diff --git a/Dockerfile b/Dockerfile
index 2da3a46..6c04f67 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -37,6 +37,7 @@ RUN set -eux; \
     rustup --version; \
     cargo --version; \
     rustc --version; \
+    rustup toolchain list; \
     \
     apt remove -y --auto-remove \
         ### ditch the wget who needs that