diff --git a/modules/restricted-guests/synapse/Dockerfile b/modules/restricted-guests/synapse/Dockerfile
index 3941d9511e..baaab8c2ca 100644
--- a/modules/restricted-guests/synapse/Dockerfile
+++ b/modules/restricted-guests/synapse/Dockerfile
@@ -1,6 +1,6 @@
 FROM debian:bookworm-slim
 
 WORKDIR /src
-ADD synapse_guest_module /src/synapse_guest_module
+COPY synapse_guest_module /src/synapse_guest_module
 
 CMD ["cp", "-r", "/src/synapse_guest_module", "/modules"]