diff --git a/push/include/prometheus/gateway.h b/push/include/prometheus/gateway.h
index 577bfa3d..53cfc648 100644
--- a/push/include/prometheus/gateway.h
+++ b/push/include/prometheus/gateway.h
@@ -25,21 +25,15 @@ class Gateway {
 
   static const Labels GetInstanceLabel(std::string hostname);
 
-  enum class HttpMethod {
-    Post,
-    Put,
-    Delete,
-  };
-
   // Push metrics to the given pushgateway.
-  int Push() { return push(HttpMethod::Post); }
+  int Push();
 
-  std::future<int> AsyncPush() { return async_push(HttpMethod::Post); }
+  std::future<int> AsyncPush();
 
   // PushAdd metrics to the given pushgateway.
-  int PushAdd() { return push(HttpMethod::Put); }
+  int PushAdd();
 
-  std::future<int> AsyncPushAdd() { return async_push(HttpMethod::Put); }
+  std::future<int> AsyncPushAdd();
 
   // Delete metrics from the given pushgateway.
   int Delete();
@@ -57,6 +51,12 @@ class Gateway {
 
   std::string getUri(const CollectableEntry& collectable) const;
 
+  enum class HttpMethod {
+    Post,
+    Put,
+    Delete,
+  };
+
   int performHttpRequest(HttpMethod method, const std::string& uri,
                          const std::string& body) const;
 
diff --git a/push/src/gateway.cc b/push/src/gateway.cc
index 84ffd438..59680daa 100644
--- a/push/src/gateway.cc
+++ b/push/src/gateway.cc
@@ -121,6 +121,10 @@ std::string Gateway::getUri(const CollectableEntry& collectable) const {
   return uri.str();
 }
 
+int Gateway::Push() { return push(HttpMethod::Post); }
+
+int Gateway::PushAdd() { return push(HttpMethod::Put); }
+
 int Gateway::push(HttpMethod method) {
   const auto serializer = TextSerializer{};
 
@@ -143,6 +147,10 @@ int Gateway::push(HttpMethod method) {
   return 200;
 }
 
+std::future<int> Gateway::AsyncPush() { return async_push(HttpMethod::Post); }
+
+std::future<int> Gateway::AsyncPushAdd() { return async_push(HttpMethod::Put); }
+
 std::future<int> Gateway::async_push(HttpMethod method) {
   const auto serializer = TextSerializer{};
   std::vector<std::future<int>> futures;