Hello Manticore team's member here.
Vasyl Gello asked me to step in. Just few notes: 1) On behalf of Manticore team I can assure we can help with pushing and maintaining Manticore's packages for Debian. We have build procedures for Debian 8/9/10 as well as and CI and pre-release production testing and make regular releases (about each 2 months). 2) There's no source available publicly for Sphinx 3.* while Manticore Search's source is available on https://github.com/manticoresoftware/manticoresearch Best wishes, Sergey Nikolaev