I have a PHP app which is very large. There are usually 2-3 developers working on it full time and we are getting to the point where we are making changes and creating bugs (cough features!). The software isn't complex per say, just there is a lot going on (35~ controllers, about the same models, etc).

Even being careful it's easy for a change in this view (tweaking an id on an element) to wreck an ajax query happening under some special condition (logged out while standing on one foot).

Unit tests are the first things which spring to mind, but we tried these on another app, and it's so easy to forget them / or spend more time writing tests then doing tests. We do have a staging environment where code gets checked over before pushing live.

Maybe we need a part time Q/A person?

Anyone have any suggestions/thoughts.