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Justfiles - universal command control

Dion Whitehead

just solves a set of complex problems:

I want a single command to give me a CLI menu, where ever I am

I’m tired, and forgetful, and I just want this repository to build or test or deploy, and I don’t want to remember all the specifics, I just want to get things done and move on.

When you have multiple repositories you create scripts + tools for

  • CI operations
  • Development
  • Testing
  • All kinds of other tasks

You want to organise these commands, so you put them in a Make file or some custom CLI thing.

But:

  • the custom thing isn’t easily transferrable to other projects/repositories
  • Make is very specific, and has a bunch of ugly workarounds for doing simple things (e.g. .PHONY)

so you and up with a bunch of kludge.

Enter just.​

just is exactly what I needed:

  • simple well formatted commands in any language
  • introspection
  • the utilities you need when munging strings/paths etc

Now ALL my projects have a justfile in the root

I expect the following:

  • Most common commands FIRST (ie. NOT alphabetical order)
    • test, deploy / publish
  • Commands check for dependencies and libraries/modules at runtime, and automatically install if needed
    • Don’t make me write commands for no reason, there’s no reason to not automatically install e.g. npm modules if they are missing.
  • List various links e.g. to the github repo, to the published URL endpoint, to the docs

I alias just to j so that I am just j'ing everywhere. It’s short, fast, and gets me reliably building/publishing even if I have forgotten all the details of the commands.

Sharing​

just on it’s own doesn’t solve the problem of sharing complex commands. That’s where deno comes in. It’s a single binary, running Typescript. I know Typescript is not everyone’s cup of tea, but it’s typed, gets the job done, and the URL imports make sharing between repositories MUCH easier.

Basically before URL imports, I struggled with how to share complex build/publish/deploy scripts.

Just Words of Wisdom (To Myself) about just etiquette​

Always include the full path of commands​

If you document something with what <command> you should run, e.g.

# And then you type: 'just <command>'

but you are </over/here> but you have to be </somewhere/else> then please include the full path so there is never any doubt and you don’t have to go fd'ing: '</be/specific> just <command>'. It doesn’t have to be this exact formula, but try to remove this kind of friction.

Include links to important locations​

See the links at the bottom, they are a click away