diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index c9808b9..e2689e8 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -72,7 +72,7 @@ jobs:
         run: make install USE_PGXS=1
         working-directory: ptrack
       - name: Install Pg_probackup
-        run: make install-pg-probackup
+        run: make install-pg-probackup USE_PGXS=1 PG_CONFIG=$PREFIX/bin/pg_config top_srcdir=../postgres
         working-directory: ptrack
       # The sources are checked out by the root but ptrack tests need to write
       # to the source tree
diff --git a/Makefile b/Makefile
index 6e838f4..e706c2f 100644
--- a/Makefile
+++ b/Makefile
@@ -49,8 +49,7 @@ install-postgres:
 	$(MAKE) -s -j $(nproc) install && \
 	$(MAKE) -s -j $(nproc) -C contrib/ install
 
-# Now when Postgres is built we can use PGXS for all remainig targets
-USE_PGXS = 1
+# Now when Postgres is built call all remainig targets with USE_PGXS=1
 
 test-tap:
 ifeq ($(TEST_MODE), legacy)
@@ -60,8 +59,10 @@ else
 endif
 
 pg_probackup_dir ?= $(CURDIR)/../pg_probackup
+# Pg_probackup's Makefile uses top_srcdir when building via PGXS so set it when calling this target
 install-pg-probackup:
-	$(MAKE) -j $(nproc) -C $(pg_probackup_dir) install
+	echo PATH=$PATH
+	$(MAKE) -j $(nproc) -C $(pg_probackup_dir) install USE_PGXS=$(USE_PGXS) PG_CONFIG=$(PG_CONFIG) top_srcdir=$(top_srcdir)
 
 test-python:
 	env=PG_PROBACKUP_PTRACK=ON; \