diff --git a/lib/server.js b/lib/server.js
index 631640b..c4668bf 100644
--- a/lib/server.js
+++ b/lib/server.js
@@ -23,12 +23,31 @@ colors.setTheme({
   error: 'red'
 });
 
-// Default initialized options.
-var options = {
-  key: fs.readFileSync(__dirname + '/../keys/key.pem'),
-  cert: fs.readFileSync(__dirname + '/../keys/crt.pem'),
-  port: 55073
-};
+// Parse command-line arguments.
+var options = require('optimist')
+              .options({
+                port: {
+                  demand: true,
+                  alias: 'p',
+                  description: 'Listen port',
+                  default: 55073
+                },
+                keyPath: {
+                  demand: true,
+                  alias: 'k',
+                  description: 'SSL key path',
+                  default: __dirname + '/../keys/key.pem',
+                },
+                certPath: {
+                  demand: true,
+                  alias: 'c',
+                  description: 'SSL certificate path',
+                  default: __dirname + '/../keys/crt.pem',
+                }
+              }).argv;
+
+options.key = fs.readFileSync(options.keyPath);
+options.cert = fs.readFileSync(options.certPath);
 
 // Shortens the given URL to given maxLen by inserting '...'.
 function shortenUrl(url, maxLen) {
diff --git a/package.json b/package.json
index f8d3054..2fda1fb 100644
--- a/package.json
+++ b/package.json
@@ -20,6 +20,7 @@
     "spdy": "~1.26.0",
     "colors": "~0.6.2",
     "memory-cache": "0.0.5",
-    "png": "~3.0.3"
+    "png": "~3.0.3",
+    "optimist": "~0.6.1"
   }
 }