The tips and tricks below originally appeared as one of Google's "T esting on the Toilet" (TOTT) episodes. 

I start every bash script with the following prolog:

#!/bin/bash
set -o nounset
set -o errexit

Use functions

• Favor $() over backticks (`)
• Favor [[]] (double brackets) over []
• Avoiding Temporary Files with <()

But there is a good standard UNIX tool. By standard I mean it actually has robust documentation, that many forgot. Or never learned? I’m talking about make. More accurately, this article focuses on GNU make. It’s available on macOS, Windows, Linux and most other operating systems.