It's the fault of built systems. CMake still doesn't support `import std` officially and undocumented things are done in the ecosystem [1]

But once it works and you setup the new stuff, having started a new CPP26 Project with modules now, it's kinda awesome. I'm certainly never going back. The big compilers are also retroactively adding `import std` to CPP20, so support is widening.

[1] https://gitlab.kitware.com/cmake/cmake/-/work_items/27706

You're not supposed to distribute the precompiled module file. You are supposed to distribute the source code of the module.

Header-only projects are the best to convert to modules because you can put the implementation of a module in a "private module fragment" in that same file and make it invisible to users.

That prevents the compile-time bloat many header-only dependencies add. It also avoids distributing a `.cpp` file that has to be compiled and linked separately, which is why so many projects are header-only.