JMLR Software

A free course

One fix broke everything. Go back.

I changed one thing and something else broke.

You asked for one small change and something else stopped working. The undo button is a free course of five short lessons. It shows you how to save a version of your app every time it works, so when a fix breaks it, you go back to the version that worked. It uses git, in plain words.

What you get

Tap the button and the course is on the next page. You'll also get one email with this page's link, so it's there the next time. Then one short email each time a new free thing is ready, sometimes ending with a link to a paid course. Unsubscribe in one click.