# Tweet by [@keefmoon](http://twitter.com/keefmoon) on 2020-04-14 13:26:17 > [!INFO] Archived from [original tweet](http://twitter.com/keefmoon/status/1250052757979123713) In reply to: [@pilky](http://twitter.com/pilky/status/1250043483290775558) @pilky But how many unit tests do you not need to write because the type system makes it impossible to make the mistake that would need testing.