Find hidden bugs in your code with minimal repros
A .NET developer used the GPT and Opus models through Copilot CLI to hunt for bugs in the JIT compiler, the part that translates code while the program runs. The agents found 180 bugs, each with a minimal C# repro using only safe code. Most had been hiding from his team for many releases. He tracks the findings in a list on GitHub, but he works on the compiler himself and can judge each finding, which a beginner cannot.
Done with CopilotModerate
What was done
A .NET developer used the GPT and Opus models through Copilot CLI to hunt for bugs in the JIT compiler, the part that translates code while the program runs. The agents found 180 bugs, each with a minimal C# repro using only safe code. Most had been hiding from his team for many releases. He tracks the findings in a list on GitHub, but he works on the compiler himself and can judge each finding, which a beginner cannot.
How to do it
- Paste the prompt into the tool, and replace the text in brackets with your own.
- Read the answer through. Do not send, delete or publish anything until you have seen it yourself.
- Check the original before you trust a figure, a name or a date.
Try it with Copilot
Look for bugs in [module] by writing small test programs that give a wrong result or crash. Each finding needs a minimal example in plain, safe code, the expected and actual result, and which versions it affects. Check that it has not already been reported. Show me the list before anything is filed as an issue or changed in the code. You are done when every finding reproduces with one command and I have approved which get filed.
Replace text in brackets with your own.
@EgorBo on X ·