diff --git a/src/Registration/Autoloader.php b/src/Registration/Autoloader.php
new file mode 100644
index 0000000..0039e9e
--- /dev/null
+++ b/src/Registration/Autoloader.php
@@ -0,0 +1,39 @@
+<?php
+declare(strict_types=1);
+
+namespace Keruald\OmniTools\Registration;
+
+class Autoloader {
+
+    ///
+    /// PSR-4
+    ///
+
+    public static function registerPSR4 (string $namespace, string $path) : void {
+        spl_autoload_register(function ($class) use ($namespace, $path) {
+            $len = strlen($namespace);
+
+            if (substr($class, 0, $len) === $namespace) {
+                $classPath = Autoloader::getPathFor(substr($class, $len));
+                include $path . '/' . $classPath;
+            }
+        });
+    }
+
+    public static function getPathFor (string $name) : string {
+        return str_replace("\\", "/", $name) . '.php';
+    }
+
+    ///
+    /// Methods to register OmniTools library
+    ///
+
+    public static function selfRegister () : void {
+        self::registerPSR4("Keruald\\OmniTools\\", self::getLibraryPath());
+    }
+
+    public static function getLibraryPath () : string {
+        return dirname(__DIR__);
+    }
+
+}
diff --git a/tests/Registration/AutoloaderTest.php b/tests/Registration/AutoloaderTest.php
new file mode 100644
index 0000000..fd69f7f
--- /dev/null
+++ b/tests/Registration/AutoloaderTest.php
@@ -0,0 +1,61 @@
+<?php
+declare(strict_types=1);
+
+namespace Keruald\OmniTools\Tests\Registration;
+
+use Keruald\OmniTools\Registration\Autoloader;
+use PHPUnit\Framework\TestCase;
+
+use Acme\MockLib\Foo; // a mock class in a mock namespace to test autoload.
+
+class AutoloaderTest extends TestCase {
+
+    ///
+    /// Tests
+    ///
+
+    /**
+     * @dataProvider providePaths
+     */
+    public function testGetPathFor (string $class, string $expected) : void {
+        $this->assertEquals($expected, Autoloader::getPathFor($class));
+    }
+
+    public function testRegisterPSR4 () : void {
+        $class = Foo::class;
+        $this->assertFalse(
+            class_exists($class),
+            "Please reconfigure the test suite not to include the $class class."
+        );
+
+        Autoloader::registerPSR4("Acme\\MockLib\\", __DIR__ . "/MockLib");
+        $this->assertTrue(class_exists($class));
+    }
+
+    public function testGetLibraryPath () : void {
+        $this->assertStringStartsWith(
+            dirname(Autoloader::getLibraryPath()),  // lib is in <root>/src
+            __DIR__                                 // we are in <root>/tests/…
+        );
+    }
+
+    public function testRegister () : void {
+        $count = count(spl_autoload_functions());
+
+        Autoloader::selfRegister();
+
+        $this->assertEquals(++$count, count(spl_autoload_functions()));
+    }
+
+    ///
+    /// Data provider
+    ///
+
+    public function providePaths () : iterable {
+        // Example from PSR-4 canonical document
+        yield ['File_Writer', 'File_Writer.php'];
+        yield ['Response\Status', 'Response/Status.php'];
+        yield ['Request', 'Request.php'];
+    }
+
+}
diff --git a/tests/Registration/MockLib/Foo.php b/tests/Registration/MockLib/Foo.php
new file mode 100644
index 0000000..cd1b3fa
--- /dev/null
+++ b/tests/Registration/MockLib/Foo.php
@@ -0,0 +1,15 @@
+<?php
+
+namespace Acme\MockLib;
+
+/**
+ * Class Foo
+ *
+ * This class allows to check if the autoloader can register
+ * the Acme\MockLib namespace and include this file.
+ *
+ * @package Acme\MockLib
+ */
+class Foo {
+
+}