pytype (https://github.com/google/pytype https://github.com/google/pytype) is based on symbolic interpretation of python bytecode, but with the data stack stori

pytype (https://github.com/google/pytype https://github.com/google/pytype) is based on symbolic interpretation of python bytecode, but with the data stack storing types rather than values. it works very well and has been running in production within google forever. the nice thing about writing a bytecode rather than an AST interpreter is that you can leverage a lot of the work the python compiler does, and work with the resulting simplified code.