diff --git a/Dockerfiles/syncthing/Dockerfile b/Dockerfiles/syncthing/Dockerfile
index 5c7fda6..dde5fd4 100644
--- a/Dockerfiles/syncthing/Dockerfile
+++ b/Dockerfiles/syncthing/Dockerfile
@@ -1,11 +1,12 @@
 FROM buildpack-deps:xenial-curl
 MAINTAINER Kelvin Chen <kelvin@kelvinchen.org>
 
-RUN curl -sL https://syncthing.net/release-key.txt | apt-key add - \
+RUN apt-get update \
+    && apt-get install -y apt-transport-https \
+    && curl -sL https://syncthing.net/release-key.txt | apt-key add - \
     && echo "deb https://apt.syncthing.net/ syncthing release" >> \
         /etc/apt/sources.list.d/syncthing.list \
     && apt-get update \
-    && apt-get install -y apt-transport-https \
     && apt-get install -y syncthing \
     && apt-get clean \
     && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*