A legacy platform re-architected for scale, cutting page load times by more than half and clearing the path for the product roadmap that technical debt had frozen.
The platform's original architecture had shipped fast in the early days but hadn't been revisited since. Average page loads stretched past four seconds, database queries slowed under concurrent load, and every new feature request meant untangling more of the monolith. Engineering time was going into keeping the lights on rather than building.
Mapped the legacy stack end to end and pinpointed the actual bottlenecks — unindexed queries, a tightly coupled monolith, and no caching layer.
Migrated core services to a modern, modular stack behind a clean API layer, shipped in stages so the platform stayed live throughout.
Added caching, optimized slow queries, introduced a CDN, and split code bundles to cut time-to-interactive.
Rolled out behind feature flags with full observability, so regressions surfaced before customers ever noticed.
Average load time dropped to 2.1 seconds, a 55% improvement over the legacy platform, and the new architecture comfortably handles three times the concurrent users. Just as important, the engineering team went from firefighting to shipping — the roadmap that had been frozen for a year started moving again within weeks of the rebuild.
“We'd been afraid to touch the codebase for a year because everything was so tightly coupled. Unimix rebuilt it under us without a single day of downtime.”