Introduction
Debian is currently collecting buildinfo but they are not very conveniently searchable. Eventually Chris Lamb's buildinfo.debian.net may solve this problem, but in the mean time, I decided to see how practical indexing the full set of buildinfo files is with sqlite.
Hack
First you need a copy of the buildinfo files. This is currently about 2.6G, and unfortunately you need to be a debian developer to fetch it.
$ rsync -avz mirror.ftp-master.debian.org:/srv/ftp-master.debian.org/buildinfo .
Indexing takes about 15 minutes on my 5 year old machine (with an SSD). If you index all dependencies, you get a database of about 4G, probably because of my natural genius for database design. Restricting to debhelper and dh-elpa, it's about 17M.
$ python3 index.py
You need at least
python3-debian
installedNow you can do queries like
$ sqlite3 depends.sqlite "select * from depends where depend='dh-elpa' and depend_version<='0106'"
where 0106 is some adhoc normalization of 1.6
Conclusions
The version number hackery is pretty fragile, but good enough for my current purposes. A more serious limitation is that I don't currently have a nice (and you see how generous my definition of nice is) way of limiting to builds currently available e.g. in Debian unstable.