Ask HN: How to manage software engineers?

I have been running a company for last three years, started right out of college. We were a team of 6 people until last year and have grown to 15 people today. The engineering team is at 10 now and I am slowly transitioning from a "developer" to a manager. Would like to hear your experiences on how to do the job better? Any books/blogs to follow on scaling the engineering management and guiding people? What tools do you use for tracking? How frequently do you give feedback?