diff --git a/Dockerfile b/Dockerfile
index 15a93b1..0bea457 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -10,5 +10,5 @@ RUN apk add --no-cache binutils rpm2cpio bash fuse wget patch file desktop-file-
     chmod +x appimagetool-x86_64.AppImage runtime-x86_64 && \
     mkdir /input /output /cache
 VOLUME /input /output /cache
-ENV PATH $PATH:/appimage-builder/src
+ENV PATH=$PATH:/appimage-builder/src
 ENTRYPOINT ["build"]