There are actually two different SRE roles: the one people are describing above where you are 85-99% of the way to SWE (Software Engineer), and you have sysadminy experience, and another one where you are 100+% of the SWE bar and optionally have sysadminy experience. The former is called SRE-SE (Systems Engineer), and the latter SRE-SWE.

SRE-SE interviews are super heavy on the sysadmin stuff usually, with less (but still significant) attention paid to SWE skills, whereas SRE-SWE interviews may not even have an SRE component (it's possible for candidates in the 'normal' SWE hiring pipeline to be shunted to SRE-SWE post-interview).

Yeah a lot of people don't understand this distinction. You have your pure SWEs who were hired that way who then were either picked for or switched to SRE-SWE. Then you have people who were recruited into SRE-SWE from the beginning. People in SWE and SRE-SWE job classes can freely move between them. Then finally you have people who were recruited as SRE-SysEng, or were recruited as SWEs and didn't quite make the cut. These folks have to do a transfer interview to jump to the SWE or SRE-SWE roles.

Could you speak to the dev/programming skill set need for the SRE-SWE vs the SRE-SE?

I'm an SRE-SE and regular do phone interviews for SRE-SE candidates.

While I do tend to spend more of the interview time talking about sysadmin tools, operating systems, networking, databases, security and troubleshooting, I still expect candidates to have reasonably good coding chops.

The difference is that the coding questions tend to be more task-oriented or procedural (i.e. log processing, building automation pipelines, implementing standard unix cli tools, etc.), rather than the algorithmically challenging or math-oriented problems that we'd usually ask SWE candidates.

Both the SE and SWE side SRE candidates need to be able to design and reason about large systems, making trade-offs between performance (especially latency), redundancy and cost.

Thanks. Is being well-versed in C a prerequisite for the role then? I'm imagining you need to be fluent in at least one statically compiled language or ???

In my interviews you code in whichever language you prefer. Some interviewers will ask you to use a specific language that's mentioned on your resume. In general I think that if you show strong coding skills in some language, it is believed that you won't have much trouble teaching yourself the languages your team uses (typically some subset of C++, Java, Python, Go, Borgmon).

Weirdly my experience with interviewing for an SRE role was the reverse: the phone screen was pretty much a straight programming problem (in a Google Doc, ugh) but then one of the on site interviews was very shell programming focused.

I guess to a certain extent it must be the luck of the draw - mass log analysis did crop up in my on-site interview as well, so that seems to be something of a theme, although it was more from a high level systems building POV for me.

I interviewed as SRE four months ago and I got a very typical programmer phone screen and interview, just exactly the kinds of whiteboard CS questions you expect Google might ask. (My bigger strength is on the programming side instead of the ops side, so I think perhaps they explicitly tailored the interview to measure that.)

That's interesting, when I interviewed (admittedly it was like 8 years ago), the first interview was standard CS questions and the second interview focused on deeper C++ questions (things like analyzing how a vtable is constructed).