Ask HN: Non-internal tech recruiters with former tech background...your story?

For those that have a mostly software engineering or other tech job background, any of you out there ever worked as a third party tech recruiter?

A lot of third party recruiters generally come from a sales background and don't necessarily have expertise in the jobs they are helping hire for, but I want to see if there's another side to this. Like software engineers becoming recruiters at a third party agency hiring for software engineering jobs. What's your story? How did you decide to get into tech recruitment?