diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index de0a5bb..86f2411 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -37,6 +37,7 @@ freebsd-cross-build:
     - apk add git
     - git clone https://github.com/wezm/freebsd-cross-build.git
     - cd freebsd-cross-build
+    - echo "RUN apt-get update && apt-get install -y git" >> Dockerfile
     - VERSION=$(git rev-parse --short=8 HEAD)
     - docker login -u gitlab-ci-token -p ${CI_JOB_TOKEN} ${CI_REGISTRY}
     - docker build -t ${CI_REGISTRY_IMAGE}/${CI_JOB_NAME}:${VERSION} .
diff --git a/signald-builder.Dockerfile b/signald-builder.Dockerfile
index 492b374..f4907ed 100644
--- a/signald-builder.Dockerfile
+++ b/signald-builder.Dockerfile
@@ -1,4 +1,6 @@
 FROM debian:latest
+RUN dpkg --add-architecture armhf && dpkg --add-architecture arm64
+ADD apt-signing-key.asc /tmp/apt-signing-key.asc
 RUN apt-get update && apt-get install -y \
   gpg \
   dpkg-dev \
@@ -13,11 +15,15 @@ RUN apt-get update && apt-get install -y \
   gradle-debian-helper \
   jq \
   aptly \
+  build-essential \
+  crossbuild-essential-armhf \
+  crossbuild-essential-arm64 \
   && rm -rf /var/lib/apt/lists/*
-RUN adduser signald
+
 COPY deb-scripts/release-deb.sh /usr/bin/release-deb
 COPY deb-scripts/get-component.sh /usr/bin/get-component
 COPY deb-scripts/repo-cron.sh /usr/bin/repo-cron
+
+RUN adduser signald
 USER signald
-ADD apt-signing-key.asc /tmp/apt-signing-key.asc
 RUN gpg --no-default-keyring --keyring trustedkeys.gpg --import /tmp/apt-signing-key.asc