alt Hacker NewsIt’s open source under the Apache 2 license, not source available.
Accepting contributions is not required to be open source.
SQLite doesn’t accept contributions from random people either [0] (though you could argue being public domain isn’t being open source).
Anyway, this is great, I was waiting for this to take the language for a spin! Congrats to the Mojo team!
[0]: https://simonwillison.net/2025/Dec/29/copyright-release/
Maybe it is not listed by the OSI, but it is 'open source' in practice, if the source is also in the public domain. The FSF's definition of free software makes more sense not only ideologically, but also because it does not try to be exhaustive.