Personal website of Andreas Fertsch-Röver
Shell job control does not survive an agent's stateless tool calls. Use the harness background primitive when there is one; otherwise detach the process, log to a unique file, and persist the PID and exit code to disk so a later call can poll them.
A JVM-wide singleton cache and default JVM reuse in Surefire hid an order-dependent test bug behind a fully green suite, until one flag flipped the run order and made it fail on demand.
Two regressions that only surfaced after deploying a javax-to-jakarta, EAP7-to-EAP8 migration to a real runtime, and why a free smoke test would have caught both.
Why teams should extract company-specific skills from complex domain work, and how to embed institutional knowledge so the second migration is faster than the first.
From tangled horizontal layers to vertical Boundary-Control-Entity slices, and why they are a perfect fit for LLM-assisted development.
Key ideas distilled from talks by Rich Hickey, Alan Kay, Guy Steele, and others — on simplicity, state, design, and the gap between what programming is and what it could be.
How borrowing MUST, SHOULD and MUST NOT from RFC 2119 turns bloated AGENTS.md files into compact, enforceable rule sets.
How I use git worktrees and Claude Code to work on multiple tickets in parallel.