Skip to content
Agentguiden.no
Submit

Let the agent hunt down a hard bug overnight

A developer on Hacker News writes that he routinely leaves Codex running for a few hours overnight to debug. He points to one specific case: you have a deterministic unit test that reproduces the bug through the front door of your app, but no idea why it happens. The agent can then add debug prints and test hypotheses one at a time. He does not describe a concrete bug, or how often it works.

Done with CodexModerate

What was done

A developer on Hacker News writes that he routinely leaves Codex running for a few hours overnight to debug. He points to one specific case: you have a deterministic unit test that reproduces the bug through the front door of your app, but no idea why it happens. The agent can then add debug prints and test hypotheses one at a time. He does not describe a concrete bug, or how often it works.

How to do it

  1. Paste the prompt into the tool, and replace the text in brackets with your own.
  2. Read the answer through. Do not send, delete or publish anything until you have seen it yourself.
  3. Check the original before you trust a figure, a name or a date.

Try it with Codex

The test [test name] fails every time and reproduces the bug, but I do not know why. Find the cause. Add debug prints, test one hypothesis at a time and write down what each round showed in [log file]. Do not change the test. Show me your hypotheses before you change production code. You are done when you have found the cause, the test passes and every temporary print has been removed.

Replace text in brackets with your own.

Read the original

Hacker News ·

  • Build an app for giving away books nearby

    A participant in a day long Replit buildathon made the app GiveABook. The idea is that books we read once just sit on shelves, while someone nearby might need them. You list the book, drop it off, and it is picked up on Sunday. He writes that the entire app and even the demo video were built with Replit Agent. The post does not say how many people use the app, or what he fixed himself.

    Replit@AThippesh08 on X ·

  • Build an e-ink shopping list for the fridge

    A developer built a fridge magnet shopping list on an M5Stack PaperMono with an e-ink touchscreen. It syncs with a phone web app over Wi-Fi and also works offline. The firmware is about 2,400 lines of C++, and all of it was written by Claude Code. He says the family already uses it every day, but this is the first thing he has built on the device, and only Wi-Fi is used so far.

    Claude CodeHacker News ·

  • Find out why a process keeps dying on your server

    Flavio Copes saw the claude command die within seconds on a small DigitalOcean server. He gave Codex CLI on his Mac an SSH command and a description of the problem, with no hints. The agent stated a hypothesis, read the kernel log and found the Linux out of memory killer ending the process. The server had about 2 GB of RAM and no swap. Codex listed fixes by risk and changed nothing, but he chose a costlier fix himself.

    Codexflaviocopes.com ·

Five agents a day

A short daily email with five concrete examples of AI agents. Nothing else.