It is not my intention to put any employee's tenure at risk in writing this review, so I will try to keep this as general as possible.

There was a minor snafu with the payment method HR used for the hotel room. I took the liberty of getting a rental car and going on a brief tour while waiting.

I showed up at the scheduled time for the interview. There was about a 40-minute delay (for me, this is not unusual as of late).

Friendly people, but overall an emotional atmosphere showing signs of chronic stress. Frankly, this made it difficult to focus on their coding questions and give coherent answers.

I am terrible when it comes to scribbling things on a whiteboard, so they were accommodating and set up the interview machine to use Notepad++ and screen sharing with interviewers who were remote.

I would ask how they identify project leadership roles with each new pair of interviewers, and got worryingly different answers with each meeting. Human beings naturally organize themselves into hierarchies when confronted with challenges as a group, regardless of the cultural precedent. I felt it was reasonable to keep probing on this subject, even though I am aware Valve advertises a flat, self-organizing structure. Their reactions ranged from concern to mild agitation, but understandable considering the context.

The interview was cut short after meeting over a conference call with Gabe. Prior to him joining that particular meeting, I was met by an employee who seemed extraordinarily nervous, asking me the same question multiple times after I provided an answer in the first phrasing.

The question was essentially about cloth simulation using FP math at a distance from the origin large enough to cause precision issues. My first answer was that it would require some degree of forward error analysis to determine where the most error was being introduced, and my second answer was to successively double the time step (or increase it as a function of distance) until the simulation seemed to work. It is ultimately about dealing with problems encountered with NLPs in general, and can honestly take several days to weeks to diagnose and resolve correctly. I'm not sure if the person interviewing me was aware of this.

Gabe had an interesting statement and question for me. I will abstain from discussing for the time being. However, I was left uncertain about his mannerisms or the impression I left, as I did not have a visual (audio only).

Write an algorithm that merges an input set of intervals into a minimal set of non-overlapping intervals.

Write a calculator (as in, a gradeschool calculator).