I don’t understand why not having an (independent, formal) specification is considered unusual for a new language.
It is pretty much impossible to create a nontrivial and novel language with a finalized spec. Either it is going to be super-simple like Scheme, a \epsilon improvement on an existing language, or take 15–20 years until someone bothers to do an official spec (eg C or Common Lisp).
When done too early, all specifications do is tie down the best minds working on the language for years, essentially stalling all development.