diff --git a/docker/Dockerfile b/docker/Dockerfile
index b24d953349ece26fc02f1696921e690da6b756c1..aa49422db45e8905e8ae5268f3c50cd8fe070e0d 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -84,10 +84,11 @@ LABEL maintainer="Gilles Filippini <gilles.filippini@pini.fr>"
 LABEL version="0.0.0"
 LABEL description="Crypto-currency software (based on Substrate framework) to operate Äž1 libre currency"
 
+# Required certificates for RPC connections
 RUN apt-get update \
  && apt-get install -y --no-install-recommends ca-certificates
-
 RUN update-ca-certificates
+RUN apt-get clean && rm -rf /var/lib/apt/lists/*
 
 RUN adduser --home /var/lib/duniter duniter