly: everything lands in the window, including the middle regions where long-context attention is weakest, so quality degrades as repos grow.
--compressis labeled experimental by its own docs, is lossy by design (drops implementations), and defaults to off.- Freshness is snapshot-time; every edit invalidates the pack (watch mode mitigates locally).
- The imitator crowd is thin forks; adopting a lesser-known clone trades the maintained core for nothing measurable.
Pricing #
Free tool, metered consequence: the pack’s token count is the entire cost model, and the tool hands you the meter. MIT-licensed and free; the real price is the tokens the packed file consumes, which the tool itself counts and can budget.
Compared to #
- Aider: tree-sitter repo maps rank what fits a budget, retrieval-first where Repomix is inclusion-first.
- Sourcegraph code context platform: indexed cross-repo navigation for agents with an enterprise price; Repomix covers the same need for free until scale breaks it.
- Augment Code: sells retrieval as a service inside a platform; Repomix is the static, inspectable alternative that costs nothing to try.
Bottom line #
Recommended for one-shot whole-repo questions in chat UIs, onboarding packs, and CI guards on context budgets, especially for repos under a few hundred thousand tokens. Not for iterative editing of large monorepos, where packing wastes most of the window. My disagreeable claim: for small and mid repos, a Repomix pack plus a good model beats most bespoke RAG pipelines on both quality and setup cost, and teams buying context engines before measuring the dumb approach are optimizing aesthetics, not results.
Changes #
- 2026-08-24 - Created in the Context engines category seed.
See also #
- Tree-sitter code chunking - the parser behind both Repomix’s compression and fancier chunking strategies
- Semantic code search in coding tools - the indexed-retrieval path this tool deliberately skips
- Augment Code - what paying for retrieval instead looks like
- Aider - the budgeted repo map as the middle ground
References #
https://repomix.com/ - feature overview, output formats, awards nomination, sponsors
https://github.com/yamadashy/repomix - stars, commits, CLI reference including –token-budget, –mcp –sandbox, watch mode
https://api.npmjs.org/downloads/point/last-month/repomix - 314,271 downloads for 2026-08-13 to 2026-09-11
https://repomix.com/guide/code-compress - tree-sitter compression semantics and its experimental status
https://repomix.com/guide/mcp-server - MCP tools (pack_codebase, grep_repomix_output) and sandbox confinement
https://news.ycombinator.com/item?id=42028494 - representative HN footprint: 4 points, zero comments