>>>>> "GPT" == GPT <gptmailinglists@xxxxxxxxx> writes: GPT> Unfortunately, I had not installed the following package: GPT> "postgresql-server-dev-11" GPT> By the way, shouldn't a warning message appear while trying to run: GPT> `PATH=/usr/lib/postgresql/11/bin:$PATH make USE_PGXS=1` GPT> warning the user that some files are missing. It's more reliable to do (if the makefile is correctly written): make USE_PGXS=1 PG_CONFIG=/usr/lib/postgresql/11/bin/pg_config By specifying the pg_config binary explicitly rather than relying on the PATH, you avoid the chance of picking up an incorrect copy by mistake. This is why the standard form for pgxs makefiles has an assignment for PG_CONFIG before the PGXS assignment line; the command-line option overrides it. -- Andrew (irc:RhodiumToad)