I have been working at Black Mountain Systems full-time
Black Mountain Systems is a fantastic place to work. The work can be challenging, but you will be surrounded by incredibly intelligent people who are around and happy to help. While it's no longer a tiny company, the startup culture is still very much intact. BMS puts a lot of thought an on every person they hire to keep the collaborative and positive culture alive. Also overall great from a work/life balance perspective.
Sometimes workloads can be highly variable, but it's not unusual for the industry.
Advice to Management
Keep the great, small company culture for as long as you can.
I applied through a staffing agency. I interviewed at Black Mountain Systems (San Diego, CA).
Interview process was very fair. There is a take home test to first evaluate you aren't an idiot. Then in person interview which was very reasonable. Not algorithms but more, here are your requirements, build this.