Worklog for task "Migrate the website to a new engine"

New HAIH Experiment: Brownfield on pivkarta.ru

The task was set a long time ago as an upgrade of the old haih-agent, but since then a new HAIH approach has emerged, which we are currently testing in practice at haih.site. Current work on the concept is being conducted in the task "Develop and launch the website", and pivkarta.ru looks like a good next guinea pig for the new engine/approach.

If haih.site is a greenfield experiment on "how quickly to assemble a sufficient architecture from real requirements," then pivkarta.ru can become a brownfield experiment: how quickly an AI agent can analyze an existing product, preserve its real requirements, and gradually replace the outdated architecture without dragging its historical baggage into the new system.

It is important not to start with a total rewrite and a pre-selected "correct stack." The existing MySQL can be left as a working persistence boundary, and for the first vertical slice, connect to it via Knex, build a new typed API on top using Pothos/GraphQL, and use codegen/Apollo + React on the client. That is, migrate primarily the requirements and behavior rather than the old architecture.

The first practical experiment: choose one real user scenario and run it end-to-end through the new system (React → Apollo → GraphQL/Pothos → Knex → existing MySQL), recording the implementation time, issues, verification methods, and resources. The existing baseline of the old system (~2 GB RAM according to current measurements) will allow comparing the result not only by functionality, but also by runtime cost.

This should become the second type of evidence for HAIH after haih.site: not only "how fast AI builds the new," but also how fast it is able to rethink and displace legacy along working verticals.