[tmhedberg]

He's a Tech Lead Manager, or TLM, which means he's an engineer who also manages the team he's a part of. In some cases, dev teams have SRE counterparts who take the pager responsibilities, among other things. But not all services at Google have SRE support, and for those that don't, the developers themselves are usually on call. That includes the dev team's TL, or TLM, as the case may be.