My entire workflow is based around tens of little scripts I’ve written. Many scripts tend to be unique to a single project.
For example, I’m currently working in a project that’s based on an open source front end framework that has been discontinued for over 5 years. Creating a new component requires the creation of 3 different files with a ton of boilerplate. And there are many types of components that can go in different locations.
A simple Unix script means I can create all with the boiler plate in an instant. If I want to open a component it automatically opens all 3 files. And if I’m working on multiple bugs/features simultaneously I can create “workspaces”, by entering file names in a text file for each workspace and open each workspace instantly (or automatically on switching on my computer).
This is just one, probably least impressive, but extremely useful, piece of functionality I simply won’t be able to do (or if they provide some sort of API, it will require a bunch of code with a foreign API for me to execute).