On Software: Open Source Licenses

Posted 2025-06-22

I mostly prefer permissive open source licenses that allow a lot but don’t restrict (or demand) much.
But this may also change, depending on specific projects and/or use cases…

Licenses often used by me

MIT License (MIT)

Very permissive, but has an attribution¹ clause that is phrased a bit vaguely:

… shall be included in all copies or substantial portions of the Software.

What counts as a copy of “the Software”? Only the source code? Or the machine-executable/binary artifacts too?
What is a “substantial portion”?

The BSL-1.0 is more specific in that regard.

MIT No Attribution License (MIT-0)

Like the original MIT license, but without an attribution requirement; i.e. one doesn’t have to name, deliver or display the copyright notice or license terms of the original material.
Makes it basically public domain².

BSD Zero Clause License (0BSD)

Similar to MIT-0: No attribution required.
Puts it also basically into public domain² .

Boost Software License (BSL-1.0)

Similarly permissive as MIT etc., but without attribution requirements in binary-only distributions.
May thus be a good compromise between MIT and MIT-0/0BSD.

Licenses often used by me

Further reading