Roadmap

Frontiers, ordered by value: per-name precision past lazy unpacks (a tuple display is the only form mypy's binder distributes — genexp, listcomp, tuple(...), starred, and map all assign the union); unpack-vs-concrete merges (provably unknowable today, but narrower bails are possible); NEP 50's value-based edge cases (out-of-bound Python ints) and union dtypes; the @ operator (mypy consults the method hook inconsistently); ty and pyright (neither offers a plugin API to build the solver on).