The Principal Engineer is a publication about the reality of shipping production AI, written from the trenches.
Most content focuses on what’s possible. This is about what actually works, what breaks, and what it costs. We’re talking about evals that go beyond vibes, practical FinOps for engineering teams, and agent architectures that survive contact with real users. It’s the engineering work required to keep AI-generated code maintainable six months down the line.
Written by Wille Faler. 20 years building production systems at banks, fintechs, and startups.
