[2026-06-26]

- annotations do not work properly because macroexpansion creates an entirely new body for lambdas
- we realized that we are handling macro application in two separate places: pit_expand_macros expands lambda bodies, and pit_eval expands macros encountered while evaling. we ought to unify this so that only one is used (probably pit_expand_macros, because we need to expand macros eagerly to identify free variables to capture)
- we probably can make pit_expand_macros and pit_eval much nicer
- we can probably make pit_expand_macros operate in place
- if we want to be really smart, cool, happy, rich:
  let's just make stuff translate to a little VM before it evaluates, and let's store VM programs as functions instead of sexps