We are thinking about implementing sys.settrace or its subset. Currently, the most wanted is the 'line' event (we are trying to create a very simple code-coverage tool using that). I think this feature should be an optional, enabled during the build-time via the compilation flag.

This feature is the first necessary step and can be later expanded to implement #3009 fully.

Do you have any pointers how to do that or has anyone done any experiments in that area?

// cc @matejcik @jpochyla