復古打字機 — Mac OS X App 官网
This WriteTyper app works on Mac OS X 10.10+, writen in
Swift 2.0, based on NoisyTyper. It can make old typewriter sounds when you keypress, let you more enjoy the time of coding or writing.
It's very easy to install this app.
Download the app, double click to run it. And then go to the System Preferences -> Security & Privacy, enable Accessibility for WriteTyper. At last, quit it and reopen.
Notice: for it to work, Accessibility for WriteTyper must be enabled.