libebackend1.2-dev 3.50.0-1 (amd64 binary) in ubuntu mantic

 This package contains header files and static library for libebackend.
 .
 libebackend is a utility library for evolution-data-server providing
 backend function to access data.
 .
 Evolution is the integrated mail, calendar, task and address book
 distributed suite from Novell, Inc.