diff --git a/src/Model/AbstractDao.php b/src/Model/AbstractDao.php
index 4c99cfd..a7fe1d1 100644
--- a/src/Model/AbstractDao.php
+++ b/src/Model/AbstractDao.php
@@ -4,6 +4,7 @@ namespace Pairity\Model;
 
 use Pairity\Contracts\ConnectionInterface;
 use Pairity\Contracts\DaoInterface;
+use Pairity\Orm\UnitOfWork;
 
 abstract class AbstractDao implements DaoInterface
 {
@@ -92,6 +93,13 @@ abstract class AbstractDao implements DaoInterface
 
     public function findById(int|string $id): ?AbstractDto
     {
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            $managed = $uow->get(static::class, (string)$id);
+            if ($managed instanceof AbstractDto) {
+                return $managed;
+            }
+        }
         return $this->findOneBy([$this->getPrimaryKey() => $id]);
     }
 
@@ -136,6 +144,36 @@ abstract class AbstractDao implements DaoInterface
     /** @param array<string,mixed> $data */
     public function update(int|string $id, array $data): AbstractDto
     {
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            // Defer execution; return a synthesized DTO
+            $existing = $this->findById($id);
+            if (!$existing && empty($data)) {
+                throw new \InvalidArgumentException('No data provided to update and record not found');
+            }
+            $toStore = $this->prepareForUpdate($data);
+            $self = $this;
+            $conn = $this->connection;
+            $uow->enqueue($conn, function () use ($self, $id, $toStore) {
+                UnitOfWork::suspendDuring(function () use ($self, $id, $toStore) {
+                    // execute real update now
+                    $sets = [];
+                    $params = [];
+                    foreach ($toStore as $col => $val) {
+                        $sets[] = "$col = :set_$col";
+                        $params["set_$col"] = $val;
+                    }
+                    $params['pk'] = $id;
+                    $sql = 'UPDATE ' . $self->getTable() . ' SET ' . implode(', ', $sets) . ' WHERE ' . $self->getPrimaryKey() . ' = :pk';
+                    $self->getConnection()->execute($sql, $params);
+                });
+            });
+            $base = $existing ? $existing->toArray(false) : [];
+            $pk = $this->getPrimaryKey();
+            $result = array_merge($base, $data, [$pk => $id]);
+            return $this->hydrate($this->castRowFromStorage($result));
+        }
+
         if (empty($data)) {
             $existing = $this->findById($id);
             if ($existing) return $existing;
@@ -153,7 +191,6 @@ abstract class AbstractDao implements DaoInterface
         $this->connection->execute($sql, $params);
         $updated = $this->findById($id);
         if ($updated === null) {
-            // As a fallback, hydrate using provided data + id
             $pk = $this->getPrimaryKey();
             return $this->hydrate($this->castRowFromStorage(array_merge($data, [$pk => $id])));
         }
@@ -162,6 +199,15 @@ abstract class AbstractDao implements DaoInterface
 
     public function deleteById(int|string $id): int
     {
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            $self = $this; $conn = $this->connection; $theId = $id;
+            $uow->enqueue($conn, function () use ($self, $theId) {
+                UnitOfWork::suspendDuring(function () use ($self, $theId) { $self->deleteById($theId); });
+            });
+            // deferred; immediate affected count unknown
+            return 0;
+        }
         if ($this->hasSoftDeletes()) {
             $columns = $this->softDeleteConfig();
             $deletedAt = $columns['deletedAt'] ?? 'deleted_at';
@@ -176,6 +222,14 @@ abstract class AbstractDao implements DaoInterface
     /** @param array<string,mixed> $criteria */
     public function deleteBy(array $criteria): int
     {
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            $self = $this; $conn = $this->connection; $crit = $criteria;
+            $uow->enqueue($conn, function () use ($self, $crit) {
+                UnitOfWork::suspendDuring(function () use ($self, $crit) { $self->deleteBy($crit); });
+            });
+            return 0;
+        }
         if ($this->hasSoftDeletes()) {
             [$where, $bindings] = $this->buildWhere($criteria);
             if ($where === '') { return 0; }
@@ -200,6 +254,16 @@ abstract class AbstractDao implements DaoInterface
      */
     public function updateBy(array $criteria, array $data): int
     {
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            if (empty($data)) { return 0; }
+            $self = $this; $conn = $this->connection; $crit = $criteria; $payload = $this->prepareForUpdate($data);
+            $uow->enqueue($conn, function () use ($self, $crit, $payload) {
+                UnitOfWork::suspendDuring(function () use ($self, $crit, $payload) { $self->updateBy($crit, $payload); });
+            });
+            // unknown affected rows until commit
+            return 0;
+        }
         if (empty($data)) {
             return 0;
         }
@@ -457,6 +521,14 @@ abstract class AbstractDao implements DaoInterface
         $class = $this->dtoClass();
         /** @var AbstractDto $dto */
         $dto = $class::fromArray($row);
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            $pk = $this->getPrimaryKey();
+            $idVal = $row[$pk] ?? null;
+            if ($idVal !== null) {
+                $uow->attach(static::class, (string)$idVal, $dto);
+            }
+        }
         return $dto;
     }
 
diff --git a/src/NoSql/Mongo/AbstractMongoDao.php b/src/NoSql/Mongo/AbstractMongoDao.php
index 111f559..0f48426 100644
--- a/src/NoSql/Mongo/AbstractMongoDao.php
+++ b/src/NoSql/Mongo/AbstractMongoDao.php
@@ -3,6 +3,7 @@
 namespace Pairity\NoSql\Mongo;
 
 use Pairity\Model\AbstractDto;
+use Pairity\Orm\UnitOfWork;
 
 /**
  * Base DAO for MongoDB collections returning DTOs.
@@ -131,32 +132,73 @@ abstract class AbstractMongoDao
 
     public function findById(string $id): ?AbstractDto
     {
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            $managed = $uow->get(static::class, (string)$id);
+            if ($managed instanceof AbstractDto) {
+                return $managed;
+            }
+        }
         return $this->findOneBy(['_id' => $id]);
     }
 
     /** @param array<string,mixed> $data */
     public function insert(array $data): AbstractDto
     {
-        $id = $this->connection->insertOne($this->databaseName(), $this->collection(), $data);
-        // fetch back
+        // Inserts remain immediate to obtain a real id, even under UoW
+        $id = UnitOfWork::suspendDuring(function () use ($data) {
+            return $this->connection->insertOne($this->databaseName(), $this->collection(), $data);
+        });
         return $this->findById($id) ?? $this->hydrate(array_merge($data, ['_id' => $id]));
     }
 
     /** @param array<string,mixed> $data */
     public function update(string $id, array $data): AbstractDto
     {
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            $self = $this; $conn = $this->connection; $theId = $id; $payload = $data;
+            $uow->enqueue($conn, function () use ($self, $theId, $payload) {
+                UnitOfWork::suspendDuring(function () use ($self, $theId, $payload) {
+                    $self->getConnection()->updateOne($self->databaseName(), $self->collection(), ['_id' => $theId], ['$set' => $payload]);
+                });
+            });
+            $base = $this->findById($id)?->toArray(false) ?? [];
+            $result = array_merge($base, $data, ['_id' => $id]);
+            return $this->hydrate($result);
+        }
         $this->connection->updateOne($this->databaseName(), $this->collection(), ['_id' => $id], ['$set' => $data]);
         return $this->findById($id) ?? $this->hydrate(array_merge($data, ['_id' => $id]));
     }
 
     public function deleteById(string $id): int
     {
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            $self = $this; $conn = $this->connection; $theId = $id;
+            $uow->enqueue($conn, function () use ($self, $theId) {
+                UnitOfWork::suspendDuring(function () use ($self, $theId) {
+                    $self->getConnection()->deleteOne($self->databaseName(), $self->collection(), ['_id' => $theId]);
+                });
+            });
+            return 0;
+        }
         return $this->connection->deleteOne($this->databaseName(), $this->collection(), ['_id' => $id]);
     }
 
     /** @param array<string,mixed>|Filter $filter */
     public function deleteBy(array|Filter $filter): int
     {
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            $self = $this; $conn = $this->connection; $flt = $this->normalizeFilterInput($filter);
+            $uow->enqueue($conn, function () use ($self, $flt) {
+                UnitOfWork::suspendDuring(function () use ($self, $flt) {
+                    $self->getConnection()->deleteOne($self->databaseName(), $self->collection(), $flt);
+                });
+            });
+            return 0;
+        }
         // For MVP provide deleteOne semantic; bulk deletes could be added later
         return $this->connection->deleteOne($this->databaseName(), $this->collection(), $this->normalizeFilterInput($filter));
     }
@@ -236,6 +278,13 @@ abstract class AbstractMongoDao
         $class = $this->dtoClass();
         /** @var AbstractDto $dto */
         $dto = $class::fromArray($doc);
+        $uow = UnitOfWork::current();
+        if ($uow && !UnitOfWork::isSuspended()) {
+            $idVal = $doc['_id'] ?? null;
+            if ($idVal !== null) {
+                $uow->attach(static::class, (string)$idVal, $dto);
+            }
+        }
         return $dto;
     }
 
diff --git a/src/Orm/UnitOfWork.php b/src/Orm/UnitOfWork.php
new file mode 100644
index 0000000..72570e4
--- /dev/null
+++ b/src/Orm/UnitOfWork.php
@@ -0,0 +1,153 @@
+<?php
+
+namespace Pairity\Orm;
+
+use Closure;
+
+/**
+ * Opt-in Unit of Work (MVP):
+ * - Ambient/current context with begin()/run()/current()
+ * - Identity Map per DAO class + primary key (string)
+ * - Deferred operation queues grouped by connection object
+ * - commit() opens transactions/sessions per connection and executes queued ops
+ */
+final class UnitOfWork
+{
+    /** @var UnitOfWork|null */
+    private static ?UnitOfWork $current = null;
+    /** @var bool */
+    private static bool $suspended = false; // when true, DAOs should execute immediately
+
+    /** @var array<string, array<string, object>> map[daoClass][id] = DTO */
+    private array $identityMap = [];
+
+    /**
+     * Queues grouped by a connection hash key.
+     * Each entry: ['conn' => object, 'ops' => list<Closure>]
+     *
+     * @var array<string, array{conn:object, ops:array<int,Closure>}> 
+     */
+    private array $queues = [];
+
+    private function __construct() {}
+
+    public static function begin(): UnitOfWork
+    {
+        if (self::$current !== null) {
+            return self::$current;
+        }
+        self::$current = new UnitOfWork();
+        return self::$current;
+    }
+
+    /**
+     * Run a Unit of Work and automatically commit or rollback on exception.
+     * @template T
+     * @param Closure(UnitOfWork):T $callback
+     * @return mixed
+     */
+    public static function run(Closure $callback): mixed
+    {
+        $uow = self::begin();
+        try {
+            $result = $callback($uow);
+            $uow->commit();
+            return $result;
+        } catch (\Throwable $e) {
+            $uow->rollback();
+            throw $e;
+        }
+    }
+
+    public static function current(): ?UnitOfWork
+    {
+        return self::$current;
+    }
+
+    /** Temporarily suspend UoW interception so DAOs execute immediately within the callable. */
+    public static function suspendDuring(Closure $cb): mixed
+    {
+        $prev = self::$suspended;
+        self::$suspended = true;
+        try { return $cb(); } finally { self::$suspended = $prev; }
+    }
+
+    public static function isSuspended(): bool
+    {
+        return self::$suspended;
+    }
+
+    // ===== Identity Map =====
+
+    /** Attach a DTO to identity map. */
+    public function attach(string $daoClass, string $id, object $dto): void
+    {
+        $this->identityMap[$daoClass][$id] = $dto;
+    }
+
+    /** Fetch an attached DTO if present. */
+    public function get(string $daoClass, string $id): ?object
+    {
+        return $this->identityMap[$daoClass][$id] ?? null;
+    }
+
+    // ===== Defer operations =====
+
+    /** Enqueue a mutation for the given connection object. */
+    public function enqueue(object $connection, Closure $operation): void
+    {
+        $key = spl_object_hash($connection);
+        if (!isset($this->queues[$key])) {
+            $this->queues[$key] = ['conn' => $connection, 'ops' => []];
+        }
+        $this->queues[$key]['ops'][] = $operation;
+    }
+
+    /** Execute all queued operations per connection within a transaction/session. */
+    public function commit(): void
+    {
+        // Ensure we run ops with DAO interception suspended to avoid re-enqueue
+        self::suspendDuring(function () {
+            // Grouped by connection type
+            foreach ($this->queues as $entry) {
+                $conn = $entry['conn'];
+                $ops = $entry['ops'];
+                // PDO/SQL path: has transaction(callable)
+                if (method_exists($conn, 'transaction')) {
+                    $conn->transaction(function () use ($ops) {
+                        foreach ($ops as $op) { $op(); }
+                        return null;
+                    });
+                }
+                // Mongo path: try withTransaction first, then withSession, else run directly
+                elseif (method_exists($conn, 'withTransaction')) {
+                    $conn->withTransaction(function () use ($ops) {
+                        foreach ($ops as $op) { $op(); }
+                        return null;
+                    });
+                } elseif (method_exists($conn, 'withSession')) {
+                    $conn->withSession(function () use ($ops) {
+                        foreach ($ops as $op) { $op(); }
+                        return null;
+                    });
+                } else {
+                    // Fallback: no transaction API; just run
+                    foreach ($ops as $op) { $op(); }
+                }
+            }
+        });
+
+        // Clear queues after successful commit
+        $this->queues = [];
+        // Do not clear identity map by default; keep for the scope
+        // Close UoW scope
+        self::$current = null;
+    }
+
+    /** Rollback just clears queues and current context; actual rollback is handled by transactions when run. */
+    public function rollback(): void
+    {
+        $this->queues = [];
+        self::$current = null;
+    }
+}
diff --git a/tests/UnitOfWorkSqliteTest.php b/tests/UnitOfWorkSqliteTest.php
new file mode 100644
index 0000000..36ed6a5
--- /dev/null
+++ b/tests/UnitOfWorkSqliteTest.php
@@ -0,0 +1,88 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Pairity\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Pairity\Database\ConnectionManager;
+use Pairity\Model\AbstractDto;
+use Pairity\Model\AbstractDao;
+use Pairity\Orm\UnitOfWork;
+
+final class UnitOfWorkSqliteTest extends TestCase
+{
+    private function conn()
+    {
+        return ConnectionManager::make(['driver' => 'sqlite', 'path' => ':memory:']);
+    }
+
+    public function testDeferredUpdateAndDeleteCommit(): void
+    {
+        $conn = $this->conn();
+        // schema
+        $conn->execute('CREATE TABLE users (id INTEGER PRIMARY KEY AUTOINCREMENT, email TEXT, name TEXT)');
+
+        // DAO/DTO inline
+        $dto = new class([]) extends AbstractDto {};
+        $dtoClass = get_class($dto);
+        $dao = new class($conn, $dtoClass) extends AbstractDao {
+            private string $dto;
+            public function __construct($c, string $dto) { parent::__construct($c); $this->dto = $dto; }
+            public function getTable(): string { return 'users'; }
+            protected function dtoClass(): string { return $this->dto; }
+            protected function schema(): array { return ['primaryKey' => 'id', 'columns' => ['id'=>['cast'=>'int'],'email'=>['cast'=>'string'],'name'=>['cast'=>'string']]]; }
+        };
+
+        // Insert immediate
+        $created = $dao->insert(['email' => 'u@example.com', 'name' => 'User']);
+        $id = (int)($created->toArray(false)['id'] ?? 0);
+        $this->assertGreaterThan(0, $id);
+
+        // Run UoW with deferred update and delete
+        UnitOfWork::run(function(UnitOfWork $uow) use ($dao, $id) {
+            $one = $dao->findById($id); // attaches to identity map
+            $this->assertNotNull($one);
+            // defer update
+            $dao->update($id, ['name' => 'Changed']);
+            // defer deleteBy criteria (will be executed after update)
+            $dao->deleteBy(['id' => $id]);
+            // commit done by run()
+        });
+
+        // After commit, record should be deleted
+        $this->assertNull($dao->findById($id));
+    }
+
+    public function testRollbackOnExceptionClearsOps(): void
+    {
+        $conn = $this->conn();
+        $conn->execute('CREATE TABLE users (id INTEGER PRIMARY KEY AUTOINCREMENT, email TEXT, name TEXT)');
+
+        $dto = new class([]) extends AbstractDto {};
+        $dtoClass = get_class($dto);
+        $dao = new class($conn, $dtoClass) extends AbstractDao {
+            private string $dto; public function __construct($c, string $dto) { parent::__construct($c); $this->dto = $dto; }
+            public function getTable(): string { return 'users'; }
+            protected function dtoClass(): string { return $this->dto; }
+            protected function schema(): array { return ['primaryKey'=>'id','columns'=>['id'=>['cast'=>'int'],'email'=>['cast'=>'string'],'name'=>['cast'=>'string']]]; }
+        };
+
+        $created = $dao->insert(['email' => 'x@example.com', 'name' => 'X']);
+        $id = (int)($created->toArray(false)['id'] ?? 0);
+
+        try {
+            UnitOfWork::run(function(UnitOfWork $uow) use ($dao, $id) {
+                $dao->update($id, ['name' => 'Won\'t Persist']);
+                throw new \RuntimeException('boom');
+            });
+            $this->fail('Exception expected');
+        } catch (\RuntimeException $e) {
+            // ok
+        }
+
+        // Update should not be applied due to rollback
+        $after = $dao->findById($id);
+        $this->assertSame('X', $after?->toArray(false)['name'] ?? null);
+    }
+}