Neither. We used Katalon for a while (Selenium based), but there are a lot of downsides.
- It’s complex to rerun tests when you changed your data, unless you add scripts to undo everything so you can start over. If you have a lot of integrations this won’t work at all.
- You can monitor if processes finish (succesfully), but it’s difficult to have your test suite evaluate the result if that depends on data or, even worse, document contents or integration with other applications.
- It’s a ton of work to keep your test scripts up to date with your model and pages. Every little change can ruin your test script.
If you really want to build something like regression tests, build it in Mendix itself so you can reuse existing flows. There are modules available to build your scripts that even (optionally) rollback changes after the test is done.
Based on my testing experience with Mendix, I would recommend the following steps:
I hope this helps you out, please let me know if you have any further questions, or mark the question as answered if this completely answers the question.