diff --git a/Makefile b/Makefile
index a55761ce..bc21ff4c 100644
--- a/Makefile
+++ b/Makefile
@@ -68,6 +68,16 @@ REGRESS := $(filter-out add_table, $(REGRESS))
 abs_top_builddir = .
 NO_TEMP_INSTALL = yes
 
+# Override with_temp_install for extension testing.
+# This allows spock tests to run without the pg*-090-init_template_fix.diff
+# patch applied to PostgreSQL. Changes from default PGXS with_temp_install:
+# 1. Remove INITDB_TEMPLATE - we don't use a temp install template
+# 2. Use actual bindir/libdir - we use the installed PostgreSQL, not tmp_install
+with_temp_install = \
+	PATH="$(bindir):$(CURDIR):$$PATH" \
+	$(call add_to_path,$(strip $(ld_library_path_var)),$(libdir)) \
+	$(with_temp_install_extra)
+
 # We can't do a normal 'make check' because PGXS doesn't support
 # creating a temp install. We don't want to use a normal PGXS
 # 'installcheck' though, because it's a pain to set up a temp install
diff --git a/patches/17/pg17-090-init_template_fix.diff b/patches/17/pg17-090-init_template_fix.diff
deleted file mode 100644
index ff436756..00000000
--- a/patches/17/pg17-090-init_template_fix.diff
+++ /dev/null
@@ -1,22 +0,0 @@
-diff --git a/src/Makefile.global.in b/src/Makefile.global.in
-index a00c909681..c915f0a226 100644
---- a/src/Makefile.global.in
-+++ b/src/Makefile.global.in
-@@ -409,10 +409,15 @@ ld_library_path_var = LD_LIBRARY_PATH
- # with_temp_install_extra is for individual ports to define if they
- # need something more here. If not defined then the expansion does
- # nothing.
--with_temp_install = \
-+ifdef NO_TEMP_INSTALL
-+with_temp_install =
-+else
-+with_temp_install = INITDB_TEMPLATE='$(abs_top_builddir)'/tmp_install/initdb-template
-+endif
-+
-+with_temp_install += \
- 	PATH="$(abs_top_builddir)/tmp_install$(bindir):$(CURDIR):$$PATH" \
- 	$(call add_to_path,$(strip $(ld_library_path_var)),$(abs_top_builddir)/tmp_install$(libdir)) \
--	INITDB_TEMPLATE='$(abs_top_builddir)'/tmp_install/initdb-template \
- 	$(with_temp_install_extra)
- 
- temp-install: | submake-generated-headers
diff --git a/patches/18/pg18-090-init_template_fix.diff b/patches/18/pg18-090-init_template_fix.diff
deleted file mode 100644
index 912a36b2..00000000
--- a/patches/18/pg18-090-init_template_fix.diff
+++ /dev/null
@@ -1,22 +0,0 @@
-diff --git a/src/Makefile.global.in b/src/Makefile.global.in
-index 8b1b357beaa..227004fcd36 100644
---- a/src/Makefile.global.in
-+++ b/src/Makefile.global.in
-@@ -425,10 +425,15 @@ ld_library_path_var = LD_LIBRARY_PATH
- # with_temp_install_extra is for individual ports to define if they
- # need something more here. If not defined then the expansion does
- # nothing.
--with_temp_install = \
-+ifdef NO_TEMP_INSTALL
-+with_temp_install =
-+else
-+with_temp_install = INITDB_TEMPLATE='$(abs_top_builddir)'/tmp_install/initdb-template
-+endif
-+
-+with_temp_install += \
- 	PATH="$(abs_top_builddir)/tmp_install$(bindir):$(CURDIR):$$PATH" \
- 	$(call add_to_path,$(strip $(ld_library_path_var)),$(abs_top_builddir)/tmp_install$(libdir)) \
--	INITDB_TEMPLATE='$(abs_top_builddir)'/tmp_install/initdb-template \
- 	$(with_temp_install_extra)
- 
- temp-install: | submake-generated-headers