Show DEV: I Built a Bayesian GitHub Action to Find the Commit That Broke Your C++ Build

Hey DEV community! 👋

I've been experimenting with probability theory and wanted to see whether Bayes' theorem could help identify which commit caused a failed CI build .

So I built BayesCI , an open-source GitHub Action powered by a small Bayesian engine written in C, with Python handling Git analysis and compiler diagnostics.

The problem

Imagine you've made several commits, pushed your changes, and suddenly your C++ build fails:

undefined reference to `calculate_total' collect2: error: ld returned 1 exit status

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The compiler tells you what failed, but not necessarily which commit introduced the problem.

That's what BayesCI tries to help with.

How it works

BayesCI:

Reads GCC, Clang, linker, and CMake diagnostics.

Examines commits since the last successful build.

Analyzes changed files, symbols, lines, and build configuration.

Uses Bayesian ranking to identify…