--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -1,3 +1,5 @@
+include $(TOPDIR)/rules.mk
+
 pcfiles = libseafile.pc
 pkgconfig_DATA = $(pcfiles)
 pkgconfigdir = $(libdir)/pkgconfig
@@ -33,7 +35,7 @@ seafile_HEADERS = seafile-object.h
 
 seafile-object.h: ${seafile_object_define}
 	rm -f $@
-	valac --pkg posix ${seafile_object_define} -C -H seafile-object.h
+	"$(STAGING_DIR_HOSTPKG)/bin/valac" --pkg posix ${seafile_object_define} -C -H seafile-object.h
 
 DISTCLEANFILES = ${searpc_gen}
 
@@ -56,7 +58,7 @@ rpc_table.stamp: ${top_srcdir}/lib/rpc_table.py
 	@rm -f rpc_table.tmp
 	@touch rpc_table.tmp
 	@echo "[libsearpc]: generating rpc header files"
-	@PYTHON@ `which searpc-codegen.py` ${top_srcdir}/lib/rpc_table.py
+	@PYTHON@ "$(STAGING_DIR)/usr/bin/searpc-codegen.py" ${top_srcdir}/lib/rpc_table.py
 	@echo "[libsearpc]: done"
 	@mv -f rpc_table.tmp $@
 
@@ -66,7 +68,7 @@ vala.stamp: ${seafile_object_define}
 	rm -f ${seafile_object_gen}
 	@rm -f vala.tmp
 	@touch vala.tmp
-	valac -C --pkg posix $^
+	"$(STAGING_DIR_HOSTPKG)/bin/valac" -C --pkg posix $^
 	@mv -f vala.tmp $@
 
 ${seafile_object_gen}: vala.stamp
@@ -82,5 +84,5 @@ install-data-local:
 if MACOS
 	sed -i '' -e "s|(DESTDIR)|${DESTDIR}|g" $(pcfiles)
 else
-	${SED} -i "s|(DESTDIR)|${DESTDIR}|g" $(pcfiles)
+	${SED} "s|(DESTDIR)|${DESTDIR}|g" $(pcfiles)
 endif