If you're interested in working on database internals, it's worth looking at startups—even if you don't have prior experience in this exact area. At my company,

If you're interested in working on database internals, it's worth looking at startups—even if you don't have prior experience in this exact area. At my company, we hire engineers with strong systems backgrounds who haven't necessarily worked on databases before. If that sounds like you, feel free to check my profile for more details.