diff --git a/Dockerfile b/Dockerfile
index dfd7ce6..83b0b6e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM golang:1.19-buster as builder
+FROM golang:1.19-buster@sha256:46bab7f043402231a9ed12ef2a4b0a9d090e3abc005297de920160a76bc71da3 as builder
 
 WORKDIR /src
 
@@ -8,7 +8,7 @@ RUN go install -v github.com/prometheus/promu \
     && promu build -v --prefix build
 
 
-FROM debian:buster-slim
+FROM debian:buster-slim@sha256:bb3dc79fddbca7e8903248ab916bb775c96ec61014b3d02b4f06043b604726dc
 LABEL maintainer="Vasily Maryutenkov <vasily.maryutenkov@flant.com>"
 
 RUN DEBIAN_FRONTEND=noninteractive; apt-get update \