diff --git a/k8s/annorepo-server/Dockerfile-multistage b/k8s/annorepo-server/Dockerfile-multistage
index 43f3e5b8..7f04a43f 100644
--- a/k8s/annorepo-server/Dockerfile-multistage
+++ b/k8s/annorepo-server/Dockerfile-multistage
@@ -9,7 +9,7 @@ COPY ./pom.xml /build/
 COPY ./config.yml config.yml
 RUN mvn --projects server --no-transfer-progress --batch-mode --update-snapshots --also-make package
 
-FROM openjdk:20-rc-jdk-slim
+FROM openjdk:21-rc-jdk-slim
 
 WORKDIR /apps/annorepo
 COPY --from=builder /build/server/target/annorepo-server-*.jar /apps/annorepo/annorepo-server.jar