97 Things Every SRE Should Know

Chapter 9. There Is No Magic

Bouke van der Bijl

 

When working with computers it’s easy to get overwhelmed with the complexity of it all. You write some code, run it through a compiler, and execute it on your machine. It seems like magic.

But when issues occur and things break down, it’s important to remember that there is no magic. These systems we work with are designed and built by humans like you, and that means that they can also be understood by humans like you. At every step, from the interface on the screen to the atoms your processor is built out of, someone considered how things should work.

I tend to work on two layers at the same time: the code I’m writing and the lower-level code I’m using. I switch back and forth between my work in progress and the source code of the Ruby gem, the Go compiler, or even a disassembly if the source is not available. This gives me context about my dependency: are there comments explaining weird behavior? Should I be using a different function mentioned in the code? Maybe an argument that wasn’t immediately clear from the docs, or even a glaring bug?

I find this context switching to be a sort of superpower: X-ray goggles for the software developer. You can look deeper many times: from your code, to the virtual machine running it, to the C language it’s written in, to the assembly that finally runs. Even then, you can read the Intel x86 ...