From wikipedia:

Identicon is a visual representation of a hash value, usually of an IP address, that serves to identify a user of a computer system as a form of avatar while protecting the users' privacy. The original Identicon was a 9-block graphic, and the representation has been extended to other graphic forms by third parties.

Assuming you have Elixir installed on your system:

$ git clone [email protected]:alephmelo/identicon.git
$ cd identicon
$ iex -S mix

It will enter the Elixir interpreter.

iex(1)> Identicon.main("test")
:ok

This identicon is the output for the string "test".