Secure Score exports from large tenants run to thousands of rows, and everything had to be parsed where the data was allowed to live: the browser. A naive synchronous parse locked the UI for seconds — unacceptable for the executive audience the tool served.
I chunked parsing so the main thread yields between batches, computed category aggregations incrementally as rows streamed in, and memoized the filter pipeline so toggling a domain re-ran only the affected slice instead of the whole dataset.
Filtering also exposed data-quality landmines: rows without color coding were silently inflating high-impact counts. Explicit exclusion rules — validated with BlueVoyant’s analysts — made the numbers match what Microsoft’s own console showed, which is what made the tool credible enough to put in front of enterprise customers.