postgresql-server-dev-9.4 9.4~rc1-1~0ubuntu0.14.10 (armhf binary) in ubuntu utopic

 Header files for compiling SSI code to link into PostgreSQL's backend; for
 example, for C functions to be called from SQL.
 .
 This package also contains the Makefiles necessary for building add-on
 modules of PostgreSQL, which would otherwise have to be built in the
 PostgreSQL source-code tree.
 .
 PostgreSQL is an object-relational SQL database management system.