# Lockfile

> Bun's lockfile format and configuration

`bun install` creates a lockfile called `bun.lock`.

#### Should it be committed to git?

Yes

#### Generate a lockfile without installing?

To generate a lockfile without installing to `node_modules`, use the `--lockfile-only` flag. Bun always saves the lockfile to disk, even if it is already up to date with your project's `package.json`(s). The exception is when `--frozen-lockfile` (or `--production`) is set.

```bash terminal icon="terminal"
bun install --lockfile-only
```

`bun add`, `bun remove`, and `bun update` also accept `--lockfile-only`.

<Note>
  `--lockfile-only` still populates the global install cache with registry metadata and git/tarball dependencies.
</Note>

#### Can I opt out?

To install without creating a lockfile:

```bash terminal icon="terminal"
bun install --no-save
```

To write a Yarn lockfile _in addition_ to `bun.lock`:

<CodeGroup>

```bash terminal icon="terminal"
bun install --yarn
```

```toml bunfig.toml icon="settings"
[install.lockfile]
# whether to save a non-Bun lockfile alongside bun.lock
# only "yarn" is supported
print = "yarn"
```

</CodeGroup>

#### Text-based lockfile

Bun v1.2 changed the default lockfile format to the text-based `bun.lock`. To migrate an existing binary `bun.lockb`, run `bun install --save-text-lockfile --frozen-lockfile --lockfile-only` and delete `bun.lockb`.

For more on the format, see [the blog post](https://bun.com/blog/bun-lock-text-lockfile).

#### Automatic lockfile migration

When you run `bun install` in a project without a `bun.lock`, Bun automatically migrates existing lockfiles:

- `yarn.lock` (v1)
- `package-lock.json` (npm, `lockfileVersion` 2, 3 or 4)
- `pnpm-lock.yaml` (pnpm)

Bun does not migrate a `package-lock.json` from npm 6 or older (`lockfileVersion` 1); it prints a warning and resolves from `package.json` instead.

Bun preserves the original lockfile. You can remove it manually after verification.