I know it probably doesn't matter too much for internal use, but what does Lintian say about your packages?
Many bad things! I didn't check until now but it's a bunch of "non-standard-dir-perm" and "dir-or-file-in-var-www" and things like "maintainer-name-missing". I think it's possible to build correct debian package with FPM but for our use, we just want to build easily native deb package.
> I think it's possible to build correct debian package with FPM [...]
Of course it is possible, it's just ridiculous amount of work. It's much easier to build package with proper tools in the first place.
This works well but the s3+cron part is probably not the smartest way and publication can take some time (like 5-10min).