diff --git a/Dockerfile b/Dockerfile
index c6b834b..a4461f2 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,7 +1,7 @@
 # Dockerfile — shared-sqs multi-stage build
-# Updated: 2026-04-09
+# Updated: 2026-04-12 — Go 1.23 (required by prometheus client)
 
-FROM golang:1.22-alpine AS builder
+FROM golang:1.23-alpine AS builder
 WORKDIR /build
 COPY go.mod go.sum ./
 RUN go mod download