diff --git a/README.md b/README.md
deleted file mode 100644
index dcc9bd2..0000000
--- a/README.md
+++ /dev/null
@@ -1,10 +0,0 @@
-# SucklessPHP - Another PHP framework that sucks less
-
-Follow this documentation:
-
-https://gitpull.it/w/suckless-php/
-
-## License
-Copyright (c) 2015-2019 [Valerio Bozzolan](http://boz.reyboz.it/)
-
-This is a **Free** as in **Freedom** project. It comes with ABSOLUTELY NO WARRANTY. You are welcome to redistribute it under the terms of the **GNU General Public License v3+**.
diff --git a/tests/TestFilesystem.php b/phpunit/FilesystemTest.php
similarity index 95%
rename from tests/TestFilesystem.php
rename to phpunit/FilesystemTest.php
index fefd083..695a44a 100644
--- a/tests/TestFilesystem.php
+++ b/phpunit/FilesystemTest.php
@@ -1,60 +1,60 @@
 <?php
 // use the phpunit framework
 use PHPUnit\Framework\TestCase;
 
 /**
  * Test Query class
  */
-final class TestFilesystem extends TestCase {
+final class FilesystemTest extends TestCase {
 
 	/**
 	 * Test the append_dir() function
 	 */
 	public function testAppendDir1() {
 		$this->assertEquals(
 			append_dir( 'asd', 'dsa' ),
 			'asd/dsa'
 		);
 	}
 
 	/**
 	 * Test the append_dir() function
 	 */
 	public function testAppendDir2() {
 		$this->assertEquals(
 			append_dir( 'asd/', 'dsa' ),
 			'asd/dsa'
 		);
 	}
 
 	/**
 	 * Test the append_dir() function
 	 */
 	public function testAppendDir3() {
 		$this->assertEquals(
 			append_dir( 'asd', '/dsa' ),
 			'asd/dsa'
 		);
 	}
 
 	/**
 	 * Test the append_dir() function
 	 */
 	public function testAppendDir4() {
 		$this->assertEquals(
 			append_dir( 'asd/', '/dsa' ),
 			'asd/dsa'
 		);
 	}
 
 	/**
 	 * Test the append_dir() function with a custom glue
 	 */
 	public function testAppendDirCustomGlue() {
 		$this->assertEquals(
 			append_dir( 'asd\\', '\\dsa', '\\' ),
 			'asd\\dsa' // intended as "asd\dsa"
 		);
 	}
 
 }
diff --git a/tests/TestQuery.php b/phpunit/QueryTest.php
similarity index 85%
rename from tests/TestQuery.php
rename to phpunit/QueryTest.php
index 40accd7..0cd2b46 100644
--- a/tests/TestQuery.php
+++ b/phpunit/QueryTest.php
@@ -1,130 +1,148 @@
 <?php
 // use the phpunit framework
 use PHPUnit\Framework\TestCase;
 
 /**
  * Test Query class
  */
-final class TestQuery extends TestCase {
+final class QueryTest extends TestCase {
 
 	/**
 	 * Test the bracket and glue
 	 */
 	public function testBracketsAndGlue() {
 
 		// create a dummy query builders
 		$query  = new Query( new DBDummy() );
 
 		$query->select( 'field' );
 		$query->from( 'table'  );
 
 		$query->where( 'condition1' );
 
 		$query->openBracket()
 		      ->setGlue( 'OR' );
 
 			$query->where( 'condition2' );
 
 				$query->openBracket();
 
 				$query->where( 'condition3' );
 				$query->where( 'condition4' );
 
 				$query->closeBracket();
 
 			$query->where( 'condition5' );
 
 		$query->closeBracket()
 		      ->setGlue( 'AND' );
 
 		$query->where( 'condition6' );
 		$query->where( 'condition7' );
 
 		$this->assertEquals(
 			'SELECT field FROM `table` AS `table` WHERE condition1 AND (condition2 OR (condition3 OR condition4) OR condition5) AND condition6 AND condition7',
 			$query->getQuery()
 		);
 	}
 
 	/**
 	 * Test the EXISTS
 	 */
 	public function testExistsCondition() {
 
 		// create a couple for dummy query builders
 		$query  = new Query( new DBDummy() );
 		$query2 = new Query( new DBDummy() );
 
 		$query->from( 'one' );
 
 		$query2->from( 'two' )
 		       ->whereInt( 'two_field', 2 )
 		       ->compare(  'one.a', '<', 'two.b' );
 
 		$query->whereExists( $query2 );
 
 		$this->assertEquals(
 			'SELECT * FROM `one` AS `one` WHERE EXISTS (SELECT * FROM `two` AS `two` WHERE two_field = 2 AND one.a < two.b)',
 			$query->getQuery()
 		);
 	}
 
 	/**
 	 * Test the FROM with an alias
 	 */
 	public function testFromWithAlias() {
 		$query = new Query( new DBDummy() );
 
 		$query->fromAlias( 'one', 'asd' );
 
 		$this->assertEquals(
 			'SELECT * FROM `one` AS `asd`',
 			$query->getQuery()
 		);
 	}
 
 	/**
 	 * Allow to have a query without the FROM
 	 */
 	public function testEmptyFrom() {
 
 		$query = new Query( new DBDummy() );
 
 		$query->select( '1' );
 
 		$this->assertEquals(
 			'SELECT 1',
 			$query->getQuery()
 		);
 	}
 
 	/**
 	 * SELECT with a custom AS argument
 	 */
 	public function testSelectAs() {
 
 		$query = new Query( new DBDummy() );
 
 		$query->selectAs( '1', 'ciao' );
 
 		$this->assertEquals(
-			'SELECT (1) ciao',
+			'SELECT ( 1 ) ciao',
 			$query->getQuery()
 		);
 	}
 
 	/**
 	 * Test the SELECT with the empty AS argument
 	 */
 	public function testSelectAsEmpty() {
 
 		$query = new Query( new DBDummy() );
 
 		$query->selectAs( '1', null );
 
 		$this->assertEquals(
-			'SELECT (1)',
+			'SELECT ( 1 )',
+			$query->getQuery()
+		);
+	}
+
+	/**
+	 * Test the SELECT with a NOT EXISTS constraint
+	 */
+	public function testSelectNotExists() {
+
+		$query = new Query( new DBDummy() );
+		$sub   = new Query( new DBDummy() );
+
+		$sub->select( 1 );
+
+		$query->whereNotExists( $sub );
+
+		$this->assertEquals(
+			'SELECT * WHERE NOT EXISTS (SELECT 1)',
 			$query->getQuery()
 		);
 	}
 }
diff --git a/phpunit/README.md b/phpunit/README.md
new file mode 100644
index 0000000..eef1711
--- /dev/null
+++ b/phpunit/README.md
@@ -0,0 +1,7 @@
+# How to run a test
+
+From the parent directory:
+
+```
+phpunit --bootstrap=phpunit/load.php --testdox phpunit
+```
diff --git a/tests/load.php b/phpunit/load.php
similarity index 100%
rename from tests/load.php
rename to phpunit/load.php
diff --git a/tests/README.md b/tests/README.md
deleted file mode 100644
index 05e5a94..0000000
--- a/tests/README.md
+++ /dev/null
@@ -1,5 +0,0 @@
-# How to run a test
-
-```
-phpunit --bootstrap=load.php --testdox Test*
-```