diff --git a/Dockerfile b/Dockerfile
index 52bfca3007c12706c42faf203233aea68a3321b1..69d9f7966654e5322cce83afdf8610e690bf35e0 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,7 +3,7 @@ FROM registry.git.autistici.org/ai3/docker/s6-base:master
 RUN apt-get -q update && \
     env DEBIAN_FRONTEND=noninteractive apt-get -qy install --no-install-recommends \
         python3-flask python3-sqlalchemy python3-flask-sqlalchemy python3-flask-script \
-        python3-setuptools
+        python3-setuptools ca-certificates
 
 ADD . /tmp/src
 WORKDIR /tmp/src