The mission-control flake-parts module enables creating a set of scripts or commands to run in the Nix dev shell. This makes it possible for the project’s user to locate all of the commands they need (to get started) in one place, often replacing the likes of Makefile or bin/ scripts.
Usage
To use this module, add mission-control to inputs,
{
# Inside inputs
mission-control.url = "github:Platonic-Systems/mission-control";
}and import its flakeModule:
{
# Inside mkFlake
imports = [
inputs.mission-control.flakeModule
];
}Add a script (Haskell)
Here we’ll show a sample of scripts that are particular useful when developing [Haskell](/haskell-flake) projects.
Docs (Hoogle)
We can add a convenient script to start Hoogle on project dependencies as follows. As a result, typing , docs in the dev shell will start Hoogle.
{
# Inside perSystem
mission-control.scripts = {
docs = {
description = "Start Hoogle server for project dependencies";
exec = ''
echo http://127.0.0.1:8888
hoogle serve -p 8888 --local
'';
category = "Dev Tools";
};
};
}
The exec option can be either a shell script (string) or a Nix package. The category option defines the group that this script belongs to, when displayed in the menu.
Cabal repl
To start a cabal repl from your devShell on running , repl, use:
{
# Inside perSystem
mission-control.scripts = {
repl = {
description = "Start the cabal repl";
exec = ''
cabal repl "$@"
'';
category = "Dev Tools";
};
};
}
"$@" represents the command-line arguments passed to , repl. This allows us to pass custom arguments to cabal repl. For example, if you wish to run an executable foo from your project in cabal repl, you’d run , repl exe:foo. Similarly, to get into the repl for a library bar you’d run , run lib:bar.
treefmt
If you use the treefmt module for autoformatting the source tree, you can alias it as , fmt:
{
# Inside perSystem
mission-control.scripts = {
fmt = {
description = "Format the source tree";
exec = config.treefmt.build.wrapper;
category = "Dev Tools";
};
};
}
Note that exec in this example is a Nix package.
Tips
wrapperName
If you don’t wish to run your command using , <command> you can change the , to be any string of your choice by setting the option wrapperName, as follows:
{
# Inside perSystem
mission-control = {
wrapperName = "s";
};
}