diff --git a/library/Tracks/EventStore/IRepository.php b/library/Tracks/EventStore/IRepository.php
new file mode 100644
index 0000000..a6a6b58
--- /dev/null
+++ b/library/Tracks/EventStore/IRepository.php
@@ -0,0 +1,12 @@
+<?php
+namespace Tracks\EventStore;
+use Tracks\Model\Guid;
+use Tracks\Model\AggregateRoot;
+
+interface IRepository
+{
+    public function load(Guid $guid);
+    public function save(AggregateRoot $aggregateRoot);
+    public function setSnapshotFrequency($numEvents);
+}
+
diff --git a/library/Tracks/EventStore/Repository.php b/library/Tracks/EventStore/Repository.php
index 3eb5f42..d43a035 100644
--- a/library/Tracks/EventStore/Repository.php
+++ b/library/Tracks/EventStore/Repository.php
@@ -26,9 +26,8 @@
  * @license   http://www.opensource.org/licenses/BSD-3-Clause BSD 3-Clause
  * @link      https://github.com/spiralout/Tracks
  */
-class Repository
+class Repository implements IRepository
 {
-
     const SNAPSHOT_FREQUENCY = 100;
 
     /**
diff --git a/library/Tracks/EventStore/SnapshotStorage/File.php b/library/Tracks/EventStore/SnapshotStorage/File.php
index a86ae85..69975a0 100644
--- a/library/Tracks/EventStore/SnapshotStorage/File.php
+++ b/library/Tracks/EventStore/SnapshotStorage/File.php
@@ -31,7 +31,6 @@
  */
 class File implements ISnapshotStore
 {
-
     /**
      * Constructor
      *
@@ -94,4 +93,4 @@ private function _getFilename(Guid $guid)
 
     /** @var string */
     private $_directory;
-}
\ No newline at end of file
+}
diff --git a/library/Tracks/Model/Entity.php b/library/Tracks/Model/Entity.php
index de36f7b..d0682a3 100644
--- a/library/Tracks/Model/Entity.php
+++ b/library/Tracks/Model/Entity.php
@@ -27,7 +27,6 @@
  */
 abstract class Entity
 {
-
     /**
      * Load an array of events onto this entity
      *
diff --git a/library/Tracks/Replay/EventStream/IEventStream.php b/library/Tracks/Replay/EventStream/IEventStream.php
new file mode 100644
index 0000000..ef86e49
--- /dev/null
+++ b/library/Tracks/Replay/EventStream/IEventStream.php
@@ -0,0 +1,7 @@
+<?php
+namespace Tracks\Replay;
+
+interface IEventStream extends \Iterator
+{
+    public function getDryRunInfo();
+}
diff --git a/library/Tracks/Replay/EventStream/ZendDb.php b/library/Tracks/Replay/EventStream/ZendDb.php
new file mode 100644
index 0000000..b9aecc2
--- /dev/null
+++ b/library/Tracks/Replay/EventStream/ZendDb.php
@@ -0,0 +1,115 @@
+<?php
+namespace Tracks\Replay\EventStream;
+
+class ZendDb implements IEventStream
+{
+    /** @staticvar int */
+    const BUFFER_SIZE = 100;
+
+    /** @var Zend_Db_Select */
+    private $_query;
+
+    /** @var array */
+    private $_rowBuffer = array();
+
+    /** @var int */
+    private $_cursor = 0;
+
+    /** @var int */
+    private $_offset = 0;
+
+    /** @var int */
+    private $_bufferSize;
+
+    /**
+     * Constructor
+     */
+    public function __construct(Zend_Db_Select $query, $bufferSize = self::BUFFER_SIZE)
+    {
+        assert('is_int($bufferSize)');
+
+        $this->_query = $query;
+        $this->_bufferSize = $bufferSize;
+    }
+
+    /**
+     * Get the current element
+     * @see Iterator::current()
+     */
+    public function current()
+    {
+        if (empty($this->_rowBuffer)) {
+            $this->loadMore();
+        }
+
+        return unserialize($this->_rowBuffer[$this->_cursor]['data']);
+    }
+
+    /**
+     * Get the key for the current element
+     * @see Iterator::key()
+     */
+    public function key()
+    {
+        return $this->_cursor;
+    }
+
+    /**
+     * Move the cursor to the next element
+     * @see Iterator::next()
+     */
+    public function next()
+    {
+        if (++$this->_cursor >= $this->_bufferSize) {
+            $this->loadMore();
+            $this->_cursor = 0;
+        }
+    }
+
+    /**
+     * Rewind the cursor to the first element
+     * @see Iterator::rewind()
+     */
+    public function rewind()
+    {
+        $this->_cursor = 0;
+
+        if (empty($this->_rowBuffer)) {
+            $this->loadMore();
+        }
+    }
+
+    /**
+     * Is the current key valid?
+     * @see Iterator::valid()
+     */
+    public function valid()
+    {
+        return $this->_cursor < count($this->_rowBuffer);
+    }
+
+    /**
+     * Get the SQL string for the current query
+     *
+     * @return string
+     */
+    public function getQueryAsString()
+    {
+        return $this->_query->assemble();
+    }
+
+    /**
+     * Load more rows from the database and put them in the buffer
+     */
+    private function loadMore()
+    {
+        $eventTable = new Zend_Db_Table('event');
+        $this->_rowBuffer = $eventTable
+            ->fetchAll(
+                $this->_query
+                ->limit(self::BUFFER_SIZE, $this->_offset)
+            )->toArray();
+
+        $this->_offset += self::BUFFER_SIZE;
+    }
+}
diff --git a/library/Tracks/Replay/EventStream/ZendDbBuilder.php b/library/Tracks/Replay/EventStream/ZendDbBuilder.php
new file mode 100644
index 0000000..57d8929
--- /dev/null
+++ b/library/Tracks/Replay/EventStream/ZendDbBuilder.php
@@ -0,0 +1,178 @@
+<?php
+namespace Tracks\Replay\EventStream;
+
+class ZendDbBuilder
+{
+    /** @var Zend_Db_Select */
+    private $_query;
+
+    /** @var array */
+    private $_eventClasses = array();
+
+    /** @var array */
+    private $_entities = array();
+
+    /** @var Zend_Date */
+    private $_startDate;
+
+    /** @var Zend_Date */
+    private $_endDate;
+
+    /**
+     * Start building an event stream
+     *
+     * @return Replay_EventStreamBuilder
+     */
+    public static function start()
+    {
+        return new self;
+    }
+
+    /**
+     * Stream all events
+     *
+     * @return Replay_EventStreamBuilder
+     */
+    public function withAllEvents()
+    {
+        $this->_eventClasses = array();
+
+        return $this;
+    }
+
+    /**
+     * Stream a specific event class
+     *
+     * @param string $eventClass
+     * @return Replay_EventStreamBuilder
+     */
+    public function withEvent($eventClass)
+    {
+        assert('is_string($eventClass)');
+
+        $this->_eventClasses[] = $eventClass;
+
+        return $this;
+    }
+
+    /**
+     * Stream from all entities
+     *
+     * @return Replay_EventStreamBuilder
+     */
+    public function fromAllEntities()
+    {
+        $this->_entities = array();
+
+        return $this;
+    }
+
+    /**
+     * Get events that belong to an entity
+     *
+     * @param string $guid
+     * @return Replay_EventStreamBuilder
+     */
+    public function fromEntity($guid)
+    {
+        assert('is_string($guid)');
+
+        $this->_entities[] = $guid;
+
+        return $this;
+    }
+
+    /**
+     * Stream events for all time
+     *
+     * @return Replay_EventStreamBuilder
+     */
+    public function forAllTime()
+    {
+        $this->_startDate = null;
+        $this->_endDate = null;
+
+        return $this;
+    }
+
+    /**
+     * Specify a date range from which to select events
+     * Only one date range may be specified
+     *
+     * @param Zend_Date $startDate
+     * @param Zend_Date $endDate
+     * @return Replay_EventStreamBuilder
+     */
+    public function inDateRange(Zend_Date $startDate, Zend_Date $endDate)
+    {
+        $this->_startDate = $startDate;
+        $this->_endDate = $endDate;
+
+        return $this;
+    }
+
+    /**
+     * Get the Replay_EventStream object
+     *
+     * @return Replay_EventStream
+     */
+    public function build()
+    {
+        $this->buildBaseQuery();
+        $this->buildEventsQuery();
+        $this->buildDateRangeQuery();
+        $this->buildEntitiesQuery();
+
+        return new Replay_EventStream($this->_query);
+    }
+
+    /**
+     * Build the base query to load events
+     */
+    private function buildBaseQuery()
+    {
+        $eventTable = new Table_Event;
+        $this->_query = $eventTable
+            ->select()
+            ->from('event', '*')
+            ->setIntegrityCheck(false)
+            ->order('date_created ASC')
+            ->order('event.id');
+    }
+
+    /**
+     * Build the event class filter part of the query
+     */
+    private function buildEventsQuery()
+    {
+        if (count($this->_eventClasses) > 0) {
+            $this->_query->where(implode('OR', array_map(function($x) { return " data LIKE '%{$x}%' "; }, $this->_eventClasses)));
+        }
+    }
+
+    /**
+     * Build the entity guid filter part of the query
+     */
+    private function buildEntitiesQuery()
+    {
+        if (count($this->_entities) > 0) {
+            $this->_query
+                ->join('event_provider', 'event.event_provider_id = event_provider.id')
+                ->where(new Zend_Db_Expr("event_provider.guid IN (". implode(',', array_map(function($x) { return "'{$x}'"; }, $this->_entities)) .")"));
+        }
+    }
+
+    /**
+     * Build the date range filter part of the query
+     */
+    private function buildDateRangeQuery()
+    {
+        if ($this->_startDate) {
+            $this->_query->where('date_created >= ?', $this->_startDate->toString('Y-m-d'));
+        }
+
+        if ($this->_endDate) {
+            $this->_query->where('date_created <= ?', $this->_endDate->toString('Y-m-d'));
+        }
+    }
+}
diff --git a/library/Tracks/Replay/Player.php b/library/Tracks/Replay/Player.php
new file mode 100644
index 0000000..2f2be71
--- /dev/null
+++ b/library/Tracks/Replay/Player.php
@@ -0,0 +1,56 @@
+<?php
+namespace Tracks\Replay;
+use Tracks\Replay\Router\IRouter;
+use Tracks\Replay\EventStream\IEventStream;
+use Tracks\UnitOfWork\ITransaction;
+
+class Player
+{
+    /** @var \Tracks\Replay\Router\IRouter */
+    private $_router;
+
+    /** @var \Tracks\Replay\EventStream\IEventStream */
+    private $_stream;
+
+    public function __construct(IRouter $router, IEventStream $stream)
+    {
+        $this->_router = $router;
+        $this->_stream = $stream;
+    }
+
+    /**
+     * Play the event stream and execute event handlers
+     *
+     * @param ITransaction $transaction
+     */
+    public function play(ITransaction $transaction = NULL)
+    {
+        $transaction and $transaction->begin();
+
+        try {
+            foreach ($this->_stream as $event) {
+                $this->_router->route($event);
+            }
+        } catch (Exception $e) {
+            $transaction and $transaction->rollback();
+            throw $e;
+        }
+
+        $transaction and $transaction->commit();
+    }
+
+    /**
+     * Print debug information about what would happen if current stream was played
+     */
+    public function dryRun()
+    {
+        echo $this->_stream->getDryRunInfo() . PHP_EOL . PHP_EOL;
+
+        foreach ($this->_stream as $event) {
+            $handlers = $this->_router->getHandlersRegisteredFor(get_class($event));
+            echo get_class($event) .': '. $event->guid .': ('. implode(',', array_map('get_class', $handlers)) .')'. PHP_EOL;
+        }
+
+        echo PHP_EOL;
+    }
+}
diff --git a/library/Tracks/Replay/Router/DirectRouter.php b/library/Tracks/Replay/Router/DirectRouter.php
new file mode 100644
index 0000000..ce49875
--- /dev/null
+++ b/library/Tracks/Replay/Router/DirectRouter.php
@@ -0,0 +1,50 @@
+<?php
+namespace Tracks\Replay\Router;
+use Tracks\Event;
+use Tracks\EventHandler\IEventHandler;
+
+class DirectRouter implements IRouter
+{
+    /** @var array */
+    private $_handlers = array();
+
+    public function route(Event\Base $event)
+    {
+        if (isset($this->_handlers[get_class($event)])) {
+            foreach ($this->_handlers[get_class($event)] as $handler) {
+                if (is_string($handler)) {
+                    $handler = new $handler;
+                }
+
+                $handler->handle($event);
+            }
+        }
+    }
+
+    public function addHandler($eventClass, $handler)
+    {
+        assert('is_string($eventClass)');
+        assert('is_string($handler) or is_object($handler)');
+
+        if (is_object($handler)
+            && !($handler instanceof IEventHandler)
+        ) {
+            throw new LogicException('Event handlers must implement \Tracks\EventHandler\IEventHandler');
+        }
+
+        if (!isset($this->_handlers[$eventClass])) {
+            $this->_handlers[$eventClass] = array();
+        }
+
+        $this->_handlers[$eventClass][] = $handler;
+
+        return $this;
+    }
+
+    public function getHandlersRegisteredFor($eventClass)
+    {
+        assert('is_string($eventClass)');
+
+        return (isset($this->_handlers[$eventClass]) ? $this->_handlers[$eventClass] : array());
+    }
+}
diff --git a/library/Tracks/Replay/Router/IRouter.php b/library/Tracks/Replay/Router/IRouter.php
new file mode 100644
index 0000000..e820d99
--- /dev/null
+++ b/library/Tracks/Replay/Router/IRouter.php
@@ -0,0 +1,10 @@
+<?php
+namespace Tracks\Replay\Router;
+use Tracks\Event;
+
+interface IRouter
+{
+    public function route(Event\Base $event);
+    public function addHandler($eventClass, $handler);
+    public function getHandlersRegisteredFor($eventClass);
+}
diff --git a/library/Tracks/UnitOfWork/ITransaction.php b/library/Tracks/UnitOfWork/ITransaction.php
new file mode 100644
index 0000000..8fb4295
--- /dev/null
+++ b/library/Tracks/UnitOfWork/ITransaction.php
@@ -0,0 +1,9 @@
+<?php
+namespace Tracks\UnitOfWork;
+
+interface ITransaction
+{
+    public function begin();
+    public function rollback();
+    public function commit();
+}
diff --git a/library/Tracks/UnitOfWork/IUnitOfWork.php b/library/Tracks/UnitOfWork/IUnitOfWork.php
new file mode 100644
index 0000000..d6d7bc3
--- /dev/null
+++ b/library/Tracks/UnitOfWork/IUnitOfWork.php
@@ -0,0 +1,9 @@
+<?php
+namespace Tracks\UnitOfWork;
+use Tracks\Model\AggregateRoot;
+
+interface IUnitOfWork
+{
+    public function registerSave(AggregateRoot $aggregateRoot);
+    public function commit();
+}
diff --git a/library/Tracks/UnitOfWork/UnitOfWork.php b/library/Tracks/UnitOfWork/UnitOfWork.php
new file mode 100644
index 0000000..2358115
--- /dev/null
+++ b/library/Tracks/UnitOfWork/UnitOfWork.php
@@ -0,0 +1,36 @@
+<?php
+namespace Tracks\UnitOfWork;
+use Tracks\EventStore\IRepository;
+use Tracks\Model\AggregateRoot;
+
+class UnitOfWork implements IUnitOfWork
+{
+    private $_repository;
+    private $_registeredSaves = array();
+
+    public function __construct(IRepository $repository)
+    {
+        $this->_repository = $repository;
+    }
+
+    public function registerSave(AggregateRoot $aggregateRoot)
+    {
+        $this->_registeredSaves[] = $aggregateRoot;
+    }
+
+    public function commit(ITransaction $transaction = NULL)
+    {
+        $transaction and $transaction->begin();
+
+        try {
+            foreach ($this->_registeredSaves as $aggregateRoot) {
+                $this->_repository->save($aggregateRoot);
+            }
+        } catch (Exception $e) {
+            $transaction and $transaction->rollback();
+            throw $e;
+        }
+
+        $transaction and $transaction->commit();
+    }
+}