Book: System Design Pocket Guide: Interviews — 15 Real System Designs, Step by Step
Also by me: Thinking in Go (2-book series) — Complete Guide to Go Programming + Hexagonal Architecture in Go
My project: Hermes IDE | GitHub — an IDE for developers who ship with Claude Code and other AI coding tools
Me: xgabriel.com | GitHub
"Design a feature flag service" sounds soft. It's the kind of prompt candidates think they can wing because they've used LaunchDarkly and Unleash. Then the interviewer asks the follow-up: "Your SDK ships in 100,000 production processes. How do they know when a flag changes?"
