Distributed report service
Designed & built30s → under 5s
The problem: reports took ~30s and froze the browser while dozens of data jobs ran one after another.
What I built: an event-driven service that runs the jobs in parallel across isolated workers and streams results to the page as each one finishes, with crash-safe checkpoints so a run resumes where it left off instead of restarting. Load time dropped from ~30s to under 5s, with 80–90% smaller payloads.