Bossy Lobster

A blog by Danny Hermes; musing on tech, mathematics, etc.

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The Node.js CA Footgun

Door to Nowhere

This is a story of a brief outage caused by a slightly unintuitive API1 that has some very sharp corners for the uninitiated. The outage, though brief, was of the "wake up at 4am" variety so the lesson was especially salient.

This is not a post trying to tear …

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Custom GitHub Actions

The "obvious" way to write a custom GitHub Action is using Node.js, however it's not the only way. As it turns out, a GitHub Action really just communicates with the "orchestrator" via environment variables (as inputs) and STDOUT (to produce custom outputs).

Options

When defining an action, there are …

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HTTP Is Just Text

This is a tiny little note that can help with debugging in some situations. We'll use netcat (nc) to view the raw data sent to and returned from an HTTP server1.

Capture a Request

We'll run a dummy listener via nc and directly inspect the body of an HTTP …

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Broken Pipe in a Haystack

Broken Pipe

I recently put on my detective hat and tracked down a bug in network error recovery in a popular PostgreSQL library. Below, we'll walk through the process of bugfinding and iteratively making the feedback loop smaller and smaller. In order to find and fix the bug I

  • Confirmed the root …
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pow Confusion

In my first summer of graduate school my code suddenly stopped working because Fortran and Python (via pow() in C) do exponentiation differently. Once I debugged and understood the problem, I learned about the highly optimized assembly code produced by Fortran for integer exponents.

To give a sample of the …