diff --git a/composer.json b/composer.json
index a2df466..8a98cfb 100644
--- a/composer.json
+++ b/composer.json
@@ -48,6 +48,7 @@
             "Shaarli\\Netscape\\": "application/netscape",
             "Shaarli\\Plugin\\": "application/plugin",
             "Shaarli\\Plugin\\Exception\\": "application/plugin/exception",
+            "Shaarli\\Plugin\\Wallabag\\": "plugins/wallabag",
             "Shaarli\\Render\\": "application/render",
             "Shaarli\\Security\\": "application/security",
             "Shaarli\\Updater\\": "application/updater",
diff --git a/plugins/wallabag/WallabagInstance.php b/plugins/wallabag/WallabagInstance.php
index eb8ab61..f4a0a92 100644
--- a/plugins/wallabag/WallabagInstance.php
+++ b/plugins/wallabag/WallabagInstance.php
@@ -1,4 +1,5 @@
 <?php
+namespace Shaarli\Plugin\Wallabag;
 
 /**
  * Class WallabagInstance.
diff --git a/plugins/wallabag/wallabag.php b/plugins/wallabag/wallabag.php
index 5ba1611..bc35df0 100644
--- a/plugins/wallabag/wallabag.php
+++ b/plugins/wallabag/wallabag.php
@@ -1,12 +1,11 @@
 <?php
-
 /**
- * Plugin Wallabag.
+ * Wallabag plugin
  */
 
-require_once 'WallabagInstance.php';
 use Shaarli\Config\ConfigManager;
 use Shaarli\Plugin\PluginManager;
+use Shaarli\Plugin\Wallabag\WallabagInstance;
 
 /**
  * Init function, return an error if the server is not set.
diff --git a/tests/plugins/PluginAddlinkTest.php b/tests/plugins/PluginAddlinkTest.php
index e0a0107..d052f8b 100644
--- a/tests/plugins/PluginAddlinkTest.php
+++ b/tests/plugins/PluginAddlinkTest.php
@@ -1,4 +1,5 @@
 <?php
+namespace Shaarli\Plugin\Addlink;
 
 use Shaarli\Plugin\PluginManager;
 use Shaarli\Router;
diff --git a/tests/plugins/PluginArchiveorgTest.php b/tests/plugins/PluginArchiveorgTest.php
index d06bfa5..510288b 100644
--- a/tests/plugins/PluginArchiveorgTest.php
+++ b/tests/plugins/PluginArchiveorgTest.php
@@ -1,4 +1,5 @@
 <?php
+namespace Shaarli\Plugin\Archiveorg;
 
 /**
  * PluginArchiveorgTest.php
@@ -12,7 +13,7 @@ require_once 'plugins/archiveorg/archiveorg.php';
  * Class PluginArchiveorgTest
  * Unit test for the archiveorg plugin
  */
-class PluginArchiveorgTest extends PHPUnit_Framework_TestCase
+class PluginArchiveorgTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Reset plugin path
diff --git a/tests/plugins/PluginIssoTest.php b/tests/plugins/PluginIssoTest.php
index 7aee219..bdfab43 100644
--- a/tests/plugins/PluginIssoTest.php
+++ b/tests/plugins/PluginIssoTest.php
@@ -1,5 +1,7 @@
 <?php
+namespace Shaarli\Plugin\Isso;
 
+use DateTime;
 use Shaarli\Bookmark\LinkDB;
 use Shaarli\Config\ConfigManager;
 use Shaarli\Plugin\PluginManager;
@@ -11,7 +13,7 @@ require_once 'plugins/isso/isso.php';
  *
  * Test the Isso plugin (comment system).
  */
-class PluginIssoTest extends PHPUnit_Framework_TestCase
+class PluginIssoTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Reset plugin path
diff --git a/tests/plugins/PluginMarkdownTest.php b/tests/plugins/PluginMarkdownTest.php
index 90a19e7..5e7c02b 100644
--- a/tests/plugins/PluginMarkdownTest.php
+++ b/tests/plugins/PluginMarkdownTest.php
@@ -1,4 +1,6 @@
 <?php
+namespace Shaarli\Plugin\Markdown;
+
 use Shaarli\Config\ConfigManager;
 use Shaarli\Plugin\PluginManager;
 
@@ -14,7 +16,7 @@ require_once 'plugins/markdown/markdown.php';
  * Class PluginMarkdownTest
  * Unit test for the Markdown plugin
  */
-class PluginMarkdownTest extends PHPUnit_Framework_TestCase
+class PluginMarkdownTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * @var ConfigManager instance.
diff --git a/tests/plugins/PluginPlayvideosTest.php b/tests/plugins/PluginPlayvideosTest.php
index aa3ad14..5147261 100644
--- a/tests/plugins/PluginPlayvideosTest.php
+++ b/tests/plugins/PluginPlayvideosTest.php
@@ -1,4 +1,5 @@
 <?php
+namespace Shaarli\Plugin\Playvideos;
 
 /**
  * PluginPlayvideosTest.php
@@ -8,13 +9,12 @@ use Shaarli\Plugin\PluginManager;
 use Shaarli\Router;
 
 require_once 'plugins/playvideos/playvideos.php';
-require_once 'application/Router.php';
 
 /**
  * Class PluginPlayvideosTest
  * Unit test for the PlayVideos plugin
  */
-class PluginPlayvideosTest extends PHPUnit_Framework_TestCase
+class PluginPlayvideosTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Reset plugin path
diff --git a/tests/plugins/PluginPubsubhubbubTest.php b/tests/plugins/PluginPubsubhubbubTest.php
index 4680513..a7bd8fc 100644
--- a/tests/plugins/PluginPubsubhubbubTest.php
+++ b/tests/plugins/PluginPubsubhubbubTest.php
@@ -1,16 +1,17 @@
 <?php
+namespace Shaarli\Plugin\Pubsubhubbub;
+
 use Shaarli\Config\ConfigManager;
 use Shaarli\Plugin\PluginManager;
 use Shaarli\Router;
 
 require_once 'plugins/pubsubhubbub/pubsubhubbub.php';
-require_once 'application/Router.php';
 
 /**
  * Class PluginPubsubhubbubTest
  * Unit test for the pubsubhubbub plugin
  */
-class PluginPubsubhubbubTest extends PHPUnit_Framework_TestCase
+class PluginPubsubhubbubTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * @var string Config file path (without extension).
diff --git a/tests/plugins/PluginQrcodeTest.php b/tests/plugins/PluginQrcodeTest.php
index 325e310..0c61e14 100644
--- a/tests/plugins/PluginQrcodeTest.php
+++ b/tests/plugins/PluginQrcodeTest.php
@@ -1,4 +1,6 @@
 <?php
+namespace Shaarli\Plugin\Qrcode;
+
 /**
  * PluginQrcodeTest.php
  */
@@ -7,13 +9,12 @@ use Shaarli\Plugin\PluginManager;
 use Shaarli\Router;
 
 require_once 'plugins/qrcode/qrcode.php';
-require_once 'application/Router.php';
 
 /**
  * Class PluginQrcodeTest
  * Unit test for the QR-Code plugin
  */
-class PluginQrcodeTest extends PHPUnit_Framework_TestCase
+class PluginQrcodeTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Reset plugin path
diff --git a/tests/plugins/PluginWallabagTest.php b/tests/plugins/PluginWallabagTest.php
index 4e445ef..7975192 100644
--- a/tests/plugins/PluginWallabagTest.php
+++ b/tests/plugins/PluginWallabagTest.php
@@ -1,11 +1,9 @@
 <?php
+namespace Shaarli\Plugin\Wallabag;
+
 use Shaarli\Config\ConfigManager;
 use Shaarli\Plugin\PluginManager;
 
-/**
- * PluginWallabagTest.php.php
- */
-
 require_once 'plugins/wallabag/wallabag.php';
 
 /**
diff --git a/tests/plugins/WallabagInstanceTest.php b/tests/plugins/WallabagInstanceTest.php
index 2c46687..bcc0160 100644
--- a/tests/plugins/WallabagInstanceTest.php
+++ b/tests/plugins/WallabagInstanceTest.php
@@ -1,11 +1,12 @@
 <?php
+namespace Shaarli\Plugin\Wallabag;
 
-require_once 'plugins/wallabag/WallabagInstance.php';
+use Shaarli\Plugin\Wallabag\WallabagInstance;
 
 /**
  * Class WallabagInstanceTest
  */
-class WallabagInstanceTest extends PHPUnit_Framework_TestCase
+class WallabagInstanceTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * @var string wallabag url.