diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 0000000..6e19512
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1,2 @@
+.dockerignore
+Dockerfile
diff --git a/Dockerfile b/Dockerfile
index 6b1b03f..d31de09 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -34,7 +34,7 @@ RUN apt-get update \
   && apt-get install -y dumb-init apache2 $(cat /run.txt) \
   && apt-get clean \
   && rm -rf /var/lib/apt/lists/* /run.txt \
-  && a2enmod rewrite proxy proxy_http
+  && a2enmod rewrite proxy proxy_http ssl
 COPY ./vhost.conf /etc/apache2/sites-available/000-default.conf
 COPY --from=builder /usr/local /usr/local
 
diff --git a/vhost.conf b/vhost.conf
index d295c6c..1838b1f 100644
--- a/vhost.conf
+++ b/vhost.conf
@@ -9,4 +9,5 @@
         RewriteMap preview "prg://usr/local/bin/zuul-preview"
         RewriteRule "^/notfound" "-" [F]
         RewriteRule "^/?(.*)$" "${preview:%{ENV:ZUUL_API_URL} %{HTTP_HOST}|http://localhost/notfound}/$1" [P]
+        SSLProxyEngine on
 </VirtualHost>
diff --git a/zuul-preview/main.cc b/zuul-preview/main.cc
index e5aeff7..5722288 100644
--- a/zuul-preview/main.cc
+++ b/zuul-preview/main.cc
@@ -165,7 +165,7 @@ int main(int, char**)
       auto body = response.extract_json().get();
       auto artifacts = body["artifacts"].as_array();
 
-      string artifact_url = "Artifact_not_found";
+      string artifact_url = "NULL";
       for (uint i = 0; i < artifacts.size(); i++) {
         if (artifacts[i].has_field("metadata") &&
             artifacts[i]["metadata"].has_field("type") &&
@@ -175,6 +175,11 @@ int main(int, char**)
         }
       }
 
+      // The apache config is guaranteed to add a / to this, so avoid
+      // double slashes on the end.
+      if (artifact_url.back() == '/') {
+        artifact_url.pop_back();
+      }
       cout << artifact_url << endl;
 
       cache.put(hostname, artifact_url);