Switching between saved views on a board in my tracker costs zero Firestore reads. The board's active tickets are loaded once and kept live, and every filter, sort, group-by and swimlane is a pure function run over them in the browser.

The constraint that forced it: Firestore cannot OR across fields, and every combination of filters you want to query needs its own composite index. A tracker with user-defined views over custom fields would need thousands of them.

I'm Panth, and I lead the software team at Oizom. This is from ticket-tracker , my open-source board. Its decisions page lists the choices that are expensive to reverse, each with the alternative that was turned down. This is D5.

The decision

Chosen One live query per board over its active tickets.…