Devenv is a tool for [[NixOS]] that allows importing and creating an environment that allows certain tools to be available within a directory.
It allows for easy enabling of certain tools without polluting the global namespace, e.g.
```nix
languages.ruby.enable = true;
```
It also allows scaffolding project environments. Here's a Wordpress instance locally, for example: https://devenv.sh/integrations/wordpress/
It doesn't start until you enter or start the environment.