[pizza234]

> Many more elaborate projects exist. My favorite is the one that compiles something similar to Turbo Pascal to C64 6502

It depends on the purpose. The reference IDE is intended to produce real-world programs (it includes tools for sprites, music etc.), while high level language compilers are mostly academic, as they're not performant enough.

[zozbot234]

llvm-mos https://github.com/llvm-mos/llvm-mos seems to generate good enough code - more than competitive with other high-level languages for the 6502, though perhaps not so much with manual assembly coders.