diff --git a/src/Bid/Bid.php b/src/Bid/Bid.php
new file mode 100644
index 0000000..3cc7018
--- /dev/null
+++ b/src/Bid/Bid.php
@@ -0,0 +1,32 @@
+<?php
+
+namespace FreightQuote\Bid;
+
+class Bid
+{
+    public function __construct(
+        private ?string $id,
+        private int $freightOrderId,
+        private int $carrierId,
+    ) {}
+
+    public function getId(): ?string
+    {
+        return $this->id;
+    }
+
+    public function setId(string $id): void
+    {
+        $this->id = $id;
+    }
+
+    public function getFreightOrderId(): int
+    {
+        return $this->freightOrderId;
+    }
+
+    public function getCarrierId(): int
+    {
+        return $this->carrierId;
+    }
+}
diff --git a/src/Bid/BidRepository.php b/src/Bid/BidRepository.php
new file mode 100644
index 0000000..d9d49f5
--- /dev/null
+++ b/src/Bid/BidRepository.php
@@ -0,0 +1,8 @@
+<?php
+
+namespace FreightQuote\Bid;
+
+interface BidRepository
+{
+    public function save(Bid $bid): Bid;
+}
diff --git a/tests/Fakes/Bid/FakeBidRepository.php b/tests/Fakes/Bid/FakeBidRepository.php
new file mode 100644
index 0000000..61478d9
--- /dev/null
+++ b/tests/Fakes/Bid/FakeBidRepository.php
@@ -0,0 +1,54 @@
+<?php
+
+namespace Tests\Fakes\Bid;
+
+use FreightQuote\Bid\Bid;
+use FreightQuote\Bid\BidRepository;
+
+class FakeBidRepository implements BidRepository
+{
+    /**
+     * @var Bid[]
+     */
+    private array $existingBids = [];
+
+    public function save(Bid $bid): Bid
+    {
+        $id = $bid->getId();
+        if ($id === null) {
+            $id = $this->getUniqueId();
+            $bid->setId($id);
+        }
+        $this->existingBids[$id] = $bid;
+
+        return new Bid(
+            $id,
+            $bid->getFreightOrderId(),
+            $bid->getCarrierId(),
+        );
+    }
+
+    public function find(string $id): ?Bid
+    {
+        foreach ($this->existingBids as $bid) {
+            if ($bid->getId() === $id) {
+                return new Bid(
+                    $id,
+                    $bid->getFreightOrderId(),
+                    $bid->getCarrierId(),
+                );
+            }
+        }
+
+        return null;
+    }
+
+    private function getUniqueId(): string
+    {
+        $id = uniqid('', true);
+        while ($this->find($id) !== null) {
+            $id = uniqid('', true);
+        }
+        return $id;
+    }
+}