Hello, Eugene! I built this application for a code challenge.

• The app consists of two modules: Airfy.Encryptor which takes key and data and returns encryption result. The second module is Airfy itself. I decided to expand challenge a little bit so that I added command line interface to it (I didn't have experience with command line interface before);
• This encryptor uses symmetric encryption. I decided not to fight against gpg for this simple task;
• It uses siphash alghorhythm implementation for elixir. I found it stable & well maintained enough;
• It's a test covered app. It has 1 test :) There is no need to cover simple pattern matched interface by big test suite;
• It's ready to be released with exrm or distillery.

Total time it took to implement, test & document: 2 hrs 10 mins

./airfy --key-path priv/key.txt --message "I love elixir"

• mix deps.get
• Generate key file with random content base64 /dev/urandom | head -c 1000 > priv/key.txt
• mix escript.build
• Run command line