Applied via the website. Contacted by a recruiter (aka "talent partner") two weeks later to schedule a screen. What followed was four rounds, for a total of ten individual interviews with nine people (hiring manager's boss, [take-home test based on sample projects], potential teammate, members of four collaborating departments, hiring manager, a second recruiter (for diversity interview), and first recruiter again.
The hiring manager was the last of the main interviews (diversity interview and wrap-up with recruiter were the last of the process). This ended up making the process cumbersome, inefficient, and ultimately not as "candidate-friendly" as GitHub prides itself on being. The outcome was a call from the recruiter a week after the final round of interviews to tell me that the hiring manager has decided to change the job. She then told me that everyone liked me and would welcome me as a contractor if they ever had any openings. So, not fit to do the work as an employee, but somehow fit to do it as a contractor?
Having the hiring manager be the first main interview, like the majority of companies do, could've saved at least three weeks of scheduling, shifting work for, preparing for, and waiting for word of next steps after at least eight interviews.
Another possibility is that the hiring manager and/or the recruiter already decided that I wasn't a fit for the new or existing version of the position but advanced me through to the end of the process (and maybe even selected me for the process in the first place) for diversity "looks"/stats. Though I know that I am qualified for the position (15+ years as a professional writer and editor for recognizable companies and brands), I am from an underrepresented group and have unfortunately experienced similar situations at two other tech companies. I hate to have to consider that, because everyone was so nice, but things in GitHub's process were just odd enough that I can't rule that out.