diff --git a/config/optional/rest.resource.helfi_debug_package_version.yml b/config/optional/rest.resource.helfi_debug_package_version.yml
deleted file mode 100644
index 7762b686..00000000
--- a/config/optional/rest.resource.helfi_debug_package_version.yml
+++ /dev/null
@@ -1,16 +0,0 @@
-langcode: en
-status: true
-dependencies:
-  module:
-    - user
-id: helfi_debug_package_version
-plugin_id: 'helfi_debug_package_version'
-granularity: resource
-configuration:
-  methods:
-    - GET
-  formats:
-    - json
-  authentication:
-    - cookie
-    - basic_auth
diff --git a/documentation/debug.md b/documentation/debug.md
index 943a1a76..78503c83 100644
--- a/documentation/debug.md
+++ b/documentation/debug.md
@@ -13,14 +13,3 @@ See [src/Plugin/DebugDataItem/Composer.php](/src/Plugin/DebugDataItem/Composer.p
 At minimum, you need:
 - A plugin class that implements `\Drupal\helfi_debug\DebugDataItemInterface`
 - A plugin specific template (`debug-item--{plugin_id}.html.twig`). See [templates/debug-item.html.twig](/templates/debug-item.html.twig) for more information.
-
-## Package version checker
-
-The `/api/v1/version` endpoint can be used to fetch the latest version of a composer package.
-
-For example:
-
-Request `GET /api/v1/version?package=drupal/helfi_api_base&version=1.2.0` will respond with:
-
-- The latest version number
-- Whether the given version is the latest version
diff --git a/helfi_api_base.install b/helfi_api_base.install
index 039871db..c4105a06 100644
--- a/helfi_api_base.install
+++ b/helfi_api_base.install
@@ -338,3 +338,13 @@ function _helfi_api_base_process_links(ContentEntityInterface $entity, string $f
     $entity->save();
   }
 }
+
+/**
+ * UHF-10713 Remove VersionChecker.
+ */
+function helfi_api_base_update_9023(): void {
+  \Drupal::entityTypeManager()
+    ->getStorage('rest_resource_config')
+    ->load('helfi_debug_package_version')
+    ->delete();
+}
diff --git a/helfi_api_base.permissions.yml b/helfi_api_base.permissions.yml
index aea19c88..4076c7ff 100644
--- a/helfi_api_base.permissions.yml
+++ b/helfi_api_base.permissions.yml
@@ -11,3 +11,5 @@ view remote entities:
   title: View remote entities
 edit remote entities:
   title: Edit remote entities
+access debug page:
+  title: Access debug page
diff --git a/helfi_api_base.routing.yml b/helfi_api_base.routing.yml
index 3dc54f8f..aef22451 100644
--- a/helfi_api_base.routing.yml
+++ b/helfi_api_base.routing.yml
@@ -20,4 +20,4 @@ helfi_api_base.debug_list:
     _title: 'Debug'
     _controller: '\Drupal\helfi_api_base\Controller\DebugController::build'
   requirements:
-    _permission: 'restful get helfi_debug_package_version'
+    _permission: 'access debug page'
diff --git a/helfi_api_base.services.yml b/helfi_api_base.services.yml
index 3842e577..c62e535e 100644
--- a/helfi_api_base.services.yml
+++ b/helfi_api_base.services.yml
@@ -70,20 +70,6 @@ services:
     class: Drupal\helfi_api_base\DebugDataItemPluginManager
     parent: default_plugin_manager
 
-  Drupal\helfi_api_base\Package\VersionChecker: '@helfi_api_base.package_version_checker'
-  helfi_api_base.package_version_checker:
-    class: Drupal\helfi_api_base\Package\VersionChecker
-    arguments: []
-    tags:
-      - { name: service_collector, call: add, tag: helfi_api_base.version_checker }
-
-  Drupal\helfi_api_base\Package\HelfiPackage: '@helfi_api_base.helfi_package_version_checker'
-  helfi_api_base.helfi_package_version_checker:
-    class: Drupal\helfi_api_base\Package\HelfiPackage
-    arguments: ['@http_client']
-    tags:
-      - { name: helfi_api_base.version_checker }
-
   Drupal\helfi_api_base\EventSubscriber\EnvironmentResponseSubscriber: '@helfi_api_base.environment_response_subscriber'
   helfi_api_base.environment_response_subscriber:
     class: Drupal\helfi_api_base\EventSubscriber\EnvironmentResponseSubscriber
diff --git a/src/Exception/InvalidPackageException.php b/src/Exception/InvalidPackageException.php
deleted file mode 100644
index 8a496930..00000000
--- a/src/Exception/InvalidPackageException.php
+++ /dev/null
@@ -1,13 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Drupal\helfi_api_base\Exception;
-
-use Symfony\Component\HttpKernel\Exception\BadRequestHttpException;
-
-/**
- * Exception to indicate invalid package.
- */
-final class InvalidPackageException extends BadRequestHttpException {
-}
diff --git a/src/Package/HelfiPackage.php b/src/Package/HelfiPackage.php
deleted file mode 100644
index f1906132..00000000
--- a/src/Package/HelfiPackage.php
+++ /dev/null
@@ -1,89 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Drupal\helfi_api_base\Package;
-
-use Drupal\helfi_api_base\Exception\InvalidPackageException;
-use GuzzleHttp\ClientInterface;
-use GuzzleHttp\Exception\GuzzleException;
-
-/**
- * Provides a version checker for helfi custom modules.
- */
-final class HelfiPackage implements VersionCheckerInterface {
-
-  public const BASE_URL = 'https://repository.drupal.hel.ninja/p2/%s.json';
-
-  /**
-   * Constructs a new instance.
-   *
-   * @param \GuzzleHttp\ClientInterface $client
-   *   The HTTP client.
-   */
-  public function __construct(
-    private ClientInterface $client,
-  ) {
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function applies(string $packageName): bool {
-    // @todo Allow other city-of-helsinki packages too.
-    return str_starts_with($packageName, 'drupal/helfi_')
-      || str_starts_with($packageName, 'drupal/hdbt');
-  }
-
-  /**
-   * Gets the package data.
-   *
-   * @param string $packageName
-   *   The package name.
-   * @param bool $dev
-   *   Whether to get dev releases or not.
-   *
-   * @return array
-   *   The packages.
-   *
-   * @throws \Drupal\helfi_api_base\Exception\InvalidPackageException
-   */
-  private function getPackageData(string $packageName, bool $dev = FALSE) : array {
-    $packagePath = $dev ? sprintf('%s~dev', $packageName) : $packageName;
-
-    try {
-      $response = $this->client
-        ->request('GET', sprintf(self::BASE_URL, $packagePath));
-      $content = json_decode($response->getBody()->getContents(), TRUE);
-    }
-    catch (GuzzleException $e) {
-      return [];
-    }
-    if (!isset($content['packages'][$packageName])) {
-      throw new InvalidPackageException('Package not found.');
-    }
-    return $content['packages'][$packageName];
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function get(string $packageName, string $version): ? Version {
-    // Attempt to get package data and fallback to dev version if
-    // no stable version is found.
-    if (!$packages = $this->getPackageData($packageName)) {
-      $packages = $this->getPackageData($packageName, TRUE);
-    }
-    usort($packages, function ($package1, $package2) {
-      return version_compare($package1['version'], $package2['version']);
-    });
-    // Packages are sorted from oldest to newest.
-    $latest = end($packages);
-
-    if (empty($latest['version']) || !is_string($latest['version'])) {
-      throw new InvalidPackageException('No version data found.');
-    }
-    return new Version($packageName, $latest['version'], version_compare($version, $latest['version'], '>='));
-  }
-
-}
diff --git a/src/Package/Version.php b/src/Package/Version.php
deleted file mode 100644
index 665b7690..00000000
--- a/src/Package/Version.php
+++ /dev/null
@@ -1,43 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Drupal\helfi_api_base\Package;
-
-/**
- * A value object to store package version data.
- */
-final class Version {
-
-  /**
-   * Constructs a new instance.
-   *
-   * @param string $name
-   *   The package name.
-   * @param string $latestVersion
-   *   The version.
-   * @param bool $isLatest
-   *   Whether the given version is latest or not.
-   */
-  public function __construct(
-    public string $name,
-    public string $latestVersion,
-    public bool $isLatest,
-  ) {
-  }
-
-  /**
-   * Gets the object as an array.
-   *
-   * @return array
-   *   The data as an array.
-   */
-  public function toArray() : array {
-    return [
-      'name' => $this->name,
-      'latestVersion' => $this->latestVersion,
-      'isLatest' => $this->isLatest,
-    ];
-  }
-
-}
diff --git a/src/Package/VersionChecker.php b/src/Package/VersionChecker.php
deleted file mode 100644
index 4703becd..00000000
--- a/src/Package/VersionChecker.php
+++ /dev/null
@@ -1,56 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Drupal\helfi_api_base\Package;
-
-/**
- * Provides a package version checker.
- */
-final class VersionChecker {
-
-  /**
-   * The collectors.
-   *
-   * @var \Drupal\helfi_api_base\Package\VersionCheckerInterface[]
-   */
-  private array $collectors = [];
-
-  /**
-   * Adds a version checker.
-   *
-   * @param \Drupal\helfi_api_base\Package\VersionCheckerInterface $versionChecker
-   *   The version checker collector.
-   *
-   * @return $this
-   *   The self.
-   */
-  public function add(VersionCheckerInterface $versionChecker) : self {
-    $this->collectors[] = $versionChecker;
-    return $this;
-  }
-
-  /**
-   * Gets the package version.
-   *
-   * @param string $packageName
-   *   The package name.
-   * @param string $version
-   *   The version.
-   *
-   * @return \Drupal\helfi_api_base\Package\Version|null
-   *   The version object or null.
-   *
-   * @throws \Drupal\helfi_api_base\Exception\InvalidPackageException
-   */
-  public function get(string $packageName, string $version) : ? Version {
-    foreach ($this->collectors as $collector) {
-      if (!$collector->applies($packageName)) {
-        continue;
-      }
-      return $collector->get($packageName, $version);
-    }
-    return NULL;
-  }
-
-}
diff --git a/src/Package/VersionCheckerInterface.php b/src/Package/VersionCheckerInterface.php
deleted file mode 100644
index 64a8d119..00000000
--- a/src/Package/VersionCheckerInterface.php
+++ /dev/null
@@ -1,38 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Drupal\helfi_api_base\Package;
-
-/**
- * Defines the version checker interface.
- */
-interface VersionCheckerInterface {
-
-  /**
-   * Checks whether this collector is applicable.
-   *
-   * @param string $packageName
-   *   The package name to check.
-   *
-   * @return bool
-   *   TRUE if this instance should handle the version check.
-   */
-  public function applies(string $packageName) : bool;
-
-  /**
-   * Gets the version data.
-   *
-   * @param string $packageName
-   *   The package name.
-   * @param string $version
-   *   The version.
-   *
-   * @return \Drupal\helfi_api_base\Package\Version|null
-   *   The version or null.
-   *
-   * @throws \Drupal\helfi_api_base\Exception\InvalidPackageException
-   */
-  public function get(string $packageName, string $version) : ? Version;
-
-}
diff --git a/src/Plugin/rest/resource/PackageVersion.php b/src/Plugin/rest/resource/PackageVersion.php
index 494480ca..b6c98bc8 100644
--- a/src/Plugin/rest/resource/PackageVersion.php
+++ b/src/Plugin/rest/resource/PackageVersion.php
@@ -4,19 +4,15 @@
 
 namespace Drupal\helfi_api_base\Plugin\rest\resource;
 
-use Drupal\Component\Plugin\DependentPluginInterface;
-use Drupal\Core\Cache\CacheableMetadata;
-use Drupal\helfi_api_base\Package\Version;
-use Drupal\helfi_api_base\Package\VersionChecker;
 use Drupal\rest\Plugin\ResourceBase;
 use Drupal\rest\ResourceResponse;
-use Symfony\Component\DependencyInjection\ContainerInterface;
-use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpKernel\Exception\BadRequestHttpException;
 
 /**
  * Represents Package version as resources.
  *
+ * @todo Remove this once the REST configuration is removed from all projects.
+ *
  * @RestResource(
  *   id = "helfi_debug_package_version",
  *   label = @Translation("Package version"),
@@ -25,74 +21,15 @@
  *   }
  * )
  */
-final class PackageVersion extends ResourceBase implements DependentPluginInterface {
-
-  /**
-   * The version checker service.
-   *
-   * @var \Drupal\helfi_api_base\Package\VersionChecker
-   */
-  private VersionChecker $packageVersion;
-
-  /**
-   * {@inheritdoc}
-   */
-  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) : self {
-    $instance = parent::create(
-      $container,
-      $configuration,
-      $plugin_id,
-      $plugin_definition
-    );
-    $instance->packageVersion = $container->get('helfi_api_base.package_version_checker');
-    return $instance;
-  }
+final class PackageVersion extends ResourceBase {
 
   /**
    * Responds to GET requests.
    *
-   * @return \Drupal\rest\ResourceResponse
-   *   The response containing the record.
-   *
    * @throws \Symfony\Component\HttpKernel\Exception\HttpException
    */
-  public function get(Request $request) : ResourceResponse {
-    $args = [];
-    foreach (['name', 'version'] as $arg) {
-      if (!$value = $request->query->get($arg)) {
-        throw new BadRequestHttpException(sprintf('Missing required query argument: %s', $arg));
-      }
-      if (is_array($value)) {
-        $value = reset($value);
-      }
-      $args[$arg] = (string) $value;
-    }
-    ['name' => $name, 'version' => $version] = $args;
-
-    $data = $this->packageVersion->get($name, $version);
-
-    if (!$data instanceof Version) {
-      throw new BadRequestHttpException(sprintf('Invalid package name: %s', $name));
-    }
-
-    $cacheableMetadata = new CacheableMetadata();
-    $cacheableMetadata->addCacheContexts([
-      'url.query_args:name',
-      'url.query_args:version',
-    ])
-      ->setCacheMaxAge(180);
-
-    return (new ResourceResponse($data->toArray()))
-      ->addCacheableDependency($cacheableMetadata);
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function calculateDependencies() : array {
-    return [
-      'module' => ['user'],
-    ];
+  public function get() : ResourceResponse {
+    throw new BadRequestHttpException(sprintf('Deprecated'));
   }
 
 }
diff --git a/tests/src/Functional/DebugUiTest.php b/tests/src/Functional/DebugUiTest.php
index 86888d1d..f1588201 100644
--- a/tests/src/Functional/DebugUiTest.php
+++ b/tests/src/Functional/DebugUiTest.php
@@ -32,7 +32,7 @@ public function testDebugAdminUi() : void {
     $this->drupalGet('/admin/debug');
     $this->assertSession()->statusCodeEquals(403);
 
-    $account = $this->createUser(['restful get helfi_debug_package_version']);
+    $account = $this->createUser(['access debug page']);
     $this->drupalLogin($account);
 
     $this->drupalGet('/admin/debug');
diff --git a/tests/src/Kernel/Controller/DebugControllerTest.php b/tests/src/Kernel/Controller/DebugControllerTest.php
index 5dc4395d..c8f1c0a0 100644
--- a/tests/src/Kernel/Controller/DebugControllerTest.php
+++ b/tests/src/Kernel/Controller/DebugControllerTest.php
@@ -37,7 +37,7 @@ public function testControllerPermission() : void {
 
     $this->assertEquals(Response::HTTP_FORBIDDEN, $response->getStatusCode());
 
-    $this->drupalSetUpCurrentUser(permissions: ['restful get helfi_debug_package_version']);
+    $this->drupalSetUpCurrentUser(permissions: ['access debug page']);
     $request = $this->getMockedRequest('/admin/debug');
     $response = $this->processRequest($request);
 
diff --git a/tests/src/Kernel/Plugin/rest/resource/PackageVersionTest.php b/tests/src/Kernel/Plugin/rest/resource/PackageVersionTest.php
deleted file mode 100644
index e67d32bc..00000000
--- a/tests/src/Kernel/Plugin/rest/resource/PackageVersionTest.php
+++ /dev/null
@@ -1,155 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Drupal\Tests\helfi_api_base\Kernel\Plugin\rest\resource;
-
-use Drupal\Core\Cache\CacheableResponse;
-use Drupal\Tests\helfi_api_base\Kernel\ApiKernelTestBase;
-use Drupal\helfi_api_base\Package\HelfiPackage;
-use GuzzleHttp\Exception\RequestException;
-use GuzzleHttp\Psr7\Request;
-use GuzzleHttp\Psr7\Response;
-use Symfony\Component\HttpFoundation\Response as HttpResponse;
-
-/**
- * Tests the entity_changed plugin.
- *
- * @coversDefaultClass \Drupal\helfi_api_base\Plugin\rest\resource\PackageVersion
- * @group helfi_api_base
- */
-class PackageVersionTest extends ApiKernelTestBase {
-
-  /**
-   * {@inheritdoc}
-   */
-  protected static $modules = [
-    'migrate',
-    'serialization',
-    'rest',
-  ];
-
-  /**
-   * Creates a user with correct permissions.
-   */
-  private function setupUser() : void {
-    $user = $this->createUser(permissions: ['restful get helfi_debug_package_version']);
-    $this->drupalSetCurrentUser($user);
-  }
-
-  /**
-   * Tests request without permission.
-   */
-  public function testAccessDenied() : void {
-    $this->drupalSetUpCurrentUser();
-
-    $request = $this->getMockedRequest('/api/v1/package');
-    $response = $this->processRequest($request);
-
-    $this->assertEquals(HttpResponse::HTTP_FORBIDDEN, $response->getStatusCode());
-  }
-
-  /**
-   * Tests required query parameters.
-   *
-   * @dataProvider getDataRequiredParameters
-   */
-  public function testGetRequiredParameters(array $parameters, string $expectedErrorMessage) : void {
-    $this->setupUser();
-    $request = $this->getMockedRequest('/api/v1/package', parameters: $parameters);
-    $response = $this->processRequest($request);
-
-    $this->assertEquals(HttpResponse::HTTP_BAD_REQUEST, $response->getStatusCode());
-    $this->assertEquals($expectedErrorMessage, json_decode($response->getContent(), TRUE)['message']);
-  }
-
-  /**
-   * A data provider.
-   *
-   * @return array[]
-   *   The data.
-   */
-  public function getDataRequiredParameters() : array {
-    return [
-      [
-        [], 'Missing required query argument: name',
-      ],
-      [
-        ['name' => 'drupal/helfi_api_base'], 'Missing required query argument: version',
-      ],
-    ];
-  }
-
-  /**
-   * Tests invalid package name.
-   */
-  public function testInvalidPackageName() : void {
-    $this->setupUser();
-    $request = $this->getMockedRequest('/api/v1/package', parameters: [
-      'name' => 'drupal/invalid',
-      'version' => '1.0.0',
-    ]);
-    $response = $this->processRequest($request);
-
-    $this->assertEquals(HttpResponse::HTTP_BAD_REQUEST, $response->getStatusCode());
-    $this->assertEquals('Invalid package name: drupal/invalid', json_decode($response->getContent(), TRUE)['message']);
-  }
-
-  /**
-   * Tests requests that lead to InvalidPackageException error.
-   */
-  public function testInvalidPackageException() : void {
-    \Drupal::service('kernel')->rebuildContainer();
-
-    $client = $this->createMockHttpClient([
-      new RequestException('message', new Request('GET', 'test')),
-      new RequestException('message', new Request('GET', 'test')),
-    ]);
-    $this->container->set('helfi_api_base.helfi_package_version_checker', new HelfiPackage($client));
-
-    $request = $this->getMockedRequest('/api/v1/package', parameters: [
-      'name' => 'drupal/helfi_api_base',
-      'version' => '1.0.0',
-    ]);
-
-    $this->setupUser();
-    $response = $this->processRequest($request);
-
-    $this->assertEquals(HttpResponse::HTTP_BAD_REQUEST, $response->getStatusCode());
-    $this->assertEquals('No version data found.', json_decode($response->getContent(), TRUE)['message']);
-  }
-
-  /**
-   * Tests get request and cache contexts.
-   */
-  public function testGet() : void {
-    \Drupal::service('kernel')->rebuildContainer();
-    $client = $this->createMockHttpClient([
-      new Response(body: json_encode([
-        'packages' => [
-          'drupal/helfi_api_base' => [
-            [
-              'version' => '1.2.0',
-            ],
-          ],
-        ],
-      ])),
-    ]);
-    $this->container->set('helfi_api_base.helfi_package_version_checker', new HelfiPackage($client));
-
-    $request = $this->getMockedRequest('/api/v1/package', parameters: [
-      'name' => 'drupal/helfi_api_base',
-      'version' => '1.0.0',
-    ]);
-    $this->setupUser();
-    $response = $this->processRequest($request);
-
-    $this->assertInstanceOf(CacheableResponse::class, $response);
-    // Make sure our response is not sent to actual API.
-    $this->assertEquals('1.2.0', json_decode($response->getContent(), TRUE)['latestVersion']);
-    $this->assertContains('url.query_args:name', $response->getCacheableMetadata()->getCacheContexts());
-    $this->assertContains('url.query_args:version', $response->getCacheableMetadata()->getCacheContexts());
-    $this->assertEquals(180, $response->getCacheableMetadata()->getCacheMaxAge());
-  }
-
-}
diff --git a/tests/src/Unit/Package/HelfiPackageTest.php b/tests/src/Unit/Package/HelfiPackageTest.php
deleted file mode 100644
index e6f712ad..00000000
--- a/tests/src/Unit/Package/HelfiPackageTest.php
+++ /dev/null
@@ -1,238 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Drupal\Tests\helfi_api_base\Unit\Package;
-
-use Drupal\Tests\UnitTestCase;
-use Drupal\Tests\helfi_api_base\Traits\ApiTestTrait;
-use Drupal\helfi_api_base\Exception\InvalidPackageException;
-use Drupal\helfi_api_base\Package\HelfiPackage;
-use Drupal\helfi_api_base\Package\Version;
-use GuzzleHttp\ClientInterface;
-use GuzzleHttp\Exception\RequestException;
-use GuzzleHttp\Psr7\Request;
-use GuzzleHttp\Psr7\Response;
-use Prophecy\PhpUnit\ProphecyTrait;
-
-/**
- * Tests Helfi package collector.
- *
- * @coversDefaultClass \Drupal\helfi_api_base\Package\HelfiPackage
- * @group helfi_api_base
- */
-class HelfiPackageTest extends UnitTestCase {
-
-  use ApiTestTrait;
-  use ProphecyTrait;
-
-  /**
-   * Tests applies().
-   *
-   * @covers ::applies
-   * @covers ::__construct
-   * @dataProvider appliesData
-   */
-  public function testApplies(string $package, bool $expected) : void {
-    $sut = new HelfiPackage($this->prophesize(ClientInterface::class)->reveal());
-    $this->assertEquals($expected, $sut->applies($package));
-  }
-
-  /**
-   * Data provider for applies() test.
-   *
-   * @return array[]
-   *   The data.
-   */
-  public function appliesData() : array {
-    return [
-      ['drupal/helfi_api_base', TRUE],
-      ['drupal/hdbt', TRUE],
-      ['drupal/hdbt_admin', TRUE],
-      ['city-of-helsinki/hauki', FALSE],
-    ];
-  }
-
-  /**
-   * Tests empty version.
-   *
-   * @covers ::get
-   * @covers ::__construct
-   * @covers ::getPackageData
-   * @dataProvider emptyVersionData
-   */
-  public function testEmptyVersion($version) : void {
-    $client = $this->createMockHttpClient([
-      new Response(body: json_encode([
-        'packages' => [
-          'drupal/helfi_api_base' => [
-            [
-              'version' => $version,
-            ],
-          ],
-        ],
-      ])),
-    ]);
-    $sut = new HelfiPackage($client);
-    $this->expectException(InvalidPackageException::class);
-    $this->expectExceptionMessage('No version data found.');
-    $sut->get('drupal/helfi_api_base', '1.2.0');
-  }
-
-  /**
-   * Data provider for empty version check.
-   *
-   * @return array
-   *   The data.
-   */
-  public function emptyVersionData() : array {
-    return [
-      [NULL],
-      [1],
-      [''],
-    ];
-  }
-
-  /**
-   * Tests that client error returns null.
-   *
-   * @covers ::get
-   * @covers ::__construct
-   * @covers ::getPackageData
-   */
-  public function testException() : void {
-    // First we try to fetch stable version, then fallback to dev.
-    $client = $this->createMockHttpClient([
-      new RequestException('Stable package', new Request('GET', 'test')),
-      new RequestException('Dev package', new Request('GET', 'test')),
-    ]);
-    $sut = new HelfiPackage($client);
-    $this->expectException(InvalidPackageException::class);
-    $this->expectExceptionMessage('No version data found.');
-    $sut->get('drupal/helfi_api_base', '1.2.0');
-  }
-
-  /**
-   * Tests empty packages.
-   *
-   * @covers ::get
-   * @covers ::__construct
-   * @covers ::getPackageData
-   */
-  public function testEmptyPackage() : void {
-    $client = $this->createMockHttpClient([
-      new Response(body: json_encode([
-        'packages' => [],
-      ])),
-    ]);
-    $sut = new HelfiPackage($client);
-    $this->expectException(InvalidPackageException::class);
-    $this->expectExceptionMessage('Package not found.');
-    $sut->get('drupal/helfi_api_base', '1.2.0');
-  }
-
-  /**
-   * Tests get().
-   *
-   * @covers ::__construct
-   * @covers ::get
-   * @covers \Drupal\helfi_api_base\Package\Version
-   * @covers ::getPackageData
-   *
-   * @dataProvider getData
-   */
-  public function testGet(
-    string $packageName,
-    array $packageVersions,
-    string $packageVersion,
-    string $expectedLatestVersion,
-    bool $isLatest,
-  ) : void {
-    $client = $this->createMockHttpClient([
-      new Response(body: json_encode([
-        'packages' => [
-          $packageName => $packageVersions,
-        ],
-      ])),
-    ]);
-    $sut = new HelfiPackage($client);
-    $result = $sut->get($packageName, $packageVersion);
-    $this->assertInstanceOf(Version::class, $result);
-    $this->assertEquals($packageName, $result->name);
-    $this->assertEquals($expectedLatestVersion, $result->latestVersion);
-    $this->assertEquals($isLatest, $result->isLatest);
-    $this->assertNotEmpty($result->toArray());
-  }
-
-  /**
-   * Data provider for get().
-   *
-   * @return array[]
-   *   The data.
-   */
-  public function getData() : array {
-    return [
-      // Test with same version.
-      [
-        'drupal/helfi_api_base',
-        [
-          [
-            'version' => '1.2.0',
-          ],
-          [
-            'version' => '1.3.0',
-          ],
-        ],
-        '1.3.0',
-        '1.3.0',
-        TRUE,
-      ],
-      // Test with dev-main.
-      [
-        'drupal/helfi_api_base',
-        [
-          [
-            'version' => '1.2.0',
-          ],
-          [
-            'version' => '1.3.0',
-          ],
-        ],
-        'dev-main',
-        '1.3.0',
-        FALSE,
-      ],
-      // Test with future release.
-      [
-        'drupal/helfi_api_base',
-        [
-          [
-            'version' => '1.2.0',
-          ],
-          [
-            'version' => '1.3.0',
-          ],
-        ],
-        '1.4.0',
-        '1.3.0',
-        TRUE,
-      ],
-      // Test older release.
-      [
-        'drupal/hdbt',
-        [
-          [
-            'version' => '1.2.0',
-          ],
-          [
-            'version' => '1.3.0',
-          ],
-        ],
-        '1.2.0',
-        '1.3.0',
-        FALSE,
-      ],
-    ];
-  }
-
-}