gistfile1.txt

```
plugin$ nix-shell
- mutable plugin source, immutable nixops src
- mypy works
- tests work
- `nixops` works, using this plugin


nixops$ nix-shell
- no plugins
- mutable nixops src
- mypy works
- tests work



nixops$ nix-shell --arg plugin ../plugin (not sure if this one is possible)
- mutable plugin, mutable nixops
- mypy checks both plugin and nixops
- tests checks both plugin and nixops
- `nixops` works including the plugin

nixops$ nix-shell --arg plugins "[ ../plugin1 ../plugin2 ../plugin3 ]" (not sure if this one is possible)
- mutable plugins, mutable nixops
- mypy checks all plugins and nixops
- tests checks all plugins and nixops
- `nixops` works including the plugins

plugin$ nix-build
- runs mypy
- runs tests
- produces artifact which can be passed in to a nixops build 
- build result is NOT a working nixops

nixops$ nix-build
- runs mypy
- runs tests
- produces nixops which is functional, but without any plugins

nixops$ nix-build --arg plugin ../plugin
- runs mypy checks both plugin and nixops
- runs tests checks both plugin and nixops
- build result is a `nixops` works including the plugin

nixops$ nix-build --arg plugins "[ ../plugin1 ../plugin2 ../plugin3 ]"
- runs mypy checks all plugins and nixops
- runs tests checks all plugins and nixops
- build result is a `nixops` works including the plugins
```