diff --git a/bin/config.dart b/bin/config.dart
index 2ae6021..f710b40 100644
--- a/bin/config.dart
+++ b/bin/config.dart
@@ -1,5 +1,7 @@
 import 'dart:convert';
 
+import 'dart:io';
+
 class HostAndPort {
   String host;
   int port;
@@ -23,3 +25,11 @@ class ProxyConfig {
 ProxyConfig parseProxyConfig(String config) {
   final jsonConfig = json.decode(config);
 }
+
+Future<ProxyConfig> loadProxyConfig(String configFile/*, {List<String> files} ?? */) async {
+  final configFn = File(configFile);
+  if (!await configFn.exists()) {
+    throw 'Config file not found: ' + configFile;
+  }
+  return parseProxyConfig(await configFn.readAsString());
+}