diff --git a/docker/cluster/Dockerfile b/docker/cluster/Dockerfile
index 75519b4..93a1ad0 100644
--- a/docker/cluster/Dockerfile
+++ b/docker/cluster/Dockerfile
@@ -1,4 +1,4 @@
-FROM rust:1.76 as builder
+FROM rust:1.91 as builder
 WORKDIR /app
 
 # Copy workspace manifests first for caching.