See the official blog post for more details: https://pyrefly.org/blog/v1.0/

I migrated a small python/django backend project at work from basedpyright to pyrefly 1.0 yesterday to try it, and the migration was painless: just running pyrefly init converted the basedpyright config to a pyrefly config in the pyproject.toml.

The typecheking phase went from ~3/4s to 0.5s which is very nice when ran with pre-commit hooks. It also caught some unnecessary type conversion that basedpyright missed (ex: calling str(value) on a value that is already a string).

I haven't toyed too much with the LSP in zed, but I did not feel anything was missing for now.

I will try to migrate larger backends in the following weeks to see how it goes.

Anyway, it's very cool to see a new stable and fast typechecker for Python ! :)