diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index e542976..99b4420 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -73,8 +73,9 @@ jobs:
 
     - name: Build extension package
       run: |
-        make -j8 PYTHON=$EDBDIR/python3 EDBFLAGS=--no-devmode PG_CONFIG=/usr/bin/pg_config
-        unzip -l postgis--3.4.3.zip
+        mkdir -p target
+        make -j8 PYTHON=$EDBDIR/python3 EDBFLAGS=--no-devmode PG_CONFIG=/usr/bin/pg_config zip
+        unzip -l postgis--*.zip
 
     - name: Install extension package
       run: |
diff --git a/Makefile b/Makefile
index 77947db..46fa9a2 100644
--- a/Makefile
+++ b/Makefile
@@ -15,7 +15,7 @@ include $(MKS)
 $(SQL_BUILD_STAMP): MANIFEST.toml postgis/NEWS Makefile
 	cd postgis && sh autogen.sh
 	cd postgis && ./configure  "--with-pgconfig=$(PG_CONFIG)" --without-raster
-	$(MAKE) -C postgis
-	$(MAKE) -C postgis comments
-	$(MAKE) -C postgis DESTDIR=$(PWD)/build/out PG_CONFIG=$(PG_DIR)/bin/pg_config install
+	env PG_CONFIG=$(PG_CONFIG) $(MAKE) -C postgis
+	env PG_CONFIG=$(PG_CONFIG) $(MAKE) -C postgis comments
+	env PG_CONFIG=$(PG_CONFIG) $(MAKE) -C postgis DESTDIR=$(PWD)/build/out install
 	touch $(SQL_BUILD_STAMP)
diff --git a/exts.mk b/exts.mk
index 777ddc9..dc0a066 100644
--- a/exts.mk
+++ b/exts.mk
@@ -2,11 +2,10 @@ PYTHON ?= python3
 EXT_NAME := $(shell $(PYTHON) -c 'import tomllib; f = tomllib.load(open("MANIFEST.toml", "rb")); print(f["name"])')
 EXT_VERSION := $(shell $(PYTHON) -c 'import tomllib; f = tomllib.load(open("MANIFEST.toml", "rb")); print(f["version"])')
 EDGEQL_SRCS := $(shell $(PYTHON) -c 'import tomllib; f = tomllib.load(open("MANIFEST.toml", "rb")); print(" ".join(f["files"]))')
-SQL_DIR := $(shell $(PYTHON) -c 'import tomllib; f = tomllib.load(open("MANIFEST.toml", "rb")); print(f["postgres_files"])')
 EXT_FNAME := $(EXT_NAME)--$(EXT_VERSION)
 
-.DEFAULT_GOAL := $(EXT_FNAME).zip
-.PHONY: clean install
+.DEFAULT_GOAL := build
+.PHONY: build clean install zip
 
 #
 
@@ -19,24 +18,36 @@ SQL_DEPS := $(call rwildcard,$(SQL_MODULE),*.c *.h *.sql *.control Makefile)
 SQL_BUILD_STAMP := build/.sql_build_stamp
 SQL_INSTALL_STAMP := build/.sql_install_stamp
 EDGEQL_INSTALL_STAMP := build/.edgeql_install_stamp
+INSTALLABLES := MANIFEST.toml
 
 ifeq ($(strip $(WITH_SQL)),yes)
 
+INSTALLABLES += lib/ share/
+
+ifeq ($(origin PG_CONFIG), undefined)
 EDB := $(PYTHON) -m edb.tools $(EDBFLAGS)
 PG_CONFIG := $(shell $(EDB) config --pg-config)
 
+ifeq ($(PG_CONFIG),)
+$(error cannot find pg_config, please set PG_CONFIG explicitly)
+endif
+endif
+
 ifneq ($(strip $(CUSTOM_SQL_BUILD)),1)
 
 $(SQL_BUILD_STAMP): MANIFEST.toml $(SQL_DEPS) $(EXTRA_DEPS) Makefile
-	$(MAKE) -C $(SQL_MODULE) DESTDIR=$(PWD)/build/out PG_CONFIG=$(PG_CONFIG) install
+	env PG_CONFIG=$(PG_CONFIG) $(MAKE) -C $(SQL_MODULE) DESTDIR=$(PWD)/build/out install
 	touch $(SQL_BUILD_STAMP)
 endif
 
 $(SQL_INSTALL_STAMP): $(SQL_BUILD_STAMP)
-	mkdir -p build/$(SQL_DIR)
-	cp -r $(PWD)/build/out/$(shell $(PG_CONFIG) --pkglibdir) build/$(SQL_DIR)/lib
-	cp -r $(PWD)/build/out/$(shell $(PG_CONFIG) --sharedir) build/$(SQL_DIR)/share
-	cp -r build/$(SQL_DIR) build/$(EXT_FNAME)/$(SQL_DIR)
+	rm -rf build/$(EXT_FNAME)/lib
+	mkdir -p build/$(EXT_FNAME)/lib
+	rm -rf build/$(EXT_FNAME)/share/postgresql
+	mkdir -p build/$(EXT_FNAME)/share/postgresql
+	cp -r $(PWD)/build/out/$(shell $(PG_CONFIG) --pkglibdir) build/$(EXT_FNAME)/lib/postgresql
+	cp -r $(PWD)/build/out/$(shell $(PG_CONFIG) --sharedir)/contrib build/$(EXT_FNAME)/share/postgresql/contrib
+	cp -r $(PWD)/build/out/$(shell $(PG_CONFIG) --sharedir)/extension build/$(EXT_FNAME)/share/postgresql/extension
 	touch $(SQL_INSTALL_STAMP)
 else
 $(SQL_INSTALL_STAMP):
@@ -44,6 +55,8 @@ $(SQL_INSTALL_STAMP):
 	touch $(SQL_INSTALL_STAMP)
 endif
 ifeq ($(strip $(WITH_EDGEQL)),yes)
+INSTALLABLES += $(EDGEQL_SRCS) $(EXTRA_FILES)
+
 $(EDGEQL_INSTALL_STAMP): MANIFEST.toml $(EDGEQL_SRCS) $(EXTRA_FILES) Makefile
 	mkdir -p build/$(EXT_FNAME)
 	cp $(EDGEQL_SRCS) build/$(EXT_FNAME)
@@ -56,14 +69,18 @@ EDGEQL:
 	touch $(EDGEQL_INSTALL_STAMP)
 endif
 
-$(EXT_FNAME).zip: $(EDGEQL_INSTALL_STAMP) $(SQL_INSTALL_STAMP)
-	rm -f $(EXT_FNAME).zip
-	cd build/$(EXT_FNAME)/ && zip -r ../../$(EXT_FNAME).zip *
+build: $(EDGEQL_INSTALL_STAMP) $(SQL_INSTALL_STAMP)
 
-install: $(EXT_FNAME).zip
+install: build
 	if [ -z "$(DESTDIR)" ]; then echo "DESTDIR must be set" >&2; exit 1; fi
 	mkdir -p "$(DESTDIR)"
-	cp $(EXT_FNAME).zip "$(DESTDIR)/"
+	cd "build/$(EXT_FNAME)" && cp -r $(INSTALLABLES) "${DESTDIR}/"
+
+$(EXT_FNAME).zip: build
+	rm -f $(EXT_FNAME).zip
+	cd build/$(EXT_FNAME)/ && zip -r ../../$(EXT_FNAME).zip *
+
+zip: $(EXT_FNAME).zip
 
 clean:
 	rm -rf build $(EXT_FNAME).zip