Measuring Engineering Performance: Activity Is Not Output

Mon, 06 Apr 2026 00:00:00 -0400

The case for making engineering performance visible is legitimate. Hidden underperformance is a real organizational problem, and managers who avoid measuring their teams are often just avoiding difficult conversations. That much is fair.

The problem is the tool, not the intent.

GitHub activity metrics – PR counts, commit frequency, lines of code – are proxies. They measure inputs, not outcomes. And once any metric becomes a target, it stops being a reliable signal. This is Goodhart’s Law, first articulated in economics but applicable almost anywhere humans are being measured. Engineers are rational people. Tell them their PR count matters and you’ll get more PRs – smaller, more frequent, shallower in scope. Tell them reviews are tracked and you’ll get more reviews that say “LGTM.” You haven’t improved performance. You’ve changed what people optimize for.

Performance on Rough Edges

Measuring Engineering Performance: Activity Is Not Output