diff --git a/bin/readme/installing-body.md b/bin/readme/installing-body.md
deleted file mode 100644
index 6da5f40..0000000
--- a/bin/readme/installing-body.md
+++ /dev/null
@@ -1,13 +0,0 @@
-`wp doctor` is available to [runcommand gold and silver subscribers](https://runcommand.io/pricing/).
-
-Once you've signed up, you can [download the latest version](https://runcommand.memberful.com/account/downloads) from your account dashboard. Then, install `wp doctor` with:
-
-```
-$ wp package install doctor.zip
-```
-
-If you have a Github developer seat, you can also run:
-
-```
-$ wp package install git@github.com:runcommand/doctor.git
-```
diff --git a/command.php b/command.php
deleted file mode 100644
index 87070d6..0000000
--- a/command.php
+++ /dev/null
@@ -1,27 +0,0 @@
-<?php
-
-if ( ! class_exists( 'WP_CLI' ) ) {
-	return;
-}
-
-spl_autoload_register(
-	function ( $class_name ) {
-			$class_name = ltrim( $class_name, '\\' );
-		if ( 0 !== stripos( $class_name, 'runcommand\\Doctor\\' ) ) {
-			return;
-		}
-
-			$parts = explode( '\\', $class_name );
-			array_shift( $parts ); // Don't need "runcommand\Doctor"
-			array_shift( $parts );
-			$last    = array_pop( $parts ); // File should be 'class-[...].php'
-			$last    = 'class-' . $last . '.php';
-			$parts[] = $last;
-			$file    = __DIR__ . '/inc/' . str_replace( '_', '-', strtolower( implode( '/', $parts ) ) );
-		if ( file_exists( $file ) ) {
-			require $file;
-		}
-	}
-);
-
-WP_CLI::add_command( 'doctor', 'runcommand\Doctor\Command' );
diff --git a/composer.json b/composer.json
index beed2f6..f578136 100644
--- a/composer.json
+++ b/composer.json
@@ -37,7 +37,7 @@
     },
     "extra": {
         "branch-alias": {
-            "dev-master": "2.x-dev"
+            "dev-main": "2.x-dev"
         },
         "commands": [
             "doctor",
@@ -57,8 +57,11 @@
         }
     },
     "autoload": {
+        "psr-4": {
+            "WP_CLI\\Doctor\\": "src/"
+        },
         "files": [
-            "command.php"
+            "doctor-command.php"
         ]
     },
     "minimum-stability": "dev",
diff --git a/doctor-command.php b/doctor-command.php
new file mode 100644
index 0000000..067b476
--- /dev/null
+++ b/doctor-command.php
@@ -0,0 +1,13 @@
+<?php
+
+if ( ! class_exists( 'WP_CLI' ) ) {
+	return;
+}
+
+$wpcli_doctor_autoloader = __DIR__ . '/vendor/autoload.php';
+
+if ( file_exists( $wpcli_doctor_autoloader ) ) {
+	require_once $wpcli_doctor_autoloader;
+}
+
+WP_CLI::add_command( 'doctor', 'WP_CLI\Doctor\Command' );
diff --git a/features/check-autoload-options-size.feature b/features/check-autoload-options-size.feature
index 5f5fa33..1630fb6 100644
--- a/features/check-autoload-options-size.feature
+++ b/features/check-autoload-options-size.feature
@@ -51,7 +51,7 @@ Feature: Check the size of autoloaded options
     And a custom.yml file:
       """
       autoload-options-size:
-        class: runcommand\Doctor\Checks\Autoload_Options_Size
+        class: WP_CLI\Doctor\Check\Autoload_Options_Size
         options:
           threshold_kb: 800
       """
diff --git a/features/check-constant-definition.feature b/features/check-constant-definition.feature
index 217e4d1..0695ea5 100644
--- a/features/check-constant-definition.feature
+++ b/features/check-constant-definition.feature
@@ -71,7 +71,7 @@ Feature: Check the values of defined constants
     And a config.yml file:
       """
       constant-db-host-defined:
-        class: runcommand\Doctor\Checks\Constant_Definition
+        class: WP_CLI\Doctor\Check\Constant_Definition
         options:
           constant: DB_HOST
           defined: true
@@ -87,7 +87,7 @@ Feature: Check the values of defined constants
     And a config.yml file:
       """
       constant-foobar-true:
-        class: runcommand\Doctor\Checks\Constant_Definition
+        class: WP_CLI\Doctor\Check\Constant_Definition
         options:
           constant: FOOBAR
           value: true
@@ -108,7 +108,7 @@ Feature: Check the values of defined constants
     And a config.yml file:
       """
       constant-foobar-true:
-        class: runcommand\Doctor\Checks\Constant_Definition
+        class: WP_CLI\Doctor\Check\Constant_Definition
         options:
           constant: FOOBAR
           value: true
diff --git a/features/check-plugin-active-count.feature b/features/check-plugin-active-count.feature
index b2a43dd..99cca3d 100644
--- a/features/check-plugin-active-count.feature
+++ b/features/check-plugin-active-count.feature
@@ -22,7 +22,7 @@ Feature: Check whether a high number of plugins are activated
     And a config.yml file:
       """
       plugin-active-count:
-        class: runcommand\Doctor\Checks\Plugin_Active_Count
+        class: WP_CLI\Doctor\Check\Plugin_Active_Count
         options:
           threshold_count: 3
       """
diff --git a/features/check-plugin-deactivated.feature b/features/check-plugin-deactivated.feature
index fb2766e..ed9264f 100644
--- a/features/check-plugin-deactivated.feature
+++ b/features/check-plugin-deactivated.feature
@@ -32,7 +32,7 @@ Feature: Check whether a high percentage of plugins are deactivated
     And a custom.yml file:
       """
       plugin-deactivated:
-        class: runcommand\Doctor\Checks\Plugin_Deactivated
+        class: WP_CLI\Doctor\Check\Plugin_Deactivated
         options:
           threshold_percentage: 60
       """
diff --git a/features/check-plugin-status.feature b/features/check-plugin-status.feature
index 0fa05a2..8e705ec 100644
--- a/features/check-plugin-status.feature
+++ b/features/check-plugin-status.feature
@@ -5,7 +5,7 @@ Feature: Check the status of a plugin
     And a config.yml file:
       """
       plugin-akismet-active:
-        class: runcommand\Doctor\Checks\Plugin_Status
+        class: WP_CLI\Doctor\Check\Plugin_Status
         options:
           name: akismet
           status: active
@@ -21,12 +21,12 @@ Feature: Check the status of a plugin
     And a config.yml file:
       """
       plugin-akismet-active:
-        class: runcommand\Doctor\Checks\Plugin_Status
+        class: WP_CLI\Doctor\Check\Plugin_Status
         options:
           name: akismet
           status: active
       plugin-hello-uninstalled:
-        class: runcommand\Doctor\Checks\Plugin_Status
+        class: WP_CLI\Doctor\Check\Plugin_Status
         options:
           name: hello
           status: uninstalled
@@ -71,7 +71,7 @@ Feature: Check the status of a plugin
     And a config.yml file:
       """
       plugin-akismet-active-network:
-        class: runcommand\Doctor\Checks\Plugin_Status
+        class: WP_CLI\Doctor\Check\Plugin_Status
         options:
           name: akismet
           status: active-network
diff --git a/features/config.feature b/features/config.feature
index d23ed81..94053b4 100644
--- a/features/config.feature
+++ b/features/config.feature
@@ -42,7 +42,7 @@ Feature: Configure the Doctor
     And a config.yml file:
       """
       check space:
-        class: runcommand\Doctor\Checks\Constant_Definition
+        class: WP_CLI\Doctor\Check\Constant_Definition
       """
 
     When I try `wp doctor check --all --config=config.yml`
@@ -175,7 +175,7 @@ Feature: Configure the Doctor
       /**
        * Ensures Akismet is activated with the appropriate credentials.
        */
-      class Akismet_Valid_API_Key extends runcommand\Doctor\Checks\Check {
+      class Akismet_Valid_API_Key extends WP_CLI\Doctor\Check {
 
         public function run() {
           // If the Akismet isn't activated, bail early.
diff --git a/phpcs.xml.dist b/phpcs.xml.dist
index 8e8c9d4..a3b80cb 100644
--- a/phpcs.xml.dist
+++ b/phpcs.xml.dist
@@ -1,5 +1,5 @@
 <?xml version="1.0"?>
-<ruleset name="WP-CLI-entity">
+<ruleset name="WP-CLI-doctor">
 	<description>Custom ruleset for WP-CLI doctor-command</description>
 
 	<!--
diff --git a/inc/checks/class-check.php b/src/Check.php
similarity index 97%
rename from inc/checks/class-check.php
rename to src/Check.php
index 9b9b1a6..c0fc4e2 100644
--- a/inc/checks/class-check.php
+++ b/src/Check.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor;
 
 use WP_CLI;
 
diff --git a/inc/checks/class-autoload-options-size.php b/src/Check/Autoload_Options_Size.php
similarity index 95%
rename from inc/checks/class-autoload-options-size.php
rename to src/Check/Autoload_Options_Size.php
index a614826..db2437d 100644
--- a/inc/checks/class-autoload-options-size.php
+++ b/src/Check/Autoload_Options_Size.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Warns when autoloaded options size exceeds threshold of %threshold_kb% kb.
diff --git a/inc/checks/class-cache-flush.php b/src/Check/Cache_Flush.php
similarity index 90%
rename from inc/checks/class-cache-flush.php
rename to src/Check/Cache_Flush.php
index 396609c..3fb40e2 100644
--- a/inc/checks/class-cache-flush.php
+++ b/src/Check/Cache_Flush.php
@@ -1,8 +1,10 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
+use FilesystemIterator;
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 use RecursiveDirectoryIterator;
 use RecursiveIteratorIterator;
 
@@ -15,7 +17,7 @@ public function run() {
 
 		// Path to wp-content directory.
 		$wp_content_dir = defined( 'WP_CONTENT_DIR' ) ? WP_CONTENT_DIR : ABSPATH . 'wp-content';
-		$directory      = new RecursiveDirectoryIterator( $wp_content_dir, RecursiveDirectoryIterator::SKIP_DOTS );
+		$directory      = new RecursiveDirectoryIterator( $wp_content_dir, FilesystemIterator::SKIP_DOTS );
 		$iterator       = new RecursiveIteratorIterator( $directory, RecursiveIteratorIterator::CHILD_FIRST );
 
 		// Regex to match.
diff --git a/inc/checks/class-constant-definition.php b/src/Check/Constant_Definition.php
similarity index 98%
rename from inc/checks/class-constant-definition.php
rename to src/Check/Constant_Definition.php
index 3eb648b..9799661 100644
--- a/inc/checks/class-constant-definition.php
+++ b/src/Check/Constant_Definition.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Confirms expected state of the %constant% constant.
diff --git a/inc/checks/class-core-update.php b/src/Check/Core_Update.php
similarity index 94%
rename from inc/checks/class-core-update.php
rename to src/Check/Core_Update.php
index 6d2bbbc..55d4c4d 100644
--- a/inc/checks/class-core-update.php
+++ b/src/Check/Core_Update.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Errors when new WordPress minor release is available; warns for major release.
diff --git a/inc/checks/class-core-verify-checksums.php b/src/Check/Core_Verify_Checksums.php
similarity index 92%
rename from inc/checks/class-core-verify-checksums.php
rename to src/Check/Core_Verify_Checksums.php
index 1e3f662..3b7abdf 100644
--- a/inc/checks/class-core-verify-checksums.php
+++ b/src/Check/Core_Verify_Checksums.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Verifies WordPress files against published checksums; errors on failure.
diff --git a/inc/checks/class-cron.php b/src/Check/Cron.php
similarity index 88%
rename from inc/checks/class-cron.php
rename to src/Check/Cron.php
index c70c5df..e83ace1 100644
--- a/inc/checks/class-cron.php
+++ b/src/Check/Cron.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 abstract class Cron extends Check {
 
diff --git a/inc/checks/class-cron-count.php b/src/Check/Cron_Count.php
similarity index 92%
rename from inc/checks/class-cron-count.php
rename to src/Check/Cron_Count.php
index 3922987..45d6dcf 100644
--- a/inc/checks/class-cron-count.php
+++ b/src/Check/Cron_Count.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Errors when there's an excess of %threshold_count% total cron jobs registered.
diff --git a/inc/checks/class-cron-duplicates.php b/src/Check/Cron_Duplicates.php
similarity index 96%
rename from inc/checks/class-cron-duplicates.php
rename to src/Check/Cron_Duplicates.php
index 8ba031d..08c1cbf 100644
--- a/inc/checks/class-cron-duplicates.php
+++ b/src/Check/Cron_Duplicates.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
 
diff --git a/inc/checks/class-file.php b/src/Check/File.php
similarity index 94%
rename from inc/checks/class-file.php
rename to src/Check/File.php
index 22aad9e..fc1b496 100644
--- a/inc/checks/class-file.php
+++ b/src/Check/File.php
@@ -1,6 +1,8 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
+
+use WP_CLI\Doctor\Check;
 
 /**
  * Check files on the filesystem.
diff --git a/inc/checks/class-file-contents.php b/src/Check/File_Contents.php
similarity index 96%
rename from inc/checks/class-file-contents.php
rename to src/Check/File_Contents.php
index 5530c8c..9ff823c 100644
--- a/inc/checks/class-file-contents.php
+++ b/src/Check/File_Contents.php
@@ -1,7 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
+use WP_CLI;
+use WP_CLI\Doctor\Check;
 use SplFileInfo;
 
 /**
diff --git a/inc/checks/class-file-type.php b/src/Check/File_Type.php
similarity index 94%
rename from inc/checks/class-file-type.php
rename to src/Check/File_Type.php
index 1d18e95..4070847 100644
--- a/inc/checks/class-file-type.php
+++ b/src/Check/File_Type.php
@@ -1,7 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
+use WP_CLI;
+use WP_CLI\Doctor\Check;
 use SplFileInfo;
 
 /**
diff --git a/inc/checks/class-language-update.php b/src/Check/Language_Update.php
similarity index 95%
rename from inc/checks/class-language-update.php
rename to src/Check/Language_Update.php
index f40ea8a..ec12882 100644
--- a/inc/checks/class-language-update.php
+++ b/src/Check/Language_Update.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Warns when there are language updates available.
diff --git a/inc/checks/class-option-value.php b/src/Check/Option_Value.php
similarity index 97%
rename from inc/checks/class-option-value.php
rename to src/Check/Option_Value.php
index c8cada2..f4b5ee5 100644
--- a/inc/checks/class-option-value.php
+++ b/src/Check/Option_Value.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Confirms the expected value of the '%option%' option.
diff --git a/inc/checks/class-php-in-upload.php b/src/Check/PHP_In_Upload.php
similarity index 94%
rename from inc/checks/class-php-in-upload.php
rename to src/Check/PHP_In_Upload.php
index a129d0f..cce7973 100644
--- a/inc/checks/class-php-in-upload.php
+++ b/src/Check/PHP_In_Upload.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 use RecursiveDirectoryIterator;
 use RecursiveIteratorIterator;
 
diff --git a/inc/checks/class-plugin.php b/src/Check/Plugin.php
similarity index 88%
rename from inc/checks/class-plugin.php
rename to src/Check/Plugin.php
index e7ac8d6..b759be9 100644
--- a/inc/checks/class-plugin.php
+++ b/src/Check/Plugin.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 abstract class Plugin extends Check {
 
diff --git a/inc/checks/class-plugin-active-count.php b/src/Check/Plugin_Active_Count.php
similarity index 92%
rename from inc/checks/class-plugin-active-count.php
rename to src/Check/Plugin_Active_Count.php
index 22e2cb5..6295664 100644
--- a/inc/checks/class-plugin-active-count.php
+++ b/src/Check/Plugin_Active_Count.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
 
@@ -17,8 +17,6 @@ class Plugin_Active_Count extends Plugin {
 	protected $threshold_count = 80;
 
 	public function run() {
-		$plugins = self::get_plugins();
-
 		$active = 0;
 		foreach ( self::get_plugins() as $plugin ) {
 			if ( 'active' === $plugin['status'] || 'active-network' === $plugin['status'] ) {
diff --git a/inc/checks/class-plugin-deactivated.php b/src/Check/Plugin_Deactivated.php
similarity index 94%
rename from inc/checks/class-plugin-deactivated.php
rename to src/Check/Plugin_Deactivated.php
index 24e5077..fa8ec01 100644
--- a/inc/checks/class-plugin-deactivated.php
+++ b/src/Check/Plugin_Deactivated.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Warns when greater than %threshold_percentage%% of plugins are deactivated.
diff --git a/inc/checks/class-plugin-status.php b/src/Check/Plugin_Status.php
similarity index 96%
rename from inc/checks/class-plugin-status.php
rename to src/Check/Plugin_Status.php
index 7c19c3d..fc3cd37 100644
--- a/inc/checks/class-plugin-status.php
+++ b/src/Check/Plugin_Status.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Errors if plugin '%name%' isn't in the expected state '%status%'.
diff --git a/inc/checks/class-plugin-update.php b/src/Check/Plugin_Update.php
similarity index 92%
rename from inc/checks/class-plugin-update.php
rename to src/Check/Plugin_Update.php
index 7966aa5..7ca47aa 100644
--- a/inc/checks/class-plugin-update.php
+++ b/src/Check/Plugin_Update.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Warns when there are plugin updates available.
diff --git a/inc/checks/class-theme-update.php b/src/Check/Theme_Update.php
similarity index 93%
rename from inc/checks/class-theme-update.php
rename to src/Check/Theme_Update.php
index 2db40ef..dd3a679 100644
--- a/inc/checks/class-theme-update.php
+++ b/src/Check/Theme_Update.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace runcommand\Doctor\Checks;
+namespace WP_CLI\Doctor\Check;
 
 use WP_CLI;
+use WP_CLI\Doctor\Check;
 
 /**
  * Warns when there are theme updates available.
diff --git a/inc/class-checks.php b/src/Checks.php
similarity index 89%
rename from inc/class-checks.php
rename to src/Checks.php
index dd13f13..d13f9b7 100644
--- a/inc/class-checks.php
+++ b/src/Checks.php
@@ -1,7 +1,8 @@
 <?php
 
-namespace runcommand\Doctor;
+namespace WP_CLI\Doctor;
 
+use Mustangostang\Spyc;
 use WP_CLI;
 use WP_CLI\Utils;
 
@@ -9,8 +10,8 @@ class Checks {
 
 	private static $instance;
 
-	private $checks  = array();
-	private $skipped = array();
+	private $checks         = array();
+	private $skipped_checks = array();
 
 	public static function get_instance() {
 		if ( ! isset( self::$instance ) ) {
@@ -29,7 +30,7 @@ public static function register_config( $file ) {
 			WP_CLI::error( 'Invalid configuration file.' );
 		}
 
-		$check_data = \Mustangostang\Spyc::YAMLLoad( file_get_contents( $file ) );
+		$check_data = Spyc::YAMLLoad( file_get_contents( $file ) );
 
 		if ( ! empty( $check_data['_']['inherit'] ) ) {
 			$inherited = $check_data['_']['inherit'];
@@ -60,7 +61,7 @@ public static function register_config( $file ) {
 				WP_CLI::error( "Check '{$check_name}' is missing 'class' or 'check'. Verify check registration." );
 			}
 
-			$class = ! empty( $check_args['check'] ) ? 'runcommand\Doctor\Checks\\' . $check_args['check'] : $check_args['class'];
+			$class = ! empty( $check_args['check'] ) ? 'WP_CLI\\Doctor\\Check\\' . $check_args['check'] : $check_args['class'];
 			if ( ! class_exists( $class ) ) {
 				WP_CLI::error( "Class '{$class}' for check '{$check_name}' doesn't exist. Verify check registration." );
 			}
@@ -91,7 +92,7 @@ public static function add_check( $name, $check ) {
 			}
 			$check = new $check();
 		}
-		if ( ! is_subclass_of( $check, 'runcommand\Doctor\Checks\Check' ) ) {
+		if ( ! is_subclass_of( $check, 'WP_CLI\\Doctor\\Check' ) ) {
 			$class = get_class( $check );
 			WP_CLI::error( "Class '{$class}' for check '{$name}' needs to extend Check base class. Verify check registration." );
 		}
@@ -124,7 +125,7 @@ public static function get_checks( $args = array() ) {
 	 * @param string $base Base path to prepend.
 	 */
 	private static function absolutize( $path, $base ) {
-		if ( ! empty( $path ) && ! \WP_CLI\Utils\is_path_absolute( $path ) ) {
+		if ( ! empty( $path ) && ! Utils\is_path_absolute( $path ) ) {
 			$path = $base . DIRECTORY_SEPARATOR . $path;
 		}
 		return $path;
diff --git a/inc/class-command.php b/src/Command.php
similarity index 99%
rename from inc/class-command.php
rename to src/Command.php
index 09be41e..9c76b7f 100644
--- a/inc/class-command.php
+++ b/src/Command.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace runcommand\Doctor;
+namespace WP_CLI\Doctor;
 
 use Exception;
 use RecursiveDirectoryIterator;
@@ -142,7 +142,7 @@ static function () use ( $name, $check, &$completed, &$progress ) {
 					}
 				);
 			} else {
-				$file_check = 'runcommand\Doctor\Checks\File';
+				$file_check = 'WP_CLI\Doctor\Check\File';
 				if ( is_a( $check, $file_check ) || is_subclass_of( $check, $file_check ) ) {
 					$file_checks[ $name ] = $check;
 				}
diff --git a/inc/class-exception.php b/src/Exception.php
similarity index 61%
rename from inc/class-exception.php
rename to src/Exception.php
index d50ac15..9e764a7 100644
--- a/inc/class-exception.php
+++ b/src/Exception.php
@@ -1,5 +1,5 @@
 <?php
 
-namespace runcommand\Doctor;
+namespace WP_CLI\Doctor;
 
 class Exception extends \Exception {}
diff --git a/wp-cli.yml b/wp-cli.yml
index 2c97a7d..5306364 100644
--- a/wp-cli.yml
+++ b/wp-cli.yml
@@ -1,2 +1,2 @@
 require:
-  - command.php
+  - doctor-command.php