I'm currently developing a Node.js tool. Now I want to write some unit tests, but I never wrote unit tests for a node app before and I don't know which framework I should use. Do any of you have any experience with the available unit testing frameworks? In the past I only used Karma and Jasmine for Angular unit testing.

Well you can still use your Jasmine and also you can try jest, jest is very similar to Jasmine but it gives alot for testing than Jasmine.

Here is a work I did with node, tests with Jasmine and also TravisCI for my build, you can check it out, the maintainability is low because I rushed the project and can refactor later, but i had to make sure I had lot of tests for almost every logic

https://github.com/Frost199/...

Good luck

ava! what an amazing test framework. so modern, so user friendly.

the way it shows differences between expected and actual values is sublime.

very fast also. if you run it on a shell via watch mode, it reruns when you save a file, but you can rerun them manually by typing r