paddo.dev: 291 Opus 5.5 agents moved a Firebase app to Postgres, Better Auth and SvelteKit in about two days with a 33-minute cutover
paddo.dev·low signal
In his 09-26 post the author says the agents first wrote a plan of 84 work items, each sized for one agent. They then moved 705,614 Firestore documents, 237 API routes and 52 admin pages. Review became the bottleneck ('agents write commits faster than anyone reads them'). An account-linking bug still got into the code, and a pager broke on page two in production because dev never had a page two. His argument is that well-documented boring tech gives agents better priors than vendor SDKs, though he publishes no token or cost figures.