A simple Node.js environment manager.

nen is a small CLI tool for managing Node.js environments. The primary goal of nen is to maintain a small API (small enough for you to remember all of the commands), yet still remain functional enough to provide some benefit.

To create a new Node.js environment, the new command can be used. The name of the environment and the desired Node.js version must be provided to the command.

$ nen new my-node-project -v12

The version number can be

• Just a major version number (e.g. 10 or 13), in which case the latest release of that major version will be used.
• A major version and a minor version (e.g. 10.18, 13.9), in which case the latest release of that minor version will be used.
• A specific version (e.g. 10.18.0, 13.9.2), in which case that specific version will be used.

If the requested version of Node.js has not been used before, it will be downloaded.

Once the appropriate Node.js version is available, a new environment folder will be created in the nen home directory ($NEN_HOME, or $HOME/.nen by default).

This environment folder will contain a bin/ directory which contains symlinks to the appropriate Node.js binaries, and an .npm-global/ folder in which global npm modules for that environment will be stored.

To activate an environment which has been created, the use command can be used. The name of the environment to activate must be provided.

$ nen use my-node-project

When a project is activated, a few things happen:

• Your current $PATH is copied into $NEN_OLD_PATH.
• $NEN_HOME/environments/my-node-project/.npm-global is prepended to your $PATH.
• $NEN_HOME/environments/my-node-project/bin is prepended to your $PATH.
• $NPM_CONFIG_PREFIX is set to $NEN_HOME/environments/my-node-project/.npm-global.
• $NEN_ENV is set to the name of your environment.

Be aware that the changes to your $PATH are only additive. If you already have a global npm modules folder in your path, it will stay in your path. This could result in a global module that was installed on your system becoming available in your activated environment.

To deactivate an environment, the stop command can be used. This command will first try to determine if there is an active environment. If both $NEN_OLD_PATH and $NEN_ENV are unset, it is assumed that there is no active environment and the command stops.

If at least one of these variables is set, the following things happen:

• $NEN_ENV is unset.
• If $NEN_OLD_PATH is set, it is copied into $PATH and then unset.