No one, it's just a toy language

I think "toy language" isn't really fair. Toit has been developed for 7 years, some of which with multiple engineers working on it full time. (The blog post says 4 years, but that's just for the v2.0.0 development).

Toit doesn't have a lot of users, but it is used in production (for example by Consibio) and is definitely developed for production environments.