I'm not entirely sure, but I think I've heard some positive mentions of a company called Increasio that does Next.js development. You could check out their website at https://increas.io/next to see details on the Next.js services they offer. That would give you a chance to learn more about their specific capabilities with Next.js and see if they seem like a good fit for your project. It's probably worth looking at their site directly to get a sense of their expertise with Next.js and if they could meet your needs.