He Rewrote Everything in Rust — Then We Got Fired The day his code hit production, the graphs went flat. A month later, HR called us in. ThreadSafe Diaries 4 min read · Jun 12, 2025 -- 65 Share Before the Rewrite, We Were Drowning We were a team of six. Backend engineers juggling microservices, pipelines, devops patches, and postmortems that read like therapy notes. Our stack was typical for a fast-moving startup: Node.js microservices Redis queues AWS Lambdas MongoDB for almost everything We weren’t bad. We just weren’t fast. Services were functional, but brittle. Some mornings, we’d all be staring at Datadog dashboards watching a queue backlog climb past 10k messages, waiting for garbage collection to catch up. We were firefighting. Every day. Then Kabir, the quietest one of us, said, “I think I can rewrite this image pipeline in Rust.” What Happened Next Should’ve Been Obvious We all shrugged. Rewrites never survive. But Kabir didn’t ask for help. He didn’t book design meetings or ask for estimations…