I wrote a chess playing service to teach myself app engine a while back, and I wanted to verify valid moves on the client before sending them to the server, as

I wrote a chess playing service to teach myself app engine a while back, and I wanted to verify valid moves on the client before sending them to the server, as well as verify them on server. I didn't want to write that logic in both javascript (for client) and python / go (for server) and create a suite of tests to attempt to verify that the server and client logic was equivalent. I looked around for ways to either run (minimal) python functions in javascript or else run (minimal) javascript functions in python, but at the time didn't come up with anything workable (within the constraints of using GAE). * no classes, objects, function attributes, prototypes, etc etc necessary, just chess move validity checking