[Philip-J-Fry]

What problems are they? I can't really think of any problems where writing the code was the hard part.

There's plenty of times where I don't know what code to write because I've never used a library before. But it's just a page of documentation away. It's not hard, it's just slow and tedious.

[mountainriver]

Writing machine learning kernels. Writing low level geometry libraries. Writing compilers...