Web3.py v7 introduced a migration problem that was much more painful than a normal dependency upgrade. It changed middleware architecture, provider names, exception imports, and namespace usage in ways that can easily break production code if migrated mechanically.

I built Web3.py v7 Zero-BS Migrator to automate that upgrade with a hybrid approach: deterministic AST transforms for statically provable changes, and a tightly scoped AI rewrite layer only for middleware patterns that cannot be translated safely with pure syntax rules.

Project links:

DoraHacks submission: https://dorahacks.io/buidl/43676

Demo video: https://youtu.be/f2sC1IJPfpc

GitHub PR: https://github.com/codemod/useful-codemods/pull/29

Live app: https://web3py-migrator-web.vercel.app/

The problem

The biggest breaking change in Web3.py v7 was the move from functional middleware to class-based middleware.…