Link to homepage is a very common metadata that we can find in the package build scripts of many distributions. From what I have seen, the rules in nixpkgs are roughly: if the author has specially created a webpage for a software, then it’s the homepage, otherwise homepage is the link to its repository.
However, I found there are some problems with doing this. We often have the need to access the source code repository, but sometimes it is not very straightforward to find the link to the repository from the webpage provided by the author. I sometimes need to be very keen to look for some keywords such as “star”, “contribute”, “submit an issue”, or “development”, or find the GitHub icon in the sidebar. But in fact, when the maintainer builds the package from source, they must know where its repository is. So maybe we can have a better way to differentiate between “link to the software’s home page” and “link to the software’s repository”?
One may be clumsy and not backward compatible idea is: if a software package does not provide a second page to introduce it in addition to its repository, we only write something like meta.repository. If there is, we write meta.homepage in addition to meta.repository.
Edit: I found that there is indeed a downloadPage, but only 400+ packages use it, and the documentation doesn’t say whether to download the source code or download the build artifacts. https://search.nixos.org does not render these links either.