diff --git a/.travis.yml b/.travis.yml
index 434d1af..1f2cff1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,9 +1,15 @@
+sudo: false
+
 language: php
 php:
+  - 5.3
   - 5.4
   - 5.5
+  - 5.6
+  - 7
+  - hhvm
 
 before_script:
  - composer selfupdate --quiet
- - composer install --dev
+ - composer install --prefer-dist
  - vendor/phpunit/phpunit/composer/bin/phpunit
diff --git a/src/JacobKiers/OAuth/SignatureMethod/SignatureMethod.php b/src/JacobKiers/OAuth/SignatureMethod/SignatureMethod.php
index 74a833b..067b5d1 100644
--- a/src/JacobKiers/OAuth/SignatureMethod/SignatureMethod.php
+++ b/src/JacobKiers/OAuth/SignatureMethod/SignatureMethod.php
@@ -27,6 +27,28 @@ use \JacobKiers\OAuth\Request\RequestInterface;
  */
 abstract class SignatureMethod implements SignatureMethodInterface
 {
+    /**
+     * Return the name of the Signature Method (ie HMAC-SHA1).
+     *
+     * @return string
+     */
+    abstract public function getName();
+
+    /**
+     * Build up the signature.
+     *
+     * NOTE: The output of this function MUST NOT be urlencoded.
+     * the encoding is handled in OAuthRequest when the final
+     * request is serialized.
+     *
+     * @param JacobKiers\OAuth\Request\RequestInterface $request
+     * @param JacobKiers\OAuth\Consumer\ConsumerInterface        $consumer
+     * @param JacobKiers\OAuth\Token\TokenInterface     $token
+     *
+     * @return string
+     */
+    abstract public function buildSignature(RequestInterface $request, ConsumerInterface $consumer, TokenInterface $token = null);
+
     /**
      * Get the signature key, made up of consumer and optionally token shared secrets.
      *