Cx Dev Log — 2026-04-30

Phase 11 just introduced compound assign lowering on submain, pulling += , -= , *= , /= , and %%= into the IR backend. All in all, 126 new lines in src/ir/lower.rs and three fresh tests. These operators mark their maiden voyage through the IR backend, and while main keeps its 78/78 green tests, submain stays ahead by 22 commits with a 33-day bridge to cross. Compound Assign Lowering Commit 9015aff on submain is the sentinel. Gone is the CompoundAssign stub that only returned an UnresolvedSemanti