# Catalogs (/pm/catalogs)

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Related: [bunx](/pm/bunx.md), [Workspaces](/pm/workspaces.md), [bun --filter](/pm/filter.md), [Global cache](/pm/global-cache.md), [Global virtual store](/pm/global-store.md), [Isolated installs](/pm/isolated-installs.md)

**Catalogs** share dependency versions across the packages in a monorepo. Rather than repeating the same versions in each workspace package, you define them once in the root `package.json` and reference them throughout your project.

## Overview [#overview]

Instead of each workspace package specifying its own versions, you:

1. Define version catalogs in the root `package.json`
2. Reference those versions with the `catalog:` protocol
3. Update every package at once by changing the version in one place

Catalogs matter most in large monorepos where dozens of packages depend on the same versions of key dependencies.

## How to Use Catalogs [#how-to-use-catalogs]

### Directory Structure Example [#directory-structure-example]

Consider a monorepo with the following structure:

```
my-monorepo/
├── package.json
├── bun.lock
└── packages/
    ├── app/
    │   └── package.json
    ├── ui/
    │   └── package.json
    └── utils/
        └── package.json
```

### 1. Define Catalogs in Root package.json [#1-define-catalogs-in-root-packagejson]

In your root-level `package.json`, add a `catalog` or `catalogs` field within the `workspaces` object:

```json icon="file-json" title="package.json"
{
  "name": "my-monorepo",
  "workspaces": {
    "packages": ["packages/*"],
    "catalog": {
      "react": "^19.0.0",
      "react-dom": "^19.0.0"
    },
    "catalogs": {
      "testing": {
        "jest": "30.0.0",
        "testing-library": "14.0.0"
      }
    }
  }
}
```

`catalog` and `catalogs` also work at the top level of `package.json`.

### 2. Reference Catalog Versions in Workspace Packages [#2-reference-catalog-versions-in-workspace-packages]

In your workspace packages, use the `catalog:` protocol to reference versions:

```json icon="file-json" title="packages/app/package.json"
{
  "name": "app",
  "dependencies": {
    "react": "catalog:",
    "react-dom": "catalog:",
    "jest": "catalog:testing"
  }
}
```

```json icon="file-json" title="packages/ui/package.json"
{
  "name": "ui",
  "dependencies": {
    "react": "catalog:",
    "react-dom": "catalog:"
  },
  "devDependencies": {
    "jest": "catalog:testing",
    "testing-library": "catalog:testing"
  },
  "peerDependencies": {
    "react": "catalog:"
  }
}
```

`catalog:` references work in `dependencies`, `devDependencies`, `optionalDependencies`, `peerDependencies`, and as the value of a root [`overrides`](/pm/overrides) rule. A catalog reference behaves exactly as if the catalog's range were written inline.

### 3. Run Bun Install [#3-run-bun-install]

Run `bun install` to install all dependencies according to the catalog versions.

## Catalog vs Catalogs [#catalog-vs-catalogs]

Bun supports two ways to define catalogs:

1. **`catalog`** (singular): A single default catalog for commonly used dependencies

   ```json icon="file-json" title="package.json"
   "catalog": {
     "react": "^19.0.0",
     "react-dom": "^19.0.0"
   }
   ```

   Reference with `catalog:`:

   ```json icon="file-json" title="packages/app/package.json"
   "dependencies": {
     "react": "catalog:"
   }
   ```

2. **`catalogs`** (plural): Multiple named catalogs for grouping dependencies

   ```json icon="file-json" title="package.json"
   "catalogs": {
     "testing": {
       "jest": "30.0.0"
     },
     "ui": {
       "tailwind": "4.0.0"
     }
   }
   ```

   Reference with `catalog:<name>`:

   ```json icon="file-json" title="packages/app/package.json"
   "dependencies": {
     "jest": "catalog:testing",
     "tailwind": "catalog:ui"
   }
   ```

## Benefits of Using Catalogs [#benefits-of-using-catalogs]

* **Consistency**: All packages use the same version of critical dependencies
* **Maintenance**: Update a dependency version in one place instead of across multiple `package.json` files
* **Clarity**: Makes it obvious which dependencies are standardized across your monorepo
* **Simplicity**: No extra version resolution strategies or external tools

## Real-World Example [#real-world-example]

A larger example, for a React application:

**Root package.json**

```json icon="file-json" title="package.json"
{
  "name": "react-monorepo",
  "workspaces": {
    "packages": ["packages/*"],
    "catalog": {
      "react": "^19.0.0",
      "react-dom": "^19.0.0",
      "react-router-dom": "^6.15.0"
    },
    "catalogs": {
      "build": {
        "webpack": "5.88.2",
        "babel": "7.22.10"
      },
      "testing": {
        "jest": "29.6.2",
        "react-testing-library": "14.0.0"
      }
    }
  },
  "devDependencies": {
    "typescript": "5.1.6"
  }
}
```

```json icon="file-json" title="packages/app/package.json"
{
  "name": "app",
  "dependencies": {
    "react": "catalog:",
    "react-dom": "catalog:",
    "react-router-dom": "catalog:",
    "@monorepo/ui": "workspace:*",
    "@monorepo/utils": "workspace:*"
  },
  "devDependencies": {
    "webpack": "catalog:build",
    "babel": "catalog:build",
    "jest": "catalog:testing",
    "react-testing-library": "catalog:testing"
  }
}
```

```json icon="file-json" title="packages/ui/package.json"
{
  "name": "@monorepo/ui",
  "dependencies": {
    "react": "catalog:",
    "react-dom": "catalog:"
  },
  "devDependencies": {
    "jest": "catalog:testing",
    "react-testing-library": "catalog:testing"
  }
}
```

```json icon="file-json" title="packages/utils/package.json"
{
  "name": "@monorepo/utils",
  "dependencies": {
    "react": "catalog:"
  },
  "devDependencies": {
    "jest": "catalog:testing"
  }
}
```

## Updating Versions [#updating-versions]

To update versions across all packages, change the version in the root package.json:

```json icon="file-json" title="package.json"
"catalog": {
  "react": "^19.1.0",  // Updated from ^19.0.0
  "react-dom": "^19.1.0"  // Updated from ^19.0.0
}
```

Then run `bun install` to update all packages.

## Adding to the catalog with `bun add` [#adding-to-the-catalog-with-bun-add]

`bun add --catalog` adds the entry to the root catalog and writes `"catalog:"` to the current package; `--catalog=<name>` adds it to `catalogs.<name>` and writes `"catalog:<name>"`. Bun reuses an existing catalog entry unless you pass an explicit version. See [`bun add --catalog`](/pm/cli/add#--catalog).

```bash icon="terminal" title="terminal" terminal
bun add react --catalog
```

Even without the flag, `bun add react` (no version) writes `"catalog:"` when the default catalog already lists `react`. Pass a version to write a concrete range instead.

## Lockfile Integration [#lockfile-integration]

Bun's lockfile tracks catalog versions, so installs are consistent across environments. The lockfile includes:

* The catalog definitions from your package.json
* The resolution of each cataloged dependency

```json icon="file-json" title="bun.lock(excerpt)"
{
  "lockfileVersion": 2,
  "workspaces": {
    "": {
      "name": "react-monorepo",
    },
    "packages/app": {
      "name": "app",
      "dependencies": {
        "react": "catalog:",
        "react-dom": "catalog:",
        ...
      },
    },
    ...
  },
  "catalog": {
    "react": "^19.0.0",
    "react-dom": "^19.0.0",
    ...
  },
  "catalogs": {
    "build": {
      "webpack": "5.88.2",
      ...
    },
    ...
  },
  "packages": {
    ...
  }
}
```

## Limitations and Edge Cases [#limitations-and-edge-cases]

* Catalog references must match a dependency defined in either `catalog` or one of the named `catalogs`
* Bun ignores empty strings and whitespace in catalog names and treats them as the default catalog
* `catalog:default` is the same as `catalog:`. You can define the default catalog as either `catalog` or `catalogs.default`, but a package listed in both is an error
* Invalid dependency versions in catalogs fail to resolve during `bun install`
* `catalog:` only works in the root and workspace `package.json` files. Inside a published package it fails to resolve. Publish with `bun publish` or `bun pm pack`, which replace it with the real range (see [Publishing](#publishing))

## Publishing [#publishing]

When you run `bun publish` or `bun pm pack`, Bun replaces `catalog:` references
in your `package.json` with the resolved version numbers. The published package
includes regular semver strings and no longer depends on your catalog
definitions.