Patch dependencies – Package manager

bun patch lets you persistently patch node_modules in a maintainable, git-friendly way.

Sometimes, you need to make a small change to a package in node_modules/ to fix a bug or add a feature. bun patch makes it easy to do this without vendoring the entire package and reuse the patch across multiple installs, multiple projects, and multiple machines.

Features:

Generates .patch files applied to dependencies in node_modules on install
.patch files can be committed to your repository, reused across multiple installs, projects, and machines
"patchedDependencies" in package.json keeps track of patched packages
bun patch lets you patch packages in node_modules/ while preserving the integrity of Bun's Global Cache
Test your changes locally before committing them with bun patch --commit <pkg>
To preserve disk space and keep bun install fast, patched packages are committed to the Global Cache and shared across projects where possible

Step 1. Prepare the package for patching

To get started, use bun patch <pkg> to prepare the package for patching:

# you can supply the package name
bun patch react

# ...and a precise version in case multiple versions are installed
bun patch react@17.0.2

# or the path to the package
bun patch node_modules/react

Note — Don't forget to call bun patch <pkg>! This ensures the package folder in node_modules/ contains a fresh copy of the package with no symlinks/hardlinks to Bun's cache.

If you forget to do this, you might end up editing the package globally in the cache!

Step 2. Test your changes locally

bun patch <pkg> makes it safe to edit the <pkg> in node_modules/ directly, while preserving the integrity of Bun's Global Cache. This works by re-creating an unlinked clone of the package in node_modules/ and diffing it against the original package in the Global Cache.

Step 3. Commit your changes

Once you're happy with your changes, run bun patch --commit <path or pkg>.

Bun will generate a patch file in patches/, update your package.json and lockfile, and Bun will start using the patched package:

# you can supply the path to the patched package
bun patch --commit node_modules/react

# ... or the package name and optionally the version
bun patch --commit react@17.0.2

# choose the directory to store the patch files
bun patch --commit react --patches-dir=mypatches

# `patch-commit` is available for compatibility with pnpm
bun patch-commit react

CLI Usage

$bun patch <package>@<version> flags or options

Flags

Configuration

-c,--config=<val>

Specify path to config file (bunfig.toml)

--registry=<val>

Use a specific registry by default, overriding .npmrc, bunfig.toml and environment variables

Dependency Management

-y,--yarn

Write a yarn.lock file (yarn v1)

-p,--production

Don't install devDependencies

--no-save

Don't update package.json or save a lockfile

--save

Save to package.json (true by default)

--omit=<val>

Exclude 'dev', 'optional', or 'peer' dependencies from install

Lockfile Management

--frozen-lockfile

Disallow changes to lockfile

--save-text-lockfile

Save a text-based lockfile

--lockfile-only

Generate a lockfile without installing dependencies

Installation Behavior

-f,--force

Always request the latest versions from the registry & reinstall all dependencies

--dry-run

Don't install anything

--ignore-scripts

Skip lifecycle scripts in the project's package.json (dependency scripts are never run)

--trust

Add to trustedDependencies in the project's package.json and install the package(s)

Caching and Performance

--cache-dir=<val>

Store & load cached data from a specific directory path

--no-cache

Ignore manifest cache entirely

--concurrent-scripts=<val>

Maximum number of concurrent jobs for lifecycle scripts (default 5)

--network-concurrency=<val>

Maximum number of concurrent network requests (default 48)

--backend=<val>

Platform-specific optimizations for installing dependencies. Possible values: "clonefile" (default), "hardlink", "symlink", "copyfile"

Logging and Output

--silent

Don't log anything

--verbose

Excessively verbose logging

--no-progress

Disable the progress bar

--no-summary

Don't print a summary

Security and Verification

--ca=<val>

Provide a Certificate Authority signing certificate

--cafile=<val>

The same as `--ca`, but is a file path to the certificate

--no-verify

Skip verifying integrity of newly downloaded packages

Utility

-g,--global

Install globally

--cwd=<val>

Set a specific cwd

-h,--help

Print this help menu

Patching

--commit

Install a package containing modifications in `dir`

--patches-dir=<val>

The directory to put the patch file in (only if --commit is used)