diff --git a/example/gen/net/poettering/meson.build b/example/gen/net/poettering/meson.build
index a91287e..3aa2a36 100644
--- a/example/gen/net/poettering/meson.build
+++ b/example/gen/net/poettering/meson.build
@@ -2,7 +2,7 @@
 subdir('Calculator')
 generated_others += custom_target(
     'net/poettering/Calculator__markdown'.underscorify(),
-    input: [ '../../../yaml/net/poettering/Calculator.interface.yaml',  ],
+    input: [ '../../../yaml/net/poettering/Calculator.errors.yaml', '../../../yaml/net/poettering/Calculator.interface.yaml',  ],
     output: [ 'Calculator.md' ],
     depend_files: sdbusplusplus_depfiles,
     command: [
diff --git a/tools/sdbus++-gen-meson b/tools/sdbus++-gen-meson
index 2de2032..665c50e 100755
--- a/tools/sdbus++-gen-meson
+++ b/tools/sdbus++-gen-meson
@@ -230,7 +230,7 @@
     # Determine the source files based on the YAMLs present.
     sources=""
     for s in ${interfaces[$1]}; do
-        sources="'${yamldir}/$1.${s}', "
+        sources="${sources}'${yamldir}/$1.${s}', "
     done
 
     # Create the target to generate the interface.md file.