diff --git a/README.md b/README.md
new file mode 100644
index 0000000..fc5872e
--- /dev/null
+++ b/README.md
@@ -0,0 +1,41 @@
+# PHPUnit Test Splitter
+
+Allows you to split your PHPUnit tests by timings.
+
+## Usage
+
+Generate a timing file:
+
+```bash
+phpunit --cache-result --cache-result-file=.phpunit.result.cache
+```
+
+List your tests:
+
+```bash
+phpunit --list-tests-xml=tests.xml 
+```
+
+This generates an XML file with a list of tests. You can add `--testsuite` to limit the tests to a specific suite.
+
+Split the tests in 2 groups and get the first group (0):
+
+```bash
+phpunit-splitter 2 0 --tests-file=tests.xml --results-file=.phpunit.result.cache
+```
+
+Split the tests in 4 groups and get the third group (2):
+
+```bash
+phpunit-splitter 4 2 --tests-file=tests.xml --results-file=.phpunit.result.cache
+```
+
+Pass the results to PHPUnit:
+
+```bash
+./phpunit-splitter 2 0 --tests-file=tests/fixtures/tests.xml --results-file=tests/fixtures/.phpunit.result.cache | while IFS= read -r line; do
+    filepath=$(echo "$line" | awk '{print $NF}')
+    testname=$(echo "$line" | awk '{$NF=""; print $0}')
+    ./vendor/bin/phpunit --filter="$testname" $filepath
+done
+```
diff --git a/composer.json b/composer.json
index f40c142..432db01 100644
--- a/composer.json
+++ b/composer.json
@@ -11,14 +11,18 @@
   "type": "project",
   "require": {
     "php": "^8.1",
+    "ext-simplexml": "*",
     "phpunit/phpunit": "^9.6",
-    "previousnext/phpunit-finder": "^2.0"
+    "previousnext/phpunit-finder": "^2.0",
+    "symfony/console": "^6.3"
   },
   "autoload": {
     "psr-4": {"PhpUnitSplitter\\": "src/"}
   },
   "autoload-dev": {
-    "psr-4": {"PhpUnitSplitter\\Tests\\": "tests/"}
+    "psr-4": {
+      "PhpUnitSplitter\\Tests\\": "tests/"
+    }
   },
   "config": {
     "sort-packages": true
diff --git a/phpunit-splitter b/phpunit-splitter
new file mode 100755
index 0000000..2d28aaa
--- /dev/null
+++ b/phpunit-splitter
@@ -0,0 +1,33 @@
+#!/usr/bin/env php
+<?php
+/**
+ * @file
+ * Console application for PHPUnit Splitter.
+ */
+
+$autoload = [
+  __DIR__ . '/vendor/autoload.php',
+  dirname(__DIR__, 1) . '/vendor/autoload.php',
+  dirname(__DIR__, 2) . '/vendor/autoload.php',
+  dirname(__DIR__, 1) . '/autoload.php',
+  dirname(__DIR__, 2) . '/autoload.php',
+];
+foreach ($autoload as $file) {
+  if (file_exists($file)) {
+    require $file;
+    break;
+  }
+}
+
+const APP_NAME = 'PHPUnit Splitter';
+const VERSION = '1.x-dev';
+
+use PhpUnitSplitter\SplitterCommand;
+use Symfony\Component\Console\Application;
+
+
+$application = new Application(APP_NAME, VERSION);
+$command = new SplitterCommand('phpunit-splitter');
+$application->add($command);
+$application->setDefaultCommand($command->getName(), TRUE);
+$application->run();
diff --git a/scripts/generate-fixtures.sh b/scripts/generate-fixtures.sh
new file mode 100755
index 0000000..02d4b63
--- /dev/null
+++ b/scripts/generate-fixtures.sh
@@ -0,0 +1,3 @@
+#!/bin/bash
+./vendor/bin/phpunit --list-tests-xml=tests/fixtures/tests.xml tests/fixtures/Test
+./vendor/bin/phpunit tests/fixtures/Test --cache-result --cache-result-file=tests/fixtures/.phpunit.result.cache
diff --git a/src/SplitterCommand.php b/src/SplitterCommand.php
new file mode 100644
index 0000000..f0b194e
--- /dev/null
+++ b/src/SplitterCommand.php
@@ -0,0 +1,67 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpUnitSplitter;
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\OutputInterface;
+
+/**
+ * A symfony command for splitting PHPUnit tests.
+ */
+class SplitterCommand extends Command {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function configure(): void {
+    $this->addArgument('splits', InputArgument::OPTIONAL, "The number of splits", 1);
+    $this->addArgument('index', InputArgument::OPTIONAL, "The index of the current split", 0);
+    $this->addOption('tests-file', 't', InputOption::VALUE_REQUIRED, "The xml file listing all tests.", getcwd() . './tests.xml');
+    $this->addOption('results-file', 'f', InputOption::VALUE_REQUIRED, "The results cache file.", getcwd() . '/.phpunit.result.cache', );
+    $this->addOption('bootstrap-file', 'b', InputOption::VALUE_OPTIONAL, "The tests bootstrap file.", getcwd() . '/tests/bootstrap.php');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function execute(InputInterface $input, OutputInterface $output): int {
+    $bootstrap = $input->getOption('bootstrap-file');
+    if (\file_exists($bootstrap)) {
+      include_once $bootstrap;
+    }
+    // @todo validation
+    $splits = (int) $input->getArgument('splits');
+    $index = (int) $input->getArgument('index');
+    $testsFile = $input->getOption('tests-file');
+    $resultsFile = $input->getOption('results-file');
+
+    $mapper = new TestMapper($testsFile, $resultsFile);
+    $map = $mapper->sortMap($mapper->getMap());
+
+    foreach ($this->split($map, $splits, $index) as $testName => $test) {
+      $output->writeln(\addslashes($testName) . ' ' . $test['path']);
+    }
+
+    return 0;
+  }
+
+  private function split(array $map, int $splits, int $index): array {
+    $result = [];
+    $keys = array_keys($map);
+    $values = array_values($map);
+
+    for ($i = $index; $i < count($map); $i++) {
+      if (($i - $index) % $splits === 0) {
+        $result[$keys[$i]] = $values[$i];
+      }
+    }
+
+    return $result;
+  }
+
+}
diff --git a/src/TestMapper.php b/src/TestMapper.php
new file mode 100644
index 0000000..17f4c43
--- /dev/null
+++ b/src/TestMapper.php
@@ -0,0 +1,60 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpUnitSplitter;
+
+use PHPUnit\Runner\DefaultTestResultCache;
+use PHPUnit\Runner\TestResultCache;
+
+/**
+ * Generates a map of test methods with their file name and execution time.
+ */
+final class TestMapper {
+
+  private \SimpleXMLElement|FALSE $testsXml;
+  private TestResultCache $resultCache;
+
+  public function __construct(string $testListFilePath, string $testResultFilePath) {
+    $this->testsXml = \simplexml_load_file($testListFilePath);
+    $this->resultCache = new DefaultTestResultCache($testResultFilePath);
+  }
+
+  public function getMap(): array {
+    $this->resultCache->load();
+    $map = [];
+    $classesXpath = $this->testsXml->xpath('//testCaseClass');
+    foreach ($classesXpath as $class) {
+      $className = (string) $class->attributes()['name'];
+      try {
+        $reflection = new \ReflectionClass($className);
+      }
+      catch (\ReflectionException $e) {
+        // Couldn't find the class.
+        continue;
+      }
+      $filename = $reflection->getFileName();
+      $testCases = $class->xpath('testCaseMethod');
+      foreach ($testCases as $testCase) {
+        $testName = $reflection->getShortName() . '::' . $testCase->attributes()['name'];
+        $dataSet = $testCase->attributes()['dataSet'] ?? NULL;
+        if ($dataSet !== NULL) {
+          $testName .= " with data set $dataSet";
+        }
+        $map[$testName] = [
+          'path' => $filename,
+          'time' => $this->resultCache->getTime($testName),
+        ];
+      }
+    }
+    return $map;
+  }
+
+  public function sortMap(array $map): array {
+    uasort($map, function ($a, $b) {
+      return $a['time'] <=> $b['time'];
+    });
+    return $map;
+  }
+
+}
diff --git a/tests/PhpUnitSplitterTest.php b/tests/PhpUnitSplitterTest.php
new file mode 100644
index 0000000..38de73f
--- /dev/null
+++ b/tests/PhpUnitSplitterTest.php
@@ -0,0 +1,55 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpUnitSplitter\Tests;
+
+use PHPUnit\Framework\TestCase;
+use PhpUnitSplitter\TestMapper;
+
+class PhpUnitSplitterTest extends TestCase {
+
+  public function testSplitter(): void {
+    $fixtures = dirname(__DIR__) . '/tests/fixtures';
+    $mapper = new TestMapper("$fixtures/tests.xml", "$fixtures/.phpunit.result.cache");
+    $map = $mapper->getMap();
+
+    $this->assertSame([
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\FastTestsTest::testOne',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\FastTestsTest::testTwo',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\FastTestsTest::testThree',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\FastTestsTest::testFour',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\FastTestsTest::testFive',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set "one"',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set "two"',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set "three"',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set "four"',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set "five"',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\SlowTestsTest::testOne',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\SlowTestsTest::testTwo',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\SlowTestsTest::testThree',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\SlowTestsTest::testFour',
+      'PhpUnitSplitter\\Tests\\fixtures\\Test\\SlowTestsTest::testFive',
+    ], array_keys($map));
+
+    $sorted = $mapper->sortMap($map);
+    $this->assertSame([
+      'PhpUnitSplitter\Tests\fixtures\Test\FastTestsTest::testOne',
+      'PhpUnitSplitter\Tests\fixtures\Test\FastTestsTest::testTwo',
+      'PhpUnitSplitter\Tests\fixtures\Test\FastTestsTest::testThree',
+      'PhpUnitSplitter\Tests\fixtures\Test\FastTestsTest::testFour',
+      'PhpUnitSplitter\Tests\fixtures\Test\FastTestsTest::testFive',
+      'PhpUnitSplitter\Tests\fixtures\Test\SlowTestsTest::testOne',
+      'PhpUnitSplitter\Tests\fixtures\Test\ProviderTest::testProvider with data set "one"',
+      'PhpUnitSplitter\Tests\fixtures\Test\SlowTestsTest::testTwo',
+      'PhpUnitSplitter\Tests\fixtures\Test\ProviderTest::testProvider with data set "three"',
+      'PhpUnitSplitter\Tests\fixtures\Test\SlowTestsTest::testThree',
+      'PhpUnitSplitter\Tests\fixtures\Test\ProviderTest::testProvider with data set "four"',
+      'PhpUnitSplitter\Tests\fixtures\Test\SlowTestsTest::testFour',
+      'PhpUnitSplitter\Tests\fixtures\Test\ProviderTest::testProvider with data set "two"',
+      'PhpUnitSplitter\Tests\fixtures\Test\SlowTestsTest::testFive',
+      'PhpUnitSplitter\Tests\fixtures\Test\ProviderTest::testProvider with data set "five"',
+    ], array_keys($sorted));
+
+  }
+}
diff --git a/tests/fixtures/.phpunit.result.cache b/tests/fixtures/.phpunit.result.cache
new file mode 100644
index 0000000..b104715
--- /dev/null
+++ b/tests/fixtures/.phpunit.result.cache
@@ -0,0 +1 @@
+{"version":1,"defects":[],"times":{"PhpUnitSplitter\\Tests\\fixtures\\Test\\FastTestsTest::testOne":0.012,"PhpUnitSplitter\\Tests\\fixtures\\Test\\FastTestsTest::testTwo":0.02,"PhpUnitSplitter\\Tests\\fixtures\\Test\\FastTestsTest::testThree":0.03,"PhpUnitSplitter\\Tests\\fixtures\\Test\\FastTestsTest::testFour":0.04,"PhpUnitSplitter\\Tests\\fixtures\\Test\\FastTestsTest::testFive":0.05,"PhpUnitSplitter\\Tests\\fixtures\\Test\\SlowTestsTest::testOne":0.1,"PhpUnitSplitter\\Tests\\fixtures\\Test\\SlowTestsTest::testTwo":0.2,"PhpUnitSplitter\\Tests\\fixtures\\Test\\SlowTestsTest::testThree":0.3,"PhpUnitSplitter\\Tests\\fixtures\\Test\\SlowTestsTest::testFour":0.4,"PhpUnitSplitter\\Tests\\fixtures\\Test\\SlowTestsTest::testFive":0.5,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set #0":1,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set #1":0.111,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set #2":0.445,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set #3":0.222,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set #4":0.334,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set #5":0.667,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set \"one\"":0.111,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set \"two\"":0.445,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set \"three\"":0.222,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set \"four\"":0.334,"PhpUnitSplitter\\Tests\\fixtures\\Test\\ProviderTest::testProvider with data set \"five\"":0.667}}
\ No newline at end of file
diff --git a/tests/fixtures/Test/FastTestsTest.php b/tests/fixtures/Test/FastTestsTest.php
new file mode 100644
index 0000000..a828257
--- /dev/null
+++ b/tests/fixtures/Test/FastTestsTest.php
@@ -0,0 +1,36 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpUnitSplitter\Tests\fixtures\Test;
+
+use PHPUnit\Framework\TestCase;
+
+class FastTestsTest extends TestCase {
+
+  function testOne(): void {
+    usleep(10000);
+    $this->assertTrue(TRUE);
+  }
+
+  function testTwo(): void {
+    usleep(20000);
+    $this->assertTrue(TRUE);
+  }
+
+  function testThree(): void {
+    usleep(30000);
+    $this->assertTrue(TRUE);
+  }
+
+  function testFour(): void {
+    usleep(40000);
+    $this->assertTrue(TRUE);
+  }
+
+  function testFive(): void {
+    usleep(50000);
+    $this->assertTrue(TRUE);
+  }
+
+}
diff --git a/tests/fixtures/Test/ProviderTest.php b/tests/fixtures/Test/ProviderTest.php
new file mode 100644
index 0000000..84f452a
--- /dev/null
+++ b/tests/fixtures/Test/ProviderTest.php
@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpUnitSplitter\Tests\fixtures\Test;
+
+use PHPUnit\Framework\TestCase;
+
+class ProviderTest extends TestCase {
+
+  /**
+   * @dataProvider provider
+   */
+  function testProvider(int $sleep): void {
+    usleep($sleep);
+    $this->assertTrue(TRUE);
+  }
+
+  public function provider(): array {
+    return [
+      'one' => [111111],
+      'two' => [444444],
+      'three' => [222222],
+      'four' => [333333],
+      'five' => [666666],
+    ];
+  }
+
+
+}
diff --git a/tests/fixtures/Test/SlowTestsTest.php b/tests/fixtures/Test/SlowTestsTest.php
new file mode 100644
index 0000000..aff68ab
--- /dev/null
+++ b/tests/fixtures/Test/SlowTestsTest.php
@@ -0,0 +1,36 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpUnitSplitter\Tests\fixtures\Test;
+
+use PHPUnit\Framework\TestCase;
+
+class SlowTestsTest extends TestCase {
+
+  function testOne(): void {
+    usleep(100000);
+    $this->assertTrue(TRUE);
+  }
+
+  function testTwo(): void {
+    usleep(200000);
+    $this->assertTrue(TRUE);
+  }
+
+  function testThree(): void {
+    usleep(300000);
+    $this->assertTrue(TRUE);
+  }
+
+  function testFour(): void {
+    usleep(400000);
+    $this->assertTrue(TRUE);
+  }
+
+  function testFive(): void {
+    usleep(500000);
+    $this->assertTrue(TRUE);
+  }
+
+}
diff --git a/tests/fixtures/tests.xml b/tests/fixtures/tests.xml
new file mode 100644
index 0000000..e768471
--- /dev/null
+++ b/tests/fixtures/tests.xml
@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<tests>
+ <testCaseClass name="PhpUnitSplitter\Tests\fixtures\Test\FastTestsTest">
+  <testCaseMethod name="testOne" groups="default"/>
+  <testCaseMethod name="testTwo" groups="default"/>
+  <testCaseMethod name="testThree" groups="default"/>
+  <testCaseMethod name="testFour" groups="default"/>
+  <testCaseMethod name="testFive" groups="default"/>
+ </testCaseClass>
+ <testCaseClass name="PhpUnitSplitter\Tests\fixtures\Test\ProviderTest">
+  <testCaseMethod name="testProvider" groups="default" dataSet="&quot;one&quot;"/>
+  <testCaseMethod name="testProvider" groups="default" dataSet="&quot;two&quot;"/>
+  <testCaseMethod name="testProvider" groups="default" dataSet="&quot;three&quot;"/>
+  <testCaseMethod name="testProvider" groups="default" dataSet="&quot;four&quot;"/>
+  <testCaseMethod name="testProvider" groups="default" dataSet="&quot;five&quot;"/>
+ </testCaseClass>
+ <testCaseClass name="PhpUnitSplitter\Tests\fixtures\Test\SlowTestsTest">
+  <testCaseMethod name="testOne" groups="default"/>
+  <testCaseMethod name="testTwo" groups="default"/>
+  <testCaseMethod name="testThree" groups="default"/>
+  <testCaseMethod name="testFour" groups="default"/>
+  <testCaseMethod name="testFive" groups="default"/>
+ </testCaseClass>
+</tests>