Implementation wise, Jejak used Opal so I guess it relies on bytecode modification to do its analysis where my tool relies on ast annotations.�
This implies some difference in features. It seems that Jejak record all calls, all values and all assignments in a method (which is byte code level feature), whereas I record for each ast node if it was interpreted or not (which is ast level feature). I guess there would be a little difference in the use cases.