diff --git a/composer.json b/composer.json
index 76accba..cb5c307 100644
--- a/composer.json
+++ b/composer.json
@@ -20,7 +20,8 @@
     },
     "autoload": {
         "psr-4": {
-            "WellRESTed\\" : "src/"
+            "WellRESTed\\": "src/",
+            "Psr\\Http\\ServerMiddleware\\": "src-fig/"
         }
     }
 }
diff --git a/src-fig/DelegateInterface.php b/src-fig/DelegateInterface.php
new file mode 100644
index 0000000..e4c4e46
--- /dev/null
+++ b/src-fig/DelegateInterface.php
@@ -0,0 +1,7 @@
+<?php
+
+namespace Psr\Http\ServerMiddleware;
+
+interface DelegateInterface extends HandleInterface
+{
+}
diff --git a/src-fig/HandleInterface.php b/src-fig/HandleInterface.php
new file mode 100644
index 0000000..0739ced
--- /dev/null
+++ b/src-fig/HandleInterface.php
@@ -0,0 +1,12 @@
+<?php
+
+namespace Psr\Http\ServerMiddleware;
+
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+
+interface HandleInterface
+{
+    public function __invoke(ServerRequestInterface $request): ResponseInterface;
+}
+
diff --git a/src-fig/MiddlewareInterface.php b/src-fig/MiddlewareInterface.php
new file mode 100644
index 0000000..bb2e3cc
--- /dev/null
+++ b/src-fig/MiddlewareInterface.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace Psr\Http\ServerMiddleware;
+
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+
+interface MiddlewareInterface
+{
+    public function process(
+        ServerRequestInterface $request,
+        DelegateInterface $delegate): ResponseInterface;
+}