diff --git a/meson.build b/meson.build
index a93cdd2..565b534 100644
--- a/meson.build
+++ b/meson.build
@@ -60,7 +60,10 @@
 ssl_dep = dependency('openssl')
 
 systemd = dependency('systemd')
-systemd_system_unit_dir = systemd.get_variable('systemd_system_unit_dir')
+systemd_system_unit_dir = systemd.get_variable(
+    'systemd_system_unit_dir',
+    pkgconfig_define: ['prefix', get_option('prefix')],
+)
 
 build_tests = get_option('tests')