UpliftUplift

The reporting layer was slow, and speed is what got the migration funded. What decided how it was done was the rest of the brief: every query already written had to keep returning the same answer, and nothing could go offline while it moved. That rules out the clean version, where you build the new warehouse, cut over on a Sunday and fix what breaks on Monday. So the BI layer was re-pointed onto the faster engine with the existing queries still running against it, and the measure of success was that nobody noticed. On the API side the load is the argument for serverless rather than the fashion. It is quiet for long stretches and then it is not.

Lambda and API Gateway underneath, Next.js in front. The platform is Beneathatree's; these parts of it are mine.