After submitting my resume and having it approved I was given a choice between a DevOps two-part "essay" question or a coding challenge. This was because I wasn't sure whether I wanted the open DevOps role or the Backend role. I selected the coding challenge as I felt it played more to my strengths than the DevOps questions.
The coding challenge was a real-world parsing question related to their domain. I was asked to spend between 1 and 2 hours on it. Beyond that point, out of respect for my time, I was asked to simply submit what I had if I was unable to finish. I finished it before that time limit, however, so I submitted a working solution.
I then had a 1:1 with the tech lead which was more exploratory into my desires in a new role as well as what work at Gridium was like. This was a half-hour call, if I recall correctly.
I had a group call with about 4 engineers (at once) over a Google Hangout where I was asked a set of questions about a variety of things. This included some questions about architecture, debugging, interpersonal conflict resolution, and my general background. I was given about 20 minutes to ask questions of the group.
It was a very pleasant and professional experience. I highly recommend others interview with Gridium. Gridium correctly identified that I have a collaboration style that wasn't likely to be a good fit within their company. I also came to this conclusion. Another great thing about this process was that the tech lead (who was my point of contact through this process) was transparent about the reasons for not moving forward to whatever the next step might've been (or an offer), which was what I explained. I'm grateful to have had the experience to speak with these fine folk and encourage others to investigate working with them.
The only complaint I had was that expected salary was not discussed at any point, leaving it as a potential issue at the last moment, after both sides had finished investing considerable time. They should probably include a broad range up-front to set expectations, or even ask the candidate what his or her expectations is.