Vanilla, a term that took me a while to truely understand and even longer to include it in my vocabulary. I understand it as writing it all yourself from the ground up without any additional moving parts. Wiki says

Computer software, and sometimes also other computing-related systems like computer hardware or algorithms, is called Vanilla when not customized from its original form, meaning that it is used without any customizations or updates applied to it.

This code was built from the ground up with nothing but tmux and vim as a text editor. I didn’t even have an internet connection as most of this code base was built on the bus to/from work. Here’s the file structure:

~ $ tree inventory/
├── input
│   ├── bufferinvoker.rb
│   ├── commands
│   │   ├── addcommand.rb
│   │   ├── checkcommand.rb
│   │   ├── command.rb
│   │   ├── ordercommand.rb
│   │   └── showcommand.rb
│   ├── inputbuffer.rb
│   ├── inputhandler.rb
│   ├── invokers.rb
│   └── testing
│       └── buffer-test.rb
├── output
│   └── outputbuffer.rb
├── run.rb
└── system
    ├── bag.rb
    ├── exceptions.rb
    ├── inventory.rb
    └── testing
        └── bag-tests.rb

6 directories, 17 files

The system is executed via the run.rb command, in my last article I spoke about writing scripts in ruby. The thing that stands out is the low number of test files, but I promise, like a good programmer I used TDD.


Essentially I used the command design pattern for input commands. This allows us to seperate out the class that invokes the command from the one that executes it. I used the strategy pattern to design the internal parts of the system. Creating my own data structure and a singleton class which inherits it.

Now I know this article is titled “Vanilla Ruby Fun” but it’s sort of pun title. While writing ruby is a lot of fun, as developers in the ruby community, we need to be aware that this isn’t the only way to write ruby applications. Frankly, this is a terrible way to write ruby there must be a better way.


This app was particularly craft from the ground up as a lesson in ruby design patterns in practise. I’ve since released this version on github and moved on to using some of the tools the ruby community has come up with, hence no longer vanilla ruby.