---
title: Bootstrap command
description: Link local packages and install dependencies in the workspace.
---
> ## Documentation Index
> Fetch the complete documentation index at: https://melos.invertase.dev/llms.txt
> Use this file to discover all available pages before exploring further.

<Info>Supports all [Melos filtering](/filters) flags.</Info>

This command initializes the workspace and installs remaining package
dependencies.

```bash
melos bootstrap
# or

melos bs
```

Bootstrapping has three primary functions:

1. Installing all package dependencies (internally using `pub get`).
2. Syncing shared dependencies between packages.
3. Running any bootstrap lifecycle scripts.

## Why is bootstrapping required?

After Dart 3.6.0 introduced [Pub workspaces](https://dart.dev/tools/pub/workspaces),
`melos bootstrap` is no longer strictly required, because Pub already links
workspace packages. Running `melos bootstrap` is still useful when you want
shared dependencies or custom setup scripts on the bootstrap hooks.

### Benefits

Why use a Melos monorepo?

- All local packages can link to local directories rather than remote ones,
  without modifying the `pubspec.yaml` file.
  - **Example:** Package `A` depends on package `B`, and both exist in the
    monorepo. If you run `pub get` inside package `A`, `pub` retrieves package
    `B` from pub.dev because it does not treat `B` as local. With Melos and Pub
    workspaces, package `B` resolves to a relative path in the repository.
  - Path dependency overrides in package `A` can point at package `B`, but you
    would add and remove them by hand for every publish or commit. That does not
    scale. [FlutterFire](https://github.com/FirebaseExtended/flutterfire) has
    over 40 packages with nested local links (run `melos list --graph` to see
    its graph). Cycles make this worse: package `C` depends on `B`, and `C`
    also depends on `A`.
- Interlinking surfaces Dart analyzer issues early.
  - **Example:** Package `A` relies on package `B` in the same monorepo. Package
    `B` gets a minor API change. After `pub get` on package `A`, the Dart
    analyzer and IDEs report no issues because `pub get` installed `B` from
    pub.dev (not the unpublished local copy). With Melos, packages use local
    versions, so the analyzer and IDEs flag the break and any non-breaking
    deprecations.
- Interlinking lets you work on new, unpublished, or private packages without
  dependency overrides.

## Combine with filters

Bootstrap supports all package filtering options. To bootstrap only a subset of
your packages:

```bash
# Only bootstrap packages that have
# changed since the main branch.

melos bootstrap --diff="main"
```

## Bootstrap flags

- `--no-example` excludes Flutter package example dependencies
  (see [dart-lang/pub#3856](https://github.com/dart-lang/pub/pull/3856)).
  - Runs `pub get` with the `--no-example` flag.
- `--enforce-lockfile` enforces versions from `.lock` files.
  - Check `.lock` files into the repository, or the command may fail.
- `--no-enforce-lockfile` ignores versions from `.lock` files when
  `enforce-lockfile` is set in the root `pubspec.yaml` file.
- `--offline` resolves dependencies from the local cache only by running
  `pub get` with the `--offline` flag.
- `--no-pub` skips `pub get`. Bootstrap still applies shared dependencies,
  dependency overrides, and IDE files. Use this when you want to update the
  workspace `pubspec.yaml` files without resolving dependencies yet.

In addition to these flags, `melos bootstrap` supports configurations in your
root `pubspec.yaml` file.

### Shared dependencies

To share dependency versions across packages in your Melos project, add those
dependencies to the bootstrap config in your root `pubspec.yaml` file.

Bootstrap keeps a root `environment`, `dependencies`, or `dev_dependencies`
entry in sync when that entry also exists in a package. It updates that package
entry to match the bootstrap config each time you run `melos bootstrap`.

For example, a root bootstrap config can look like this:

```yaml
# root pubspec.yaml
# ...

melos:
  command:
    bootstrap:
      environment:
        sdk: ">=3.0.0 <4.0.0"
        flutter: ">=3.0.0 <4.0.0"
      dependencies:
        collection: ^1.18.0
        integral_isolates: any
        uni_links2:
        uni_links_macos:
          git: https://github.com/example/uni_links_macos.git

      dev_dependencies:
        build_runner: ^2.3.3
# ...

```

Because bootstrap overwrites synced versions each run, you may want shared
entries to stand out in package files. When
[`markSharedDependencies`](/configuration/overview#markshareddependencies) is
enabled, Melos marks every shared entry in package `pubspec.yaml` files with a
comment:

```yaml
# packages/my_package/pubspec.yaml

dependencies:
  collection: ^1.18.0 # Managed by Melos, change it in the bootstrap config of the root pubspec.yaml
  path: ^1.9.0
```

## Add a post-bootstrap lifecycle script

Melos supports command [lifecycle hooks](/configuration/scripts#hooks) in your
root `pubspec.yaml` file.

To run a build runner automatically after `melos bootstrap`, add a `post` hook
script:

```yaml
# root pubspec.yaml
# ...

melos:
  command:
    bootstrap:
      hooks:
        post: dart pub run build_runner build
# ...

```

A `post` hook helps meet local project requirements, such as generating files,
when anyone works on the monorepo, including external contributors.