Common pitfalls of GitHub Actions

If you create GitHub Actions via GitHub’s UI by going to the URL of the form https://github.com///actions/new, it provides templates for setting up the build. However, the template is broken.

There are four problems with the default template

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Bad and good ways to test code

Writing tests at an early-stage startup is always heatedly debated. If a function has one call, adding a unit test doubles the number of calls, this not only doubles the current work but even slows down future code changes 2X! Further, if the code is not finalized, it is legitimate to ask why even bother writing test code. Here’s a better way to write tests

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Infinite network timeouts in Java and Go

Java made a huge mistake of having no network timeouts. A network request can block a thread forever. Even Python did the same. The language designers should have chosen some conservative appropriate numbers instead.

What’s surprising is that the Go language repeated it!  Here’s a simple demo

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Android: Catching NDK crashes

On Android catching Java exceptions is easy via UncaughtExceptionHandler. Catching NDK crashes is a bit more convoluted. Since the native stack is probably corrupted, you want the crash handler to run on a separate process. Also, since the system might be in an unstable shape, don’t send the crash report to your web server or do anything fancy. Just write the crash report to a file, and on the next restart of the app, send to your web server and delete it from the disk. I ended up using jndcrash package for this.

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Docker: Be careful about the scratch image

After I wrote my previous post, some suggested that I can cut down the image size further by using a “scratch” image. And that’s true, “scratch i”s a reserved 0-sized image with nothing in it. And utilizing a scratch binary image did cut down the size of the final Docker image from 13MB to 7.5MB. Pretty good, right? Except the image cannot do an SSL cert verification because of the missing SSL certs!!!

Failed to reach google.com: Get https://google.com: x509: certificate signed by unknown authority

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Indeterminate Progress bar is an inferior UX design

60 milliseconds is when we notice something isn’t immediate. Any user interaction, that involves sending data over the network or doing heavy computation on it, usually takes way longer than 60 milliseconds. So, we end with a progress bar. There are two broad categories of progress bars, one that shows the absolute/relative progress, a determinate progress bar, and one that does not an indeterminate progress bar.

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How many source-code repositories should a startup have

Recently, this question came up during the discussion. “How many source-code repositories should a startup have?”

There are two extreme answers, a single monorepo for all the code or repository for each library/microservice. Uber, for example, had 8000 git repositories with only 200 engineers! I think both extremes are wrong. Too many repositories make it hard to find code and one single repository makes it harder to do simple things like testing, bisecting (to find buggy commit), deciding repository owners.

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