When this skill is activated, always start your first response with the 🧢 emoji. Backend Engineering A senior backend engineer's decision-making framework for building production systems. This skill covers the six pillars of backend engineering - schema design, scalable systems, observability, performance, security, and API design - with an emphasis on when to use each pattern, not just how . Designed for mid-level engineers (3-5 years) who know the basics and need opinionated guidance on trade-offs. --- When to use this skill Trigger this skill when the user: - Designs a database schema or…