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

# Automatic switching

> Use Jolter shims to switch toolchains without shell hooks or manual version changes.

Jolter switches versions through shims. A shim is a small executable under a command name such as `node`, `pnpm`, `yarn`, `bun`, `deno`, or a plugin command. It resolves the current project and launches the selected real command.

## Install shims

```bash theme={null}
jolter setup
```

The command creates or refreshes shims, checks whether the shims directory is on `PATH`, and prints current-session plus persistent setup commands for your shell.

Supported shell setup targets:

```bash theme={null}
jolter setup --shell powershell
jolter setup --shell cmd
jolter setup --shell bash
jolter setup --shell zsh
jolter setup --shell fish
```

## Shim location

Default paths:

```text theme={null}
Windows: %USERPROFILE%\.jolter\shims
Unix:   $HOME/.jolter/shims
```

With custom storage:

```text theme={null}
$JOLTER_HOME/shims
```

## PATH precedence

The Jolter shims directory must appear before competing executables from system Node.js installations, nvm, fnm, Volta, Corepack, and package-manager-specific global binary directories.

Check command routing:

<CodeGroup>
  ```powershell PowerShell theme={null}
  Get-Command node -All
  Get-Command pnpm -All
  ```

  ```batch Command Prompt theme={null}
  where node
  where pnpm
  ```

  ```bash Bash and Zsh theme={null}
  type -a node
  type -a pnpm
  ```

  ```fish Fish theme={null}
  type -a node
  type -a pnpm
  ```
</CodeGroup>

The first result should be inside Jolter's shims directory.

## What happens at runtime

When a shim runs, Jolter:

1. identifies the invoked command;
2. resolves project requirements from the current directory upward;
3. selects a complete local installation;
4. falls back to the global active version when no project requirement applies;
5. launches the real executable or JavaScript tool entry point.

Shims do not install missing versions. Prepare the project first:

```bash theme={null}
jolter sync
```

## Refresh shims

Run setup again after upgrading or moving Jolter, changing `JOLTER_HOME`, restoring a backup, installing plugins that expose commands, or diagnosing stale shims.

```bash theme={null}
jolter setup
jolter doctor
```

## IDE terminals

IDEs inherit environment variables from the process that launched them. After changing persistent PATH settings, restart the entire IDE, not only its integrated terminal.

GUI applications on macOS and Linux may not read interactive shell profiles. Configure the environment using the mechanism supported by the application or operating system.


## Related topics

- [Mental model](/mental-model.md)
- [Quickstart](/quickstart.md)
- [Jolter](/index.md)
- [Publish a plugin](/plugins/publish-a-plugin.md)