A record of shipped volume. You have built agentic coding tasks or environments and can show us how many you personally drove and what they cost to produce.
Experience scaling that output through automation rather than through more people doing more manual work.
Strong software engineering fundamentals and fluency in several languages that holds up in production code.
Real experience with production software. Large codebases, build systems, testing, deployment, on-call, and root cause analysis. You know what real engineering work feels like because you have done it.
An adversarial mindset. You look at a grader and ask how a model would cheat it, and then you fix that.
A clear sense of what frontier coding agents can and cannot do, and where they cut corners.
Ownership. You build, debug, and ship without much supervision.