diff --git a/tcp/Dockerfile b/tcp/Dockerfile
index dfd8bbc..8d91a3a 100644
--- a/tcp/Dockerfile
+++ b/tcp/Dockerfile
@@ -1,5 +1,5 @@
 # syntax=docker/dockerfile:1.5
-FROM golang:1.20-alpine as builder
+FROM golang:1.21-alpine as builder
 
 WORKDIR /go/src/github.com/nginxinc/kic-test-containers/
 COPY tcp/main.go ./tcp/