Any advice for a searchable web archiver ?

Hello,

As the sympa community (http://www.sympa.org) recently grown, we are
thinking about revamping the whole UI and we would like to have
a new web archiver based on:

* no default frontend but exposing the API through REST, websockets or
  whatever.
* maximizing the interactions between Sympa and CPAN
* trying to avoid other dynamic langage or jvm dependency
  (or considering them as temporary solutions)
* being JMAP friendly (we bet on it to become a very healthy community)

My first idea was to use notmuch, PEP modules and Dancer on top of
maildirs then i discover Dezi (inactive since 2015) and the use of
Lucy (also used by the very active librecat project).

I know Dezi is a general search engine but i hope that taking care of
a good email support for it than reinvent the wheel.

Those are lot of things to look for if i want to have a clear opinion
on a good strategy. Any advice would be warmly welcome.

thanks in advance,
marc