We need more and better tests.
Every functionality should be tested using unit test, test script or similar.
Unit tests might be best to test methods and properties.
Test script can be helpful to test functionality that involves multiple methods and properties, like we do in v4.8
Test scripts can also be used to provide sample code for the documentation of certain functionality.
At least every new or highly modified functionality should have a test script. And over time we should create test scripts for older functionality as well.
I believe unit tests can be run during compilation, so every build will have been tested (more or less).
For the test scripts in v4.8 I created a testing tool. That should also be run more or less automatically and the testing results (currently a XML file) should be published to a website so everybody can see the daily/weekly tests.
Perhaps the DotSpatial guys can tell us how they do it?