postgresql-server-dev-9.6 9.6.8-0ubuntu0.17.10 (s390x binary) in ubuntu artful

 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.