I don't get why this is called simple. it's way overblown for a simple repo hosting tool. I serve static Debian packages on my github pages. it's just a matter to create the meta data and upload it to your static space. no need for another http/htps service.
aptly e.g. is much simpler providing the tools to create the meta files for an apt repo, but it can be made much simpler than that. just haven't found it yet.
original author here, maybe giving some background will help explain why this was created (maybe it won't).
at a previous company we were doing the whole micro-services thing + CI/CD and all of the fun that comes with it. every time a service was compiled (dev, test and prod), a deb package was also created as that is how we did deployments. with many services being built on a fairly frequent basis, we ran into an issue using another setup that used s3 as the backing storage (sorry, i don't remember the name) where we were getting race conditions with regards to the repo metadata. that caused all sorts of fun issues during deployments. additionally, the uploading of packages via our build system was a bit clunky.
when i originally wrote this to solve our problems it really was pretty simple, just under 300 lines of actual code and was designed to "solve" the race condition caused by frequent uploads of multiple different packages AND expose the service as a rest endpoint which fit into our build system better.
since i originally wrote deb-simple a few people have come through and submitted AWESOME changes that have made deb-simple a bit more robust without impacting the overall functionality. some of those changes have made deb-simple a bit less... simple, but the trade-off has been well worth it :)