diff --git a/fastpair/handshake/BUILD b/fastpair/handshake/BUILD
index 526c8873..2b6b079e 100644
--- a/fastpair/handshake/BUILD
+++ b/fastpair/handshake/BUILD
@@ -43,7 +43,6 @@ cc_library(
         "//fastpair/repository",
         "//fastpair/server_access",
         "//internal/base:bluetooth_address",
-        "//internal/platform:base",
         "//internal/platform:comm",
         "//internal/platform:logging",
         "//internal/platform:types",
@@ -54,6 +53,8 @@ cc_library(
         "@com_google_absl//absl/functional:bind_front",
         "@com_google_absl//absl/strings",
         "@com_google_absl//absl/synchronization",
+        "@com_google_absl//absl/time",
+        "@com_google_absl//absl/types:span",
     ],
 )
 
@@ -120,6 +121,7 @@ cc_test(
         "//internal/platform/implementation/g3",  # build_cleaner: keep
         "//internal/test",
         "@com_github_protobuf_matchers//protobuf-matchers",
+        "@com_google_absl//absl/status",
         "@com_google_absl//absl/strings",
         "@com_google_absl//absl/time",
         "@com_google_googletest//:gtest_main",
diff --git a/fastpair/handshake/fake_fast_pair_gatt_service_client.h b/fastpair/handshake/fake_fast_pair_gatt_service_client.h
index 2274034e..019e2e0d 100644
--- a/fastpair/handshake/fake_fast_pair_gatt_service_client.h
+++ b/fastpair/handshake/fake_fast_pair_gatt_service_client.h
@@ -43,26 +43,28 @@ class FakeFastPairGattServiceClient : public FastPairGattServiceClient {
       WriteResponseCallback write_response_callback) override {
     key_based_write_response_callback_ = std::move(write_response_callback);
   }
+
   void WritePasskeyAsync(
       uint8_t message_type, uint32_t passkey,
       const FastPairDataEncryptor& fast_pair_data_encryptor,
       WriteResponseCallback write_response_callback) override {
     passkey_write_response_callback_ = std::move(write_response_callback);
   }
+
   void RunOnGattClientInitializedCallback(
-      std::optional<PairFailure> failure = absl::nullopt) {
+      std::optional<PairFailure> failure = std::nullopt) {
     std::move(on_initialized_callback_)(failure);
   }
 
   void RunWriteResponseCallback(
       absl::string_view value,
-      std::optional<PairFailure> failure = absl::nullopt) {
+      std::optional<PairFailure> failure = std::nullopt) {
     std::move(key_based_write_response_callback_)(value, failure);
   }
 
   void RunWritePasskeyCallback(
       absl::string_view value,
-      std::optional<PairFailure> failure = absl::nullopt) {
+      std::optional<PairFailure> failure = std::nullopt) {
     std::move(passkey_write_response_callback_)(value, failure);
   }
 
diff --git a/fastpair/handshake/fast_pair_gatt_service_client_impl.cc b/fastpair/handshake/fast_pair_gatt_service_client_impl.cc
index bb0685f5..4c0e2d04 100644
--- a/fastpair/handshake/fast_pair_gatt_service_client_impl.cc
+++ b/fastpair/handshake/fast_pair_gatt_service_client_impl.cc
@@ -16,6 +16,7 @@
 
 #include <algorithm>
 #include <array>
+#include <cstdint>
 #include <iterator>
 #include <memory>
 #include <optional>
@@ -27,7 +28,11 @@
 #include "absl/functional/any_invocable.h"
 #include "absl/functional/bind_front.h"
 #include "absl/strings/string_view.h"
+#include "absl/time/time.h"
+#include "absl/types/span.h"
 #include "fastpair/common/constant.h"
+#include "fastpair/common/fast_pair_device.h"
+#include "fastpair/common/pair_failure.h"
 #include "fastpair/handshake/fast_pair_data_encryptor.h"
 #include "fastpair/handshake/fast_pair_gatt_service_client.h"
 #include "internal/base/bluetooth_address.h"
@@ -168,7 +173,7 @@ void FastPairGattServiceClientImpl::GetFastPairGattCharacteristics() {
   }
 
   is_initialized_ = true;
-  std::move(on_gatt_initialized_callback_)(absl::nullopt);
+  std::move(on_gatt_initialized_callback_)(std::nullopt);
 }
 
 std::optional<GattCharacteristic>
@@ -340,7 +345,7 @@ void FastPairGattServiceClientImpl::WritePasskeyAsync(
   // Subscribe the notification once the passkey characteristic's value changed
   if (SubscribePasskeyCharacteristic()) {
     is_passkey_notification_subscribed_ = true;
-    // Write passkey confonirmation request to the passkey characteristic
+    // Write passkey confirmation request to the passkey characteristic
     WritePasskeyCharacteristic(
         std::string(data_to_write_vec.begin(), data_to_write_vec.end()));
   }
diff --git a/fastpair/handshake/fast_pair_gatt_service_client_impl_test.cc b/fastpair/handshake/fast_pair_gatt_service_client_impl_test.cc
index 07f36962..f6750688 100644
--- a/fastpair/handshake/fast_pair_gatt_service_client_impl_test.cc
+++ b/fastpair/handshake/fast_pair_gatt_service_client_impl_test.cc
@@ -15,17 +15,21 @@
 #include "fastpair/handshake/fast_pair_gatt_service_client_impl.h"
 
 #include <array>
+#include <cstdint>
 #include <memory>
 #include <optional>
 #include <string>
 
 #include "gtest/gtest.h"
+#include "absl/status/status.h"
 #include "absl/strings/string_view.h"
 #include "absl/time/time.h"
 #include "fastpair/common/constant.h"
 #include "fastpair/common/fast_pair_device.h"
 #include "fastpair/common/pair_failure.h"
+#include "fastpair/common/protocol.h"
 #include "fastpair/handshake/fake_fast_pair_data_encryptor.h"
+#include "fastpair/handshake/fast_pair_gatt_service_client.h"
 #include "internal/platform/ble_v2.h"
 #include "internal/platform/bluetooth_adapter.h"
 #include "internal/platform/byte_array.h"
@@ -188,18 +192,16 @@ class FastPairGattServiceClientTest : public testing::Test {
         passkey_characteristic_.value(), false, {});
   }
 
-  absl::optional<PairFailure> GetInitializedCallbackResult() {
+  std::optional<PairFailure> GetInitializedCallbackResult() {
     return initalized_failure_;
   }
 
   void WriteTestCallback(absl::string_view response,
-                         absl::optional<PairFailure> failure) {
+                         std::optional<PairFailure> failure) {
     write_failure_ = failure;
   }
 
-  absl::optional<PairFailure> GetWriteCallbackResult() {
-    return write_failure_;
-  }
+  std::optional<PairFailure> GetWriteCallbackResult() { return write_failure_; }
 
   void WriteRequestToKeyBased() {
     gatt_client_->WriteRequestAsync(
@@ -240,8 +242,8 @@ class FastPairGattServiceClientTest : public testing::Test {
  private:
   std::optional<GattCharacteristic> key_based_characteristic_;
   std::optional<GattCharacteristic> passkey_characteristic_;
-  absl::optional<PairFailure> initalized_failure_;
-  absl::optional<PairFailure> write_failure_;
+  std::optional<PairFailure> initalized_failure_;
+  std::optional<PairFailure> write_failure_;
   Property properties_ = Property::kWrite | Property::kNotify;
   Permission permissions_ = Permission::kWrite;
 };
@@ -277,7 +279,7 @@ TEST_F(FastPairGattServiceClientTest, SuccessfulWriteKeyBaseCharacteristics) {
   InitializeFastPairGattServiceClient();
   WriteRequestToKeyBased();
   EXPECT_EQ(TriggerKeyBasedGattChanged(), absl::OkStatus());
-  EXPECT_EQ(GetWriteCallbackResult(), absl::nullopt);
+  EXPECT_EQ(GetWriteCallbackResult(), std::nullopt);
 }
 
 TEST_F(FastPairGattServiceClientTest, SuccessfulWritePasskeyCharacteristics) {
@@ -285,7 +287,7 @@ TEST_F(FastPairGattServiceClientTest, SuccessfulWritePasskeyCharacteristics) {
   InitializeFastPairGattServiceClient();
   WriteRequestToPasskey();
   EXPECT_EQ(TriggerPasskeyGattChanged(), absl::OkStatus());
-  EXPECT_EQ(GetWriteCallbackResult(), absl::nullopt);
+  EXPECT_EQ(GetWriteCallbackResult(), std::nullopt);
 }
 
 TEST_F(FastPairGattServiceClientTest, FailedSubscribeKeybaseCharacteristic) {
@@ -297,7 +299,7 @@ TEST_F(FastPairGattServiceClientTest, FailedSubscribeKeybaseCharacteristic) {
             PairFailure::kKeyBasedPairingCharacteristicSubscription);
   WriteRequestToPasskey();
   EXPECT_EQ(TriggerPasskeyGattChanged(), absl::OkStatus());
-  EXPECT_EQ(GetWriteCallbackResult(), absl::nullopt);
+  EXPECT_EQ(GetWriteCallbackResult(), std::nullopt);
 }
 
 TEST_F(FastPairGattServiceClientTest, FailedSubscribePasskeyCharacteristic) {
@@ -306,7 +308,7 @@ TEST_F(FastPairGattServiceClientTest, FailedSubscribePasskeyCharacteristic) {
   RemoveDiscoveredPasskeyCharacteristic();
   WriteRequestToKeyBased();
   EXPECT_EQ(TriggerKeyBasedGattChanged(), absl::OkStatus());
-  EXPECT_EQ(GetWriteCallbackResult(), absl::nullopt);
+  EXPECT_EQ(GetWriteCallbackResult(), std::nullopt);
   WriteRequestToPasskey();
   EXPECT_EQ(GetWriteCallbackResult(),
             PairFailure::kPasskeyCharacteristicSubscription);
diff --git a/fastpair/handshake/fast_pair_handshake_lookup.cc b/fastpair/handshake/fast_pair_handshake_lookup.cc
index cad7e193..a137280d 100644
--- a/fastpair/handshake/fast_pair_handshake_lookup.cc
+++ b/fastpair/handshake/fast_pair_handshake_lookup.cc
@@ -20,6 +20,7 @@
 #include "absl/strings/string_view.h"
 #include "absl/synchronization/mutex.h"
 #include "fastpair/handshake/fast_pair_handshake_impl.h"
+#include "internal/platform/logging.h"
 
 namespace nearby {
 namespace fastpair {