diff --git a/attn/meson.build b/attn/meson.build
index 6a81213..40a3875 100644
--- a/attn/meson.build
+++ b/attn/meson.build
@@ -39,7 +39,8 @@
 
 # gather attention sources to be used here and elsewhere if needed
 attn_src = files('attn_main.cpp', 'attn_handler.cpp', 'attn_monitor.cpp',
-                 'bp_handler.cpp', 'ti_handler.cpp', logging_src)
+                 'bp_handler.cpp', 'ti_handler.cpp', logging_src,
+                 'attention.cpp')
 
 # Create attention handler library
 attn = static_library('attn_handler',