I am converting our current lists class to a proper sympa module, and I am looking at the dependencies we currently setup in puppet vs. the dependencies that the debian package uses so I can move the generica stuff to the module.
Here is a list of common dependencies, dependencies that only riseup has, and depends/recommends/suggests that the debian package has but riseup doesn’t, with notes if we know why or what we plan to do with it. If the depends is versioned, that means the debian package had it versioned (and maybe we should figure out why, maybe it’s important).

Common dependencies

These shouldn’t need much explanation.

libarchive-zip-perl (>= 1.05),
libterm-progressbar-perl,
libmime-encwords-perl,
libcgi-fast-perl, (is pulled in by perl-modules->libcgi-pm-perl anyway)
libfcgi-perl,
perl-modules (>= 5.10) | libcgi-pm-perl (>= 3.35),
libfile-copy-recursive-perl (>= 0.36),
libintl-perl,
mhonarc,
libnet-netmask-perl,
libregexp-common-perl,
libtemplate-perl,
libsoap-lite-perl,
libapache2-mod-fastcgi,
libapache2-mod-fcgid,
libdbd-mysql-perl (>= 4.007),
libmime-charset-perl,
libhtml-stripscripts-parser-perl (>= 1.0),
libmime-lite-html-perl,

Debian Extra

These are things listed by the debian package that we didn’t have in our puppet class. We need to figure out why and fix.

Depends:
 libdbd-pg-perl,      \
 libdbd-sybase-perl,  |  maybe these should be OR'd?
 libdbd-sqlite3-perl, /
 sqlite3,  (if the libdbd is installed, then it's pulling in the right libs, is this needed?)
 libmailtools-perl (>= 1.51), (installed on willet, lots of stuff uses Mail::, we should add)
 libmsgcat-perl (>= 1.0), (maybe not needed? or maybe only needed in build?)
 libmime-tools-perl, (installed on willet, lots of stuff uses MIME::, we should add this)
 libio-stringy-perl, (installed on willet, lots of stuff uses IO::Scalar, we should add this)
 libnet-ldap-perl, (maybe this can be a Suggests? might still be required upstream)
 libxml-libxml-perl, (installed on willet, lots of stuff uses XML::LibXML, we should add this)
 libhtml-tree-perl, (installed on willet, used for plain digests, we should add)
 libhtml-format-perl, (installed on willet, used for plain digests, we should add)
 default-mta | mail-transport-agent, (our module will include a postfix class)
 sysklogd (>= 1.3-27) | system-log-daemon, (I guess our module might include a syslog type?)
 lsb-base, (due to debian init file)
 adduser, (to setup sympa user, our class will do this)
 dbconfig-common, (to setup database, our class won't do this)
 libunicode-linebreak-perl (not installed on willet, things use Text::LineFold, we should add)

Recommends:
 libfile-nfslock-perl, (only needed if you do nfs)
 libio-socket-ssl-perl, (installed on willet, used, we should add)
 libcrypt-ciphersaber-perl, (installed on willet, needed, we should add)
 libmail-dkim-perl (>= 0.36), (not installed on willet, not having it disables some features, we should test and add)
 logrotate, (maybe our module might depend on log rotation?)
 doc-base, (maybe this can be dropped?)
 mysql-server | postgresql, (our module will need a way to depend on a db)
 locales, (installed on willet, we already install elsewhere)
 ca-certificates (installed on willet, we already install elsewhere)

Suggests: libauthcas-perl (>= 1.4), (not installed on willet, a single-sign-on-thing)
 libdbd-oracle-perl (>= 0.90), (in contrib)
 libtext-wrap-perl, (Text::Wrap is in perl-base now, should probably be removed from debian package)
 apache2 | httpd-cgi, (module will have some way to depend)
 openssl (>= 0.9.5a) (hmm, where do we install openssl? add?)

I sent some of these questions to the sympa package maintainers. They replied.

Riseup extra

These are things we had in our puppet class, but aren’t in the debian package. We need to figure out why and fix.

subversion, (we used to use svn to pull some stuff, I think this can go away)
php5-cli, (ecology uses, maybe others?)
gettext, (needed for the build?)
libnet-daemon-perl, (needed by libplrpc-perl, can go away)
libplrpc-perl, (needed by libdbi-perl, can go away)
libapache2-mod-removeip, (riseup specific, should move to site module)
git-core, (we use git to checkout some things)
libemail-valid-perl, (taggart's scripts use this, should move to a subclass)
libdbi-perl, (any of the libdbd-perl* things pull this in, we used to specify a version of this which is probably why its in here, not needed)
spamass-milter, (needed for the milter, should move to a subclass)
libhtml-stripscripts-perl (pulled in by libhtml-stripscripts-parser-perl, not needed)