diff --git a/lib/php/libsdk/SDK/Build/PGO/Abstracts/PHP.php b/lib/php/libsdk/SDK/Build/PGO/Abstracts/PHP.php
index d6090d6..d1d04e5 100644
--- a/lib/php/libsdk/SDK/Build/PGO/Abstracts/PHP.php
+++ b/lib/php/libsdk/SDK/Build/PGO/Abstracts/PHP.php
@@ -30,6 +30,8 @@ protected function setupPaths()
 		}
 	}
 
+	abstract public function getExeFilename() : string;
+
 	/* TODO Might be improved. */
 	public function isDist() : bool
 	{
@@ -96,7 +98,7 @@ public function getRootDir() : string
 	public function getVersion(bool $short = false) : string
 	{
 		$ret = NULL;
-		$cli = new CLI($this->conf, $this->scenario);
+		$cli = new CLI($this->conf);
 
 		$out = shell_exec($cli->getExeFilename() . " -n -v");
 
@@ -119,7 +121,7 @@ public function getVersion(bool $short = false) : string
 
 	public function isThreadSafe() : bool
 	{
-		$cli = new CLI($this->conf, $this->scenario);
+		$cli = new CLI($this->conf);
 
 		$out = shell_exec($cli->getExeFilename() . " -n -v");
 
diff --git a/lib/php/libsdk/SDK/Build/PGO/Abstracts/Server.php b/lib/php/libsdk/SDK/Build/PGO/Abstracts/Server.php
index 8a5cfd8..f8397f3 100644
--- a/lib/php/libsdk/SDK/Build/PGO/Abstracts/Server.php
+++ b/lib/php/libsdk/SDK/Build/PGO/Abstracts/Server.php
@@ -6,6 +6,9 @@
 
 abstract class Server
 {
+	protected $name;
+	protected $php;
+
 	public function getName() : string
 	{
 		return $this->name;
diff --git a/lib/php/libsdk/SDK/Build/PGO/Abstracts/TrainingCase.php b/lib/php/libsdk/SDK/Build/PGO/Abstracts/TrainingCase.php
index 522e740..8ca21ee 100644
--- a/lib/php/libsdk/SDK/Build/PGO/Abstracts/TrainingCase.php
+++ b/lib/php/libsdk/SDK/Build/PGO/Abstracts/TrainingCase.php
@@ -3,9 +3,10 @@
 namespace SDK\Build\PGO\Abstracts;
 
 use SDK\FileOps;
+use SDK\Build\PGO\Interfaces;
 use SDK\Build\PGO\Tool;
 
-abstract class TrainingCase
+abstract class TrainingCase implements Interfaces\TrainingCase
 {
 	use FileOps;
 
@@ -15,6 +16,9 @@ abstract class TrainingCase
 	protected $stat = array();
 	/** @var \SDK\Build\PGO\Config */
 	protected $conf;
+	protected $php;
+
+	abstract public function getName() : string;
 
 	public function getType() : string
 	{
diff --git a/lib/php/libsdk/SDK/Build/PGO/Controller.php b/lib/php/libsdk/SDK/Build/PGO/Controller.php
index 076a624..644e08b 100644
--- a/lib/php/libsdk/SDK/Build/PGO/Controller.php
+++ b/lib/php/libsdk/SDK/Build/PGO/Controller.php
@@ -52,7 +52,6 @@ protected function setupConfig($cmd)
 		switch ($cmd) {
 			default:
 				throw new Exception("Unknown action '{$cmd}'.");
-				break;
 			case "check_init":
 				$cnf = new PGOConfig(PGOConfig::MODE_CHECK_INIT);
 				break;
@@ -80,7 +79,6 @@ public function handle($force)
 		switch ($this->cmd) {
 			default:
 				throw new Exception("Unknown action '{$this->cmd}'.");
-				break;
 			case "init":
 				$lk = new Lock("pgo_init");
 				if (!$lk->locked()) {
@@ -242,7 +240,7 @@ public function up()
 		}
 		echo "\nStarting up PGO environment.\n\n";
 
-		foreach ($this->vitalizeSrv("all") as $srv) {
+		foreach ($this->vitalizeSrv() as $srv) {
 			$srv->up();
 			echo "\n";
 		}
@@ -260,7 +258,7 @@ public function down(bool $force = false)
 		/* XXX check it was started of course. */
 		echo "\nShutting down PGO environment.\n\n";
 
-		foreach ($this->vitalizeSrv("all") as $srv) {
+		foreach ($this->vitalizeSrv() as $srv) {
 			$srv->down($force);
 			echo "\n";
 		}
diff --git a/lib/php/libsdk/SDK/Build/PGO/Interfaces/Server.php b/lib/php/libsdk/SDK/Build/PGO/Interfaces/Server.php
index edfbf10..e71b2ae 100644
--- a/lib/php/libsdk/SDK/Build/PGO/Interfaces/Server.php
+++ b/lib/php/libsdk/SDK/Build/PGO/Interfaces/Server.php
@@ -12,4 +12,5 @@ public function init() : void;
 	public function up() : void;
 	public function down(bool $force = false) : void;
 	public function getName() : string;
+	public function getPhp();
 }
diff --git a/lib/php/libsdk/SDK/Build/PGO/TrainingCaseIterator.php b/lib/php/libsdk/SDK/Build/PGO/TrainingCaseIterator.php
index df186f3..82b06d7 100644
--- a/lib/php/libsdk/SDK/Build/PGO/TrainingCaseIterator.php
+++ b/lib/php/libsdk/SDK/Build/PGO/TrainingCaseIterator.php
@@ -50,6 +50,7 @@ protected function getHandlerFilename(string $base) : string
 		return $base . DIRECTORY_SEPARATOR . "TrainingCaseHandler.php";
 	}
 
+	#[\ReturnTypeWillChange]
 	public function current()
 	{
 		$base = $this->items[$this->idx];
@@ -73,21 +74,25 @@ public function current()
 		return $this->el;
 	}
 
+	#[\ReturnTypeWillChange]
 	public function next()
 	{
 		$this->idx++;
 	}
 
+	#[\ReturnTypeWillChange]
 	public function rewind()
 	{
 		$this->idx = 0;
 	}
 
+	#[\ReturnTypeWillChange]
 	public function valid()
 	{
 		return $this->idx < count($this->items);
 	}
 
+	#[\ReturnTypeWillChange]
 	public function key()
 	{
 		if (!is_object($this->el)) {
diff --git a/lib/php/libsdk/SDK/Config.php b/lib/php/libsdk/SDK/Config.php
index ccdf88e..49857db 100644
--- a/lib/php/libsdk/SDK/Config.php
+++ b/lib/php/libsdk/SDK/Config.php
@@ -12,7 +12,7 @@ class Config
 	protected static $depsUriScheme = "https";
 	protected static $depsBaseUri = "/~windows/php-sdk/deps";
 
-	/* protected static $sdkNugetFeedUrl = "http://127.0.0.1/sdk/nuget"; */
+	protected static $sdkNugetFeedUrl = "http://127.0.0.1/sdk/nuget"; // experimental?
 
 	protected static $knownBranches = array ();
 
@@ -28,7 +28,7 @@ public static function getDepsHost() : string
 		return self::$depsHost;
 	}/*}}}*/
 
-	public static function getDepsPort() : string
+	public static function getDepsPort() : int
 	{/*{{{*/
 		return self::$depsPort;
 	}/*}}}*/
@@ -264,6 +264,7 @@ public static function getCurrentBranchData() : array
 			throw new Exception("Unknown branch '$current_branch_name'");
 		}
 
+		$crt = null;
 		$cur_crt = Config::getCurrentCrtName();
 		if (count($branches[$current_branch_name]) > 1) {
 			if (NULL === $cur_crt) {
diff --git a/lib/php/libsdk/SDK/FileOps.php b/lib/php/libsdk/SDK/FileOps.php
index c31e437..b4577a4 100644
--- a/lib/php/libsdk/SDK/FileOps.php
+++ b/lib/php/libsdk/SDK/FileOps.php
@@ -90,6 +90,7 @@ protected function cp_or_mv(string $src, string $dst, callable $cb) : bool
 
 			if ($item->isFile()) {
 				if (!call_user_func($cb, $src_path, $dst_path)) {
+					assert(is_string($cb));
 					throw new Exception("Unable to $cb '$src_path' to '$dst_path'");
 				}
 			}