I wrote a book — The newline Guide to Bash Scripting! I’ll let the intro speak for itself:

It’s aimed at developers who want to get the job done right the first time, and make sure maintenance is a breeze. Topics include:

  • how to find help on arbitrary commands
  • how to structure a robust and maintainable script
  • editing commands and interacting with the terminal efficiently
  • tools for dealing with version control, JSON, XML, text encodings, images and compressed files
  • quality assurance
  • … and much more

[…]

Bash is the Linux glue language, so this book is aimed at software developers mainly working in some other language. We assume that you have working knowledge of programming concepts like variable assignments, loops and files, and at least a passing familiarity with interactive shells.

[…]

This book was written using Bash 4.2 and 5.0 on Linux. The majority of the contents should be applicable to versions long before and after those, and to other Unix–like operating systems. However, since everything on Linux is configurable, absolute statements such as “$PATH will not be defined in a crontab” should be treated as a pragmatic shorthand for providing a virtual machine with the configuration I used when writing. It is not even theoretically possible to write a piece of software which will behave the same no matter how and where it is run. So the only way to know what some command will actually do is to run it, and no statement in this book should be treated as absolute truth. In the same vein, the code in this book is written to make a best effort at doing the right thing in a reasonable set of circumstances.

I’m very proud to have written this book. I would’ve been super happy if it sold five copies, so I was very pleasantly surprised to find it sold over 100 copies in the first week. Allow me to finish with the acknowledgements:

Thank you to Nate Murray, my publisher, for his advice and endless patience, Gillian Merchant for her excellent review of later revisions, my partner for discussions about form and content, all my encouraging friends, family, colleagues at Catalyst and Toitū Te Whenua, and Andrew Maguire and John Billings for reviewing an early draft of the book. Special thanks to all the Bash community contributors on Stack Overflow, Unix & Linux Stack Exchange and Greg’s Wiki, which are treasure troves of information about all things Bash.