I don't know what's the issue. PyPy shouldn't have breaking changes. They're targeting Python 2.7.x which is a frozen specification. In the unlikely case that

I don't know what's the issue. PyPy shouldn't have breaking changes. They're targeting Python 2.7.x which is a frozen specification. In the unlikely case that a new release causes code that worked in a previous release to fail, it's simply exposing a bug in either the new or old release.