Process included 4 steps: 1. Short video call with HR. Zack is a best HR I've seen so far, he made overall process as comfortable as possible. 2. Video call with CTO and live coding. Inteview required knowledge of distributed systems, time-space complexity and ability to solve algorithmic challenges. Also we talked about past experience. Dan looks like a great CTO to work with. 3. 3-hour take-home challenge on any language of your prefference. Was really fun to solve and was pretty close to problems that you will face in real life. Main advice is to think about usage of your solution in a large system, rather that feature richness. 4. Day of software development with one of Heap's engineers. I was aware of this step but did not get this far. I've enjoed talking with every person I've met during inteview. Overall process and company is strongly recommended for everybody who is looking for interesting engineering jobs.