I applied through their Careers page, and received an email from an HR person. He sent me a practical technical assessment - I spent some hours on it and sent it back, and he passed it to their technical hiring team. In a follow up email, he mentioned that the dev team had found an aspect that could be improved, and asked how I'd address that. I was a bit blown away - I did not expect a second chance on the test! I did some more work on it and sent off a second submission, and was invited to an in-house tech interview. I spent an hour with two very personable developers who chatted with me about technical topics for a while, then gave me a laptop and had me work on some code, verbalizing my thoughts as I improved it. Overall I found the process very professional.