I would encourage you not to use DOIs for software. They are not made for this, and have limitations which are not appropriate.
Instead, use Software Heritage https://www.softwareheritage.org/ , it provides unique identifiers and actually understand repositories, versioning, history, etc.
It also allows you to cite the software and even give proper, durable links to point to the code.
Instead, use Software Heritage https://www.softwareheritage.org/ , it provides unique identifiers and actually understand repositories, versioning, history, etc. It also allows you to cite the software and even give proper, durable links to point to the code.