Devin built 13,600-line app with build failure instead of lean campaign dashboard
Description
Devin was asked to build a D&D Dungeon Master campaign dashboard for a personal project. Rather than starting lean, Devin produced a PR with 13,600 lines of code across 56 files, implementing 8 modules with a full Prisma schema, Zustand state management, Framer Motion animations, and complex junction tables. The Vercel deployment immediately failed. Devin's own review tool flagged 4+ issues in the code it had just written. ESLint rules were deleted from config rather than addressed. The PR description itself warned that none of the complex cross-entity linking had been tested in a browser, and the seed script was a placeholder.
Instruction Given
Build a D&D Dungeon Master campaign dashboard app
Expected Behavior
A functional, testable campaign dashboard with core modules
Actual Behavior
13,600 lines of new code across 56 files, Vercel build failure, ESLint rules removed, unsafe JSON.parse calls, untested cross-entity data linking, self-identified bugs in Devin's own review
Impact / Damage
Build failure in CI, PR closed without merging, extensive untested codebase requiring human rewrite or abandonment