If it's a small company, it means you'll be hands on, but also expected to work very, very hard. Compensation is directly linked to how well your code performs, this is especially true if you're in a latency-sensitive environment, like market making / HFT.
However, these jobs tend to only existing in a few locations in the world (Chicago, Boston, NY, London, Hong Kong, Singapore, and maybe a few other places), and they're rarely advertised via normal channels. You're gonna have to make best friends with some actually competent recruiters and get on their short-list, and wait for a call.
Alternative might be to look at crypto trading startups. There are a few well-funded crypto "hedge funds" out there that are attempting to develop market making strategies in that space. You may also find that a lot of exchanges, big and small, have semi-secret market making offshoots that do a lot of prop trading on their exchanges, both to keep the order books full, and to skim profits.
Sports betting is the same, a lot of market makers in that domain are secretly owned by the same people that run the exchanges.