From Zero to Stable: Frontend Platform's Load Testing Journey with k6

The Frontend Platform team built an automated performance regression pipeline for Remix applications using k6 load testing, moving from inconsistent results to reliable, reproducible runs. Changes included switching from ramping-vus to ramping-arrival-rate executors, adding application warmup for V8 tiered compilation, extending test duration to capture garbage collection cycles, removing CPU limits, and standardizing on generation 6 EC2 instances. Test variance dropped from 4x differences in P95 response times to just 10ms, enabling accurate regression detection.