Comment by ricardo81

I wouldn't hard recommend based on lack of solid experience of using them over time, but Gandi showed a lot of promise for me.

Context: I used to run a domain-related service that used registrar api's and gandi's seemed the most well thought out by a considerable way. The drawback was they're quite expensive for registrations/renewals unless you're doing it at volume.

I had reservations about them being a French company wrt support but their API was so good I never needed to contact them on anything.

Definitely worth a look.