diff --git a/tests/Dockerfile b/tests/Dockerfile
index 5dc158a136..6e3899393e 100644
--- a/tests/Dockerfile
+++ b/tests/Dockerfile
@@ -1,4 +1,4 @@
-# syntax=docker/dockerfile:1.19
+# syntax=docker/dockerfile:1.20
 FROM python:3.14-trixie@sha256:d88b1201e20b36976ff9d779cf1705cfa3598540a81bc31f0eee70a1e1f318e3