I'm starting part-time study for a joint honors degree in philosophy/math at the university where I work as a full-time web dev this September, ten days before my 30th birthday. I'm glad to hear that other people have been there, done that, and got through it.
You and I will have a very similar story. The only difference is that I started working as a full-time web developer at my university after I was already taking classes here... I got the job a couple of weeks after my 30th birthday.