Tried to move some excel generation logic from epplus to closedxml library.
ClosedXml has basically the same API so the conversion was successful. Not a one-shot but relatively easy with a few manual edits.
But closedxml has no batch operations (like apply style to the entire column): the api is there but internal implementation is on cell after cell basis. So if you have 10k rows and 50 columns every style update is a slow operation.
Naturally, told all about this to codex 5.3 max thinking level. The fucker still succumbed to range updates here and there.
Told it explicitly to make a style cache and reuse styles on cells on same y axis.
5-6 attempts — fucker still tried ranges here and there. Because that is what is usually done.
Not here yet. Maybe in a year. Maybe never.