Hi, during my work with context I wrote a bunch of fewliners mainly to test how to do things. When there change from mkii to mkiv occured many of my mini-tests failed and later with the growing of mkiv restartet to work - some just without adaption.. some with some adjustment to a new syntax. I realize that they have the same functionality like unit-tests - just instead of comparing classes and variables - a pdf-output is visually compared. So I like to suggest to introduce unit tests for context. It would a) increase the quality of context as it makes the testing easier for the developer b) it also would be a great source of minihowtos for learning context. Before I write my technical ideas about this I would like to know what are you thinking about this idea?