diff --git a/attn/meson.build b/attn/meson.build
index b4d2705..c366182 100644
--- a/attn/meson.build
+++ b/attn/meson.build
@@ -6,18 +6,21 @@
 # dependency to link gpiod support
 libgpiod = dependency('libgpiod', version : '>=1.4.1')
 
-# ENABLE_PHAL_TRUE used in attn_handler.service
+# ENABLE_PHAL_TRUE used in attn_handler.service.in
+attn_conf = configuration_data()
+
 if (get_option('phal').enabled())
-    configuration_data().set('ENABLE_PHAL_TRUE', '')
+    attn_conf.set('ENABLE_PHAL_TRUE', '')
 else
-    configuration_data().set('ENABLE_PHAL_TRUE', '#')
+    attn_conf.set('ENABLE_PHAL_TRUE', '#')
 endif
 
 # install systemd unit file
 configure_file(
-    input: 'attn_handler.service',
+    configuration: attn_conf,
+    input: 'attn_handler.service.in',
     output: 'attn_handler.service',
-    copy: true,
+    install: true,
     install_dir:
         dependency('systemd').get_pkgconfig_variable(
             'systemdsystemunitdir')