I'm all for promoting own solutions if it fits the context but OP is asking for self-hosted alternatives and this is not. This fits the definition of spam.
Tbf, the OP explicitly said "Preferably self-hosted" which is why I wanted to offer this along with the explicit disclaimer that I am the founder
Just stop, you are spamming on an unrelated post and now arguing about it. I’m sure people will want to sign up for your service now.