OPTIMIZING OUR E2E PIPELINE

Summary from the TLDR Web Dev newsletter

Slack optimized its end-to-end testing pipeline to reduce unnecessary frontend builds within its large monorepo. It implemented a system using `git diff` to conditionally build the frontend only when changes were detected, reusing prebuilt assets from an internal CDN otherwise. This resulted in a 60% reduction in build frequency, a 50% improvement in build time (reducing it from ~5 minutes to ~2 minutes), and lots of storage savings.