https://medium.com/blackode/the-mystery-of-string-concatenation-io-lists-elixir-expert-d21d1f0a2aba?sk=41a7ba4bcdaf552b26e5277a0e1784c3

In this article we are going to see the optimal way to develop a big string from the pieces of strings. We also look into why IO Lists are used for rendering templates in Phoenix and why this is the best approach.