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opensrc

opensrc

github.com/vercel-labsDevelopment3.0k3.0k installsUpdated 6w ago
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About opensrc

opensrc is a command-line tool for fetching dependency source code so developers and coding agents can inspect implementations beyond their types. It resolves npm versions from project lockfiles, supports package and repository references, and caches fetched source globally.

Key features

  1. 01Fetch package and repository source
  2. 02Resolve npm versions from lockfiles
  3. 03Pin repository branches, tags, or commits
  4. 04Cache sources globally
  5. 05List, remove, and clean cached sources

Use cases

  1. 01Inspecting a dependency's internal behavior
  2. 02Debugging unexpected library behavior
  3. 03Finding edge-case handling in tests
  4. 04Learning implementation patterns from source

Install

Copy the command and run it in a terminal.

$npx skills add https://github.com/vercel-labs/opensrc --skill opensrc

After installing, type/opensrcin Claude Code to confirm it loaded.

Details

From the project README

Source Code Fetching with opensrc

Fetches dependency source code so agents can read implementations, not just types. Clones repositories at the correct version tag and caches them globally at ~/.opensrc/.

Core Pattern

rg "parse" $(opensrc path zod)
cat $(opensrc path zod)/src/types.ts
find $(opensrc path zod) -name "*.test.ts"

opensrc path <pkg> prints the absolute path to cached source. If not cached, it fetches automatically. Progress goes to stderr, path to stdout, so $(opensrc path ...) works in subshells.

Fetching Source Code

opensrc path zod
opensrc path pypi:requests
opensrc path crates:serde
opensrc path facebook/react

# Multiple packages at once
opensrc path zod react next
opensrc path pypi:requests pypi:flask
opensrc path crates:serde crates:tokio

# Specific versions
opensrc path [email protected]
opensrc path pypi:[email protected]
opensrc path owner/[email protected]
opensrc path owner/repo#main
Version Resolution

For npm packages, opensrc auto-detects the installed version from lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock). Use --cwd to resolve from a different project:

opensrc path zod --cwd /path/to/project

For PyPI and crates.io, explicit versions or latest are used. For repos, use @ref or #ref to pin a branch, tag, or commit.

Managing the Cache

Source is cached globally at ~/.opensrc/ (override with OPENSRC_HOME).

opensrc list                     # show all cached sources
opensrc list --json              # JSON output

opensrc remove zod               # remove a package
opensrc remove facebook/react    # remove a repo

opensrc clean                    # remove everything
opensrc clean --npm              # only npm packages
opensrc clean --pypi             # only PyPI packages
opensrc clean --crates           # only crates.io packages
opensrc clean --packages         # all packages, keep repos
opensrc clean --repos            # all repos, keep packages

When to Fetch Source

Fetch source when you need to:

  • Understand internal behavior that types don't reveal
  • Debug unexpected library behavior
  • Learn patterns from well-known implementations
  • Verify how a function handles edge cases

Don't fetch source for simple API usage questions that docs or types can answer.

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