Nx Remote Cache Server

The Challenge

Every CI run rebuilt the entire monorepo. Developers waited. Cloud bills climbed. The math was simple: we were paying to compile the same unchanged code hundreds of times a day.

My Approach

Built a cache server from scratch using Bun for raw speed. Two-tier caching (hot in-memory, cold in blob storage) means cache hits are nearly instant. If it hasn't changed, we don't rebuild it. Period.

Key Contributions

• Built LRU in-memory caching for frequently accessed artifacts
• Implemented Azure Blob Storage backend for persistent cache
• Added dual-token authentication (read/write) with timing-safe comparison
• Configured rate limiting (1000 req/min) for stability
• Created health checks for container orchestration integration

Impact

• CI pipelines went from coffee-break length to near-instant
• "Works on my machine" became "works everywhere, identically"
• Cloud compute bills dropped noticeably
• Developers actually run the full test suite now (because it's fast)

Tech Stack