diff --git a/website/lib/BashInterpreter.php b/website/lib/BashInterpreter.php
new file mode 100644
index 0000000..793eb82
--- /dev/null
+++ b/website/lib/BashInterpreter.php
@@ -0,0 +1,49 @@
+<?php
+
+class BashInterpreter {
+    public static function matchCommand($text, $command) {
+        $command = str_replace("/", "\/", $command);
+        preg_match_all("/".$command." .*[;|$|\r\n]/", $text, $matches);
+        return $matches[0];
+    }
+
+    public static function matchFlag($command, $flag) {
+        $flag = str_replace("/", "\/", $flag);
+        preg_match_all("/".$flag." ([a-zA-Z0-9.~\-\/]*)/", $command, $matches);
+        return $matches[1];
+    }
+
+    public static function removeFlagFromCommand($text, $full_command, $full_flag) {
+        $replaced = str_replace($full_flag, "", $full_command);
+        $text = str_replace($full_command, $replaced, $text);
+        return $text;
+    }
+
+    public static function addFlagToCommands($text, $command, $full_flag) {
+        return str_replace($command, $command." ".$full_flag, $text);
+    }
+
+    public static function removeFlagFromCommands($text, $command, $full_flag) {
+        foreach(BashInterpreter::matchCommand($text, $command) as $match) {
+            $text = BashInterpreter::removeFlagFromCommand($text, $match, $full_flag);
+        }
+        return $text;
+    }
+
+    public static function removeCommand($text, $full_command) {
+        return str_replace($full_command, "", $text);
+    }
+
+    public static function normalizeDir($dir) {
+        $dir = str_replace("//", "/", $dir);
+        $dir = str_replace("/./", "/", $dir);
+        $dir = preg_replace("#^./#", "", $dir);
+        $dir = str_replace("~", '$HOME', $dir);
+        $dir = preg_replace("#/$#", "", $dir);
+        return $dir;
+    }
+
+    public static function sameDir($dir1, $dir2) {
+        return BashInterpreter::normalizeDir($dir1) == BashInterpreter::normalizeDir($dir2);
+    }
+}
diff --git a/website/lib/DB/Mode.php b/website/lib/DB/Mode.php
new file mode 100644
index 0000000..5bd4b0f
--- /dev/null
+++ b/website/lib/DB/Mode.php
@@ -0,0 +1,30 @@
+<?php
+
+class Mode {
+
+    // db: awfy_mode
+    function __construct($id) {
+        $this->id = $id;
+    }
+
+    function vendor() {
+        $qMode = mysql_query("SELECT vendor_id
+                              FROM awfy_mode
+                              WHERE id = {$this->id}");
+        $mode = mysql_fetch_object($qMode);
+        return $mode->vendor_id;
+    }
+
+    function mode() {
+        $qMode = mysql_query("SELECT mode
+                              FROM awfy_mode
+                              WHERE id = {$this->id}");
+        $mode = mysql_fetch_object($qMode);
+        return $mode->mode;
+    }
+
+    function id() {
+        return $this->id;
+    }
+}
+
diff --git a/website/lib/DB/QueuedTask.php b/website/lib/DB/QueuedTask.php
new file mode 100644
index 0000000..7cc4ca8
--- /dev/null
+++ b/website/lib/DB/QueuedTask.php
@@ -0,0 +1,30 @@
+<?php
+
+class QueuedTask {
+
+    // db: control_task_queue
+    function __construct($id) {
+        $this->id = $id;
+    }
+
+    function setBusy() {
+        mysql_query("UPDATE control_task_queue SET busy = 1 WHERE id = {$this->id}") or die(mysql_error());
+    }
+
+    function setFinished() {
+        mysql_query("DELETE FROM control_task_queue WHERE id = {$this->id}");
+    }
+
+    function task() {
+        $qTask = mysql_query("SELECT task
+                              FROM control_task_queue
+                              WHERE id = {$this->id}");
+        $task = mysql_fetch_object($qTask);
+        return $task->task;
+    }
+
+    function id() {
+        return $this->id;
+    }
+}
+
diff --git a/website/lib/DB/TaskQueue.php b/website/lib/DB/TaskQueue.php
new file mode 100644
index 0000000..2484772
--- /dev/null
+++ b/website/lib/DB/TaskQueue.php
@@ -0,0 +1,42 @@
+<?php
+
+require_once("QueuedTask.php");
+
+class TaskQueue {
+
+    // db: control_task_queue
+    function __construct($unit_id) {
+        $this->unit_id = $unit_id;
+    }
+
+    // Returns if there is a task still running. 
+    function has_active_task() {
+        $qTask = mysql_query("SELECT *
+                              FROM control_task_queue
+                              WHERE control_unit_id = {$this->unit} AND busy = 1
+                              ORDER BY id LIMIT 1");
+        return mysql_num_rows($qTask) != 0;
+    }
+
+    function has_queued_tasks() {
+        $qTask = mysql_query("SELECT *
+                              FROM control_task_queue
+                              WHERE control_unit_id = $unit and busy = 0
+                              ORDER BY id LIMIT 1");
+        return mysql_num_rows($qTask) != 0;
+
+    }
+
+    function pop() {
+        $qTask = mysql_query("SELECT id
+                              FROM control_task_queue
+                              WHERE control_unit_id = $unit and busy = 0
+                              ORDER BY id LIMIT 1");
+        $task = mysql_fetch_object($qTask);
+
+        $task = QueuedTask($task->id);
+        $task->setBusy();
+
+        return $task;
+    }
+}
diff --git a/website/lib/ManipulateTask.php b/website/lib/ManipulateTask.php
new file mode 100644
index 0000000..ebba0f1
--- /dev/null
+++ b/website/lib/ManipulateTask.php
@@ -0,0 +1,137 @@
+<?php
+
+include_once "BashInterpreter.php";
+include_once "Task.php";
+
+class ManipulateTask extends Task {
+
+    public function update_benchmarks($new_benchmarks) {
+        //Note: Impossible to add new benchmarks using this command. Only possible to prune ones.
+        $old_benchmarks = $this->benchmarks();
+        $removed_benchmarks = array_diff($old_benchmarks, $new_benchmarks);
+        foreach($removed_benchmarks as $removed) {
+            $this->task = BashInterpreter::removeFlagFromCommands($this->task, "python execute.py", "-b ".$removed);
+        }
+
+        $this->optimize();
+    }
+
+    public function update_configs($new_configs) {
+        //Note: Impossible to add new configs using this command. Only possible to prune ones.
+        $old_configs= $this->configs();
+        $removed_configs = array_diff($old_configs, $new_configs);
+        foreach($removed_configs as $removed) {
+            $this->task = BashInterpreter::removeFlagFromCommands($this->task, "python execute.py", "-c ".$removed);
+        }
+
+        $this->optimize();
+    }
+
+    public function update_engines($new_engines) {
+        //Note: Impossible to add new engines using this command. Only possible to prune ones.
+        $old_engines = $this->engines();
+        $removed_engines = array_diff($old_engines, $new_engines);
+
+        // Build engines
+        $commands = BashInterpreter::matchCommand($this->task, "python build.py");
+        foreach ($commands as $command) {
+            $source_matches = BashInterpreter::matchFlag($command, "-s");
+            $engine = $this->source_rules()[$source_matches[0]];
+            print_r($removed_engines);
+            if (in_array($engine, $removed_engines)) {
+                $this->removeBuildOrDownloadCommand($command);
+            }
+        }
+
+        $this->optimize();
+    }
+
+    public function update_modes($modes) {
+        $engines = [];
+        $configs = [];
+        $mode_rules = array_flip($this->mode_rules());
+
+        foreach ($modes as $mode) {
+            $rule = $mode_rules[$mode];
+            $rule = split(",", $rule);
+            $engines[] = $rule[0];
+            $configs[] = $rule[1];
+        }
+
+        $this->update_engines($engines);
+        $this->update_configs($configs);
+    }
+
+    public function setTipRevision() {
+        $this->removeRevisionInfo();
+    }
+
+    public function setRevision($new_revision) {
+        $this->removeRevisionInfo();
+        $this->task = BashInterpreter::addFlagToCommands($this->task, "python build.py", "-r ".$new_revision);
+    }
+
+    private function removeRevisionInfo() {
+        $commands = BashInterpreter::matchCommand($this->task, "python download.py");
+        if (count($commands) != 0)
+            throw new Exception("Not yet supported to specify revision for downloaded builds.");
+
+        $commands = BashInterpreter::matchCommand($this->task, "python build.py");
+        foreach ($commands as $command) {
+            $revision_matches = BashInterpreter::matchFlag($command, "-r");
+            for ($revision_matches as $revision) {
+                $this->task = BashInterpreter::removeFlagFromCommand($this->task, $command, "-r ".$revision);
+            }
+        }
+    }
+
+    private function removeBuildOrDownloadCommand($command) {
+        $output_matches = BashInterpreter::matchFlag($command, "-o");
+        $this->task = BashInterpreter::removeCommand($this->task, $command);
+        if (count($output_matches) == 0) {
+            // If there was no output dir specified, remove all executes where no engine dir is given.
+            // or where the default 'output' dir is specified. 
+            $commands = BashInterpreter::matchCommand($this->task, "python execute.py");
+            foreach ($commands as $command) {
+                $engine_matches = BashInterpreter::matchFlag($command, "-e");
+                if (count($engine_matches) == 0) {
+                    $this->task = BashInterpreter::removeCommand($this->task, $command);
+                    continue;
+                } 
+
+                foreach ($engine_matches as $engineDir) {
+                    if (BashInterpreter::sameDir($engineDir, "output")) {
+                        $this->task = BashInterpreter::removeFlagFromCommand($this->task, $command, "-e ".$engineDir);
+                        if (count($engine_matches) == 1)
+                            $this->task = BashInterpreter::removeCommand($this->task, $command);
+                    }
+                }
+            }
+        } else {
+            $outputDir = $output_matches[0];
+            $commands = BashInterpreter::matchCommand($this->task, "python execute.py");
+            foreach ($commands as $command) {
+                $engine_matches = BashInterpreter::matchFlag($command, "-e");
+                foreach ($engine_matches as $engineDir) {
+                    if (BashInterpreter::sameDir($engineDir, $outputDir)) {
+                        $this->task = BashInterpreter::removeFlagFromCommand($this->task, $command, "-e ".$engineDir);
+                        if (count($engine_matches) == 1)
+                            $this->task = BashInterpreter::removeCommand($this->task, $command);
+                    }
+                }
+            }
+
+        }
+    }
+
+    private function optimize() {
+        $commands = BashInterpreter::matchCommand($this->task, "python execute.py");
+        foreach ($commands as $command) {
+            // Any execute without benchmarks don't need to get run.
+            if (count(BashInterpreter::matchFlag($command, "-b")) == 0)
+                $this->task = BashInterpreter::removeCommand($this->task, $command);
+
+        }
+    }
+}
+
diff --git a/website/lib/RetriggerController.php b/website/lib/RetriggerController.php
new file mode 100644
index 0000000..c711c02
--- /dev/null
+++ b/website/lib/RetriggerController.php
@@ -0,0 +1,65 @@
+<?php
+
+require_once("ManipulateTask.php");
+require_once("DB/Mode.php");
+
+class RetriggerController {
+
+    public function __construct() {
+        $this->tasks = [];
+        $this->unit_id = 0;
+    }
+
+    public static function fromUnit($unit_id) {
+        $retrigger = new RetriggerController();
+        $retrigger->unit_id = $unit_id;
+
+		$qTask = mysql_query("SELECT * FROM control_tasks WHERE control_unit_id = $unit_id");
+        while ($task = mysql_fetch_object($qTask)) {
+            $task = new ManipulateTask($task);
+            $retrigger->tasks[] = $task;
+        }
+        return $retrigger;
+    }
+
+    public static function fromMachine($machine, $mode_id = 0) {
+        $retrigger = new RetriggerController();
+        $mode = new Mode($mode_id);
+
+		$qTask = mysql_query("SELECT * FROM control_tasks WHERE machine_id = $machine");
+        while ($task = mysql_fetch_object($qTask)) {
+            if (!($mode_id == 0 || $task->mode_id == 0 || $task->mode_id == $mode_id))
+                continue;
+
+            $task = new ManipulateTask($task);
+            if ($mode_id != 0)
+                $task->update_modes($mode->mode());
+
+            $retrigger->tasks[] = $task;
+
+            if ($this->unit_id != 0 && $this->unit_id != $task->control_unit_id)
+                throw new Exception("Only one machine allowed.");
+
+            $this->unit_id = $task->control_unit_id;
+        }
+        return $retrigger;
+    }
+
+    public function setRevision($revision) {
+        foreach ($this->tasks as $task) {
+            $task->setRevision($revision);
+        }
+    }
+
+    public function enqueue() {
+        if ($this->unit_id == 0)
+            throw new Exception("No control_unit specified.");
+
+        foreach ($this->tasks as $task) {
+			mysql_query("INSERT INTO control_task_queue
+                         (control_unit_id, task)
+                         VALUES ({$this->unit_id}, '".mysql_escape_string($task)."')");
+        }
+    }
+}
+
diff --git a/website/lib/Task.php b/website/lib/Task.php
new file mode 100644
index 0000000..96048ae
--- /dev/null
+++ b/website/lib/Task.php
@@ -0,0 +1,101 @@
+<?php
+
+class Task {
+
+    // The build function contains the 'source' it needs to fetch
+    // the code from. We need to know which source is which engine.
+    // This makes the transition from source to engine. 
+    // Note: an engine can have multiple sources.
+    public function source_rules() {
+        return [
+            "mozilla" => "firefox",
+            "v8" => "chrome",
+            "webkit" => "webkit"
+        ];
+    }
+
+    // The execute function looks at engine+config to decide which
+    // mode it should send this data to. These contain the default rules.
+    // Though it is possible to add some extra rules in the task
+    // itself. These are not accounted for (TODO).
+    public function mode_rules() {
+        return [
+            "firefox,default" => "jmim",
+            "firefox,noasmjs" => "noasmjs",
+            "firefox,unboxedobjects" => "unboxedobjects",
+            "firefox,testbedregalloc" => "testbed",
+            "chrome,default" => "v8",
+            "chrome,turbofan" => "v8-turbofan",
+            "webkit,default" => "jsc",
+            "native,default" => "clang",
+            "servo,default" => "servo"
+        ];
+    }
+
+    public function __construct($task) {
+        $this->task = $task;
+    }
+
+    public function task() {
+        return $this->task;
+    }
+
+    public function configs() {
+        $configs = [];
+        $commands = BashInterpreter::matchCommand($this->task, "python execute.py");
+        foreach ($commands as $command) {
+            $config_matches = BashInterpreter::matchFlag($command, "-c");
+            foreach ($config_matches as $match) {
+                $configs[] = $match;
+            }
+        }
+        return array_unique($configs);
+    }
+
+    public function engines() {
+        $engines = [];
+
+        // Fetch all engines that have been build.
+        $commands = BashInterpreter::matchCommand($this->task, "python build.py");
+        foreach ($commands as $command) {
+            $source_matches = BashInterpreter::matchFlag($command, "-s");
+            if (count($source_matches) != 1)
+                throw new Error("Expected one match.");
+
+            $engines[] = $this->source_rules()[$source_matches[0]];
+        }
+
+        // Fetch all engines that have been downloaded.
+        // TODO.
+        return array_unique($engines);
+    }
+
+    public function modes() {
+        $configs = $this->configs();
+        $engines = $this->engines();
+        $mode_rules = $this->mode_rules();
+
+        $modes = [];
+        foreach ($configs as $config) {
+            foreach ($engines as $engine) {
+                $rule = $engine.",".$config;
+                if (isset($mode_rules[$rule])) {
+                    $modes[] = $mode_rules[$rule];
+                }
+            }
+        }
+        return $modes;
+    }
+
+    public function benchmarks() {
+        $configs = [];
+        $commands = BashInterpreter::matchCommand($this->task, "python execute.py");
+        foreach ($commands as $command) {
+            $config_matches = BashInterpreter::matchFlag($command, "-b");
+            foreach ($config_matches as $match) {
+                $configs[] = $match;
+            }
+        }
+        return array_unique($configs);
+    }
+}
diff --git a/website/task.php b/website/task.php
index 4408ddc..4411321 100644
--- a/website/task.php
+++ b/website/task.php
@@ -5,48 +5,36 @@
 
 require_once("internals.php");
 
+require_once("lib/RetriggerController.php");
+require_once("lib/DB/TaskQueue.php");
+require_once("lib/DB/QueuedTask.php");
+
 init_database();
 
-if (isset($_GET["unit"]) && is_numeric($_GET["unit"])) {
-	$unit = (int)$_GET["unit"];
+if ($unit = GET_int("unit")) {
 
-	$qTask = mysql_query("SELECT *
-                          FROM control_task_queue
-                          WHERE control_unit_id = $unit AND busy = 1
-                          ORDER BY id LIMIT 1");
-	if (mysql_num_rows($qTask) != 0) {
+    $queue = new TaskQueue($unit);
+    if ($queue->has_active_task())
 		slack("requesting new task, while old task is still running!");
+
+    if (!$queue->has_queued_tasks())
+        $retrigger = RetriggerController::fromUnit($unit);
+        $retrigger->enqueue();
 	}
 
+    $task = $queue->pop();
 
-    $qTask = mysql_query("SELECT *
-                          FROM control_task_queue
-                          WHERE control_unit_id = $unit and busy = 0
-                          ORDER BY id LIMIT 1");
-    if (mysql_num_rows($qTask) == 0) {
-		$qTask = mysql_query("SELECT task FROM control_tasks WHERE control_unit_id = $unit");
-        while ($task = mysql_fetch_object($qTask)) {
-			mysql_query("INSERT INTO control_task_queue
-                         (control_unit_id, task)
-                         VALUES ($unit, '".mysql_escape_string($tasks->task)."')");
-		}
-	}
-
-    $qTask = mysql_query("SELECT *
-                          FROM control_task_queue
-                          WHERE control_unit_id = $unit and busy = 0
-                          ORDER BY id LIMIT 1");
-	$task = mysql_fetch_object($qTask);
-	echo json_encode(Array("task" => $task->task,
-                           "id" => $task->id));
-
-	mysql_query("UPDATE control_task_queue SET busy = 1 WHERE id = ".$task->id);
+	echo json_encode([
+        "task" => $task->task(),
+        "id" => $task->id()
+    ]);
 
     die();
 
-} else if (isset($_GET["finish"]) && is_numeric($_GET["finish"])) {
-	$task_id = $_GET["finish"];
-	mysql_query("DELETE FROM control_task_queue WHERE id = ".$task_id);
+} else if ($task_id = GET_int("finish")) {
+
+    $task = QueuedTask($task_id);
+    $task->setFinished();
 
 	die();
 }