My First Two Weeks as an Agentic Engineer

A developer at Codeminer42 spent two weeks building two real-world projects using only AI tools (Claude Code), with no hand-written code. The first was a Rails 8 piano learning app with MIDI integration, AI-generated study guides, and ~288 tests built in 5 days. The second was a Wear OS interval training app in Kotlin with 157 tests built in 3 days. Key lessons include: starting a CLAUDE.md file from day one, using iterative audit loops to improve code quality, breaking tasks into small scoped requests, and letting tests (not Claude) determine when work is done. The author emphasizes that software engineering fundamentals matter more in agentic workflows, not less, since the bottleneck shifts from writing code to clearly describing problems.