Request: PostgreSQL database backend
... or any memory savvyy database.
Long time ago (StatusNet 0.9.*?), it was possible to use it with a PostgreSQL database. Unfortunately, support has been dropped.
Request is to re-add support for it and make migration scripts from MySQL to PostgreSQL.
Conversion documentation: https://wiki.postgresql.org/wiki/Converting_from_other_Databases_to_PostgreSQL#MySQL