diff --git a/dockerfile b/dockerfile
index 82b9f01..390f45d 100644
--- a/dockerfile
+++ b/dockerfile
@@ -9,7 +9,7 @@ ENV ASPNETCORE_URLS=http://+:5000
 RUN adduser -u 5678 --disabled-password --gecos "" appuser && chown -R appuser /app
 USER appuser
 
-FROM mcr.microsoft.com/dotnet/sdk:8.0.101 AS build
+FROM mcr.microsoft.com/dotnet/sdk:9.0.101 AS build
 ARG configuration=Release
 WORKDIR /src
 COPY ["myfunc.csproj", "./"]