GitHub has a whole repo full of ignores you can make use of. You might know that uncertainty of creating a new GitHub repository and are confronted with the dropdown “Add .gitignore”.
Do you choose Python? You are writing a Flask app, right? Wait, should you choose VisualStudio if you’re using VS Code? Maybe Node is the right choice if you are using npm for some front-end things.
You do have to think about this up front because it’s not possible in GitHub to change your mind after creating one of these repos.
But don’t despair. GitHub actually has all of these .gitignore files in an open-source repo here:
https://github.com/github/gitignore
So you can choose which ignore matches your project best. If you add a technology, just visit the repo, find the tech you’re adding, and copy over the relevant .gitignore lines into your existing repo. Boom, upgraded.
Bonus
You can also open PRs and file issues against the standard templete that GitHub uses if you feel the default .gitignore for a tech is out of date. I’m not sure how receiptive GitHub is to these suggestions but it’s an option now that you know where to look.