For the most part you were on your own. I used books myself since I didn't have colleagues back then. But software was in many ways simpler. The complexity was

For the most part you were on your own. I used books myself since I didn't have colleagues back then. But software was in many ways simpler. The complexity was in squeezing out performance rather than piles of abstraction layers on top of one another. Knowing the hardware was more important and that was gleamed through trial and error. The internet enabled the complexity that made software development dependent on it.