diff --git a/docker/Dockerfile b/docker/Dockerfile
index 7a8d980..506789a 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -1,5 +1,5 @@
 FROM alpine:3.18
-LABEL org.opencontainers.image.source https://github.com/openzim/kiwix-tools
+LABEL org.opencontainers.image.source=https://github.com/openzim/kiwix-tools
 
 # TARGETPLATFORM is injected by docker build
 ARG TARGETPLATFORM