> ## Documentation Index
> Fetch the complete documentation index at: https://jncpkg.org/llms.txt
> Use this file to discover all available pages before exploring further.

# jnc update

> Update dependencies in the lock file.

# jnc update

Checks if there are newer versions of dependencies and updates the `jnc.lock` file and environments accordingly. Only updates packages to versions still compatible with the version constraints defined in the manifest.

If no packages are specified, all packages are updated. You can scope updates to specific environments and platforms.

## Usage

```bash theme={null}
jnc update [OPTIONS] [PACKAGES]...
```

## Arguments

| Argument        | Description                                                                              |
| --------------- | ---------------------------------------------------------------------------------------- |
| `[PACKAGES]...` | The packages to update, space-separated. If none are provided, all packages are updated. |

## Options

| Option                  | Short | Description                                                                                                   |
| ----------------------- | ----- | ------------------------------------------------------------------------------------------------------------- |
| `--environment <ENV>`   | `-e`  | The environments to update. Can be specified multiple times. If none are given, all environments are updated. |
| `--platform <PLATFORM>` | `-p`  | The platforms to update. Can be specified multiple times. If none are given, all platforms are updated.       |
| `--dry-run`             | `-n`  | Show what would be updated without writing changes to the lock file or environment.                           |
| `--json`                |       | Output the changes in JSON format.                                                                            |
| `--no-install`          |       | Update the lock file without installing the environment.                                                      |

## Global Options

| Option                   | Short | Description                                    |
| ------------------------ | ----- | ---------------------------------------------- |
| `--manifest-path <PATH>` | `-m`  | Path to `jnc.toml` or the workspace directory. |

## Examples

Update all packages:

```bash theme={null}
jnc update
```

Update specific packages:

```bash theme={null}
jnc update python numpy
```

Update only in a specific environment:

```bash theme={null}
jnc update --environment test
```

Preview changes without applying them:

```bash theme={null}
jnc update --dry-run
```

Update for a specific platform:

```bash theme={null}
jnc update --platform linux-aarch64
```

Output changes as JSON:

```bash theme={null}
jnc update --json
```