diff --git a/libweave/external/crypto/p224.cc b/libweave/external/crypto/p224.cc
index b7c66c5..99fd2d1 100644
--- a/libweave/external/crypto/p224.cc
+++ b/libweave/external/crypto/p224.cc
@@ -11,16 +11,32 @@
 
 #include <string.h>
 
-#include <base/sys_byteorder.h>
-
 namespace weave {
 namespace crypto {
 namespace p224 {
 
 namespace {
 
-using base::HostToNet32;
-using base::NetToHost32;
+inline uint32 ByteSwap(uint32 x) {
+  return ((x & 0x000000fful) << 24) | ((x & 0x0000ff00ul) << 8) |
+         ((x & 0x00ff0000ul) >> 8) | ((x & 0xff000000ul) >> 24);
+}
+
+inline uint32 HostToNet32(uint32 x) {
+#if defined(ARCH_CPU_LITTLE_ENDIAN)
+  return ByteSwap(x);
+#else
+  return x;
+#endif
+}
+
+inline uint32 NetToHost32(uint32 x) {
+#if defined(ARCH_CPU_LITTLE_ENDIAN)
+  return ByteSwap(x);
+#else
+  return x;
+#endif
+}
 
 // Field element functions.
 //
@@ -655,7 +671,7 @@
 
 }  // anonymous namespace
 
-bool Point::SetFromString(const base::StringPiece& in) {
+bool Point::SetFromString(const std::string& in) {
   if (in.size() != 2*28)
     return false;
   const uint32* inwords = reinterpret_cast<const uint32*>(in.data());
diff --git a/libweave/external/crypto/p224.h b/libweave/external/crypto/p224.h
index a835ecd..ea15acf 100644
--- a/libweave/external/crypto/p224.h
+++ b/libweave/external/crypto/p224.h
@@ -8,7 +8,6 @@
 #include <string>
 
 #include <base/basictypes.h>
-#include <base/strings/string_piece.h>
 
 namespace weave {
 namespace crypto {
@@ -26,7 +25,7 @@
   // representation. The external point representation is an (x, y) pair of a
   // point on the curve. Each field element is represented as a big-endian
   // number < p.
-  bool SetFromString(const base::StringPiece& in);
+  bool SetFromString(const std::string& in);
 
   // ToString returns an external representation of the Point.
   std::string ToString() const;
diff --git a/libweave/external/crypto/p224_spake.cc b/libweave/external/crypto/p224_spake.cc
index 634c7e6..890002a 100644
--- a/libweave/external/crypto/p224_spake.cc
+++ b/libweave/external/crypto/p224_spake.cc
@@ -115,10 +115,9 @@
 
 }  // anonymous namespace
 
-P224EncryptedKeyExchange::P224EncryptedKeyExchange(
-    PeerType peer_type, const base::StringPiece& password)
-    : state_(kStateInitial),
-      is_server_(peer_type == kPeerTypeServer) {
+P224EncryptedKeyExchange::P224EncryptedKeyExchange(PeerType peer_type,
+                                                   const std::string& password)
+    : state_(kStateInitial), is_server_(peer_type == kPeerTypeServer) {
   memset(&x_, 0, sizeof(x_));
   memset(&expected_authenticator_, 0, sizeof(expected_authenticator_));
 
@@ -165,7 +164,7 @@
 }
 
 P224EncryptedKeyExchange::Result P224EncryptedKeyExchange::ProcessMessage(
-    const base::StringPiece& message) {
+    const std::string& message) {
   if (state_ == kStateRecvHash) {
     // This is the final state of the protocol: we are reading the peer's
     // authentication hash and checking that it matches the one that we expect.
@@ -212,11 +211,11 @@
 
   std::string client_masked_dh, server_masked_dh;
   if (is_server_) {
-    client_masked_dh = message.as_string();
+    client_masked_dh = message;
     server_masked_dh = next_message_;
   } else {
     client_masked_dh = next_message_;
-    server_masked_dh = message.as_string();
+    server_masked_dh = message;
   }
 
   // Now we calculate the hashes that each side will use to prove to the other
diff --git a/libweave/external/crypto/p224_spake.h b/libweave/external/crypto/p224_spake.h
index aea280d..547f8dc 100644
--- a/libweave/external/crypto/p224_spake.h
+++ b/libweave/external/crypto/p224_spake.h
@@ -8,7 +8,6 @@
 #include <string>
 
 #include <base/gtest_prod_util.h>
-#include <base/strings/string_piece.h>
 
 #include "libweave/external/crypto/p224.h"
 #include "libweave/external/crypto/sha2.h"
@@ -56,8 +55,7 @@
   // password: secret session password. Both parties to the
   //     authentication must pass the same value. For the case of a
   //     TLS connection, see RFC 5705.
-  P224EncryptedKeyExchange(PeerType peer_type,
-                           const base::StringPiece& password);
+  P224EncryptedKeyExchange(PeerType peer_type, const std::string& password);
 
   // GetNextMessage returns a byte string which must be passed to the other
   // party in the authentication.
@@ -65,7 +63,7 @@
 
   // ProcessMessage processes a message which must have been generated by a
   // call to GetNextMessage() by the other party.
-  Result ProcessMessage(const base::StringPiece& message);
+  Result ProcessMessage(const std::string& message);
 
   // In the event that ProcessMessage() returns kResultFailed, error will
   // return a human readable error message.
diff --git a/libweave/external/crypto/p224_unittest.cc b/libweave/external/crypto/p224_unittest.cc
index 5d149da..c0d3b2f 100644
--- a/libweave/external/crypto/p224_unittest.cc
+++ b/libweave/external/crypto/p224_unittest.cc
@@ -771,9 +771,9 @@
 TEST(P224, ExternalToInternalAndBack) {
   Point point;
 
-  EXPECT_TRUE(point.SetFromString(base::StringPiece(
-      reinterpret_cast<const char *>(kBasePointExternal),
-      sizeof(kBasePointExternal))));
+  EXPECT_TRUE(point.SetFromString(
+      std::string(reinterpret_cast<const char*>(kBasePointExternal),
+                  sizeof(kBasePointExternal))));
 
   const std::string external = point.ToString();
 
@@ -797,10 +797,10 @@
 TEST(P224, Addition) {
   Point a, b, minus_b, sum, a_again;
 
-  ASSERT_TRUE(a.SetFromString(base::StringPiece(
-      reinterpret_cast<const char *>(kNISTTestVectors[10].affine), 56)));
-  ASSERT_TRUE(b.SetFromString(base::StringPiece(
-      reinterpret_cast<const char *>(kNISTTestVectors[11].affine), 56)));
+  ASSERT_TRUE(a.SetFromString(std::string(
+      reinterpret_cast<const char*>(kNISTTestVectors[10].affine), 56)));
+  ASSERT_TRUE(b.SetFromString(std::string(
+      reinterpret_cast<const char*>(kNISTTestVectors[11].affine), 56)));
 
   p224::Negate(b, &minus_b);
   p224::Add(a, b, &sum);
diff --git a/libweave/external/crypto/sha2.cc b/libweave/external/crypto/sha2.cc
index 59a111d..d4e3ac9 100644
--- a/libweave/external/crypto/sha2.cc
+++ b/libweave/external/crypto/sha2.cc
@@ -12,14 +12,13 @@
 namespace weave {
 namespace crypto {
 
-void SHA256HashString(const base::StringPiece& str, uint8_t* output,
-                      size_t len) {
+void SHA256HashString(const std::string& str, uint8_t* output, size_t len) {
   std::string hash = SHA256HashString(str);
   len = std::min(hash.size(), len);
   std::copy(hash.begin(), hash.begin() + len, output);
 }
 
-std::string SHA256HashString(const base::StringPiece& str) {
+std::string SHA256HashString(const std::string& str) {
   SHA256_CTX sha_context;
   SHA256_Init(&sha_context);
   SHA256_Update(&sha_context, str.data(), str.size());
diff --git a/libweave/external/crypto/sha2.h b/libweave/external/crypto/sha2.h
index 34f6af8..920a798 100644
--- a/libweave/external/crypto/sha2.h
+++ b/libweave/external/crypto/sha2.h
@@ -7,8 +7,6 @@
 
 #include <string>
 
-#include <base/strings/string_piece.h>
-
 namespace weave {
 namespace crypto {
 
@@ -21,12 +19,11 @@
 // Computes the SHA-256 hash of the input string 'str' and stores the first
 // 'len' bytes of the hash in the output buffer 'output'.  If 'len' > 32,
 // only 32 bytes (the full hash) are stored in the 'output' buffer.
-void SHA256HashString(const base::StringPiece& str, uint8_t* output,
-                      size_t len);
+void SHA256HashString(const std::string& str, uint8_t* output, size_t len);
 
 // Convenience version of the above that returns the result in a 32-byte
 // string.
-std::string SHA256HashString(const base::StringPiece& str);
+std::string SHA256HashString(const std::string& str);
 
 }  // namespace crypto
 }  // namespace weave
diff --git a/libweave/include/weave/error.h b/libweave/include/weave/error.h
index 278d2f9..344f56f 100644
--- a/libweave/include/weave/error.h
+++ b/libweave/include/weave/error.h
@@ -9,7 +9,8 @@
 #include <string>
 
 #include <base/macros.h>
-#include <base/tracked_objects.h>
+#include <base/location.h>
+#include <base/compiler_specific.h>
 #include <weave/export.h>
 
 namespace weave {
diff --git a/libweave/include/weave/mock_task_runner.h b/libweave/include/weave/mock_task_runner.h
index 313e05f..d0d06f0 100644
--- a/libweave/include/weave/mock_task_runner.h
+++ b/libweave/include/weave/mock_task_runner.h
@@ -12,7 +12,7 @@
 #include <utility>
 #include <vector>
 
-#include <base/test/simple_test_clock.h>
+#include <base/time/clock.h>
 #include <gmock/gmock.h>
 
 namespace weave {
@@ -51,7 +51,7 @@
     }
   }
 
-  base::SimpleTestClock* GetClock() { return &test_clock_; }
+  base::Clock* GetClock() { return &test_clock_; }
 
  private:
   void SaveTask(const tracked_objects::Location& from_here,
@@ -69,7 +69,17 @@
   };
 
   size_t counter_{0};  // Keeps order of tasks with the same time.
-  base::SimpleTestClock test_clock_;
+
+  class TestClock : public base::Clock {
+   public:
+    base::Time Now() override { return now_; }
+
+    void SetNow(base::Time now) { now_ = now; }
+
+   private:
+    base::Time now_;
+  };
+  TestClock test_clock_;
 
   std::priority_queue<QueueItem,
                       std::vector<QueueItem>,
diff --git a/libweave/include/weave/task_runner.h b/libweave/include/weave/task_runner.h
index 0b349b6..66b83ab 100644
--- a/libweave/include/weave/task_runner.h
+++ b/libweave/include/weave/task_runner.h
@@ -10,6 +10,7 @@
 #include <vector>
 
 #include <base/callback.h>
+#include <base/location.h>
 
 namespace weave {
 
diff --git a/libweave/src/base_api_handler.cc b/libweave/src/base_api_handler.cc
index 3e641d7..b9e4de4 100644
--- a/libweave/src/base_api_handler.cc
+++ b/libweave/src/base_api_handler.cc
@@ -4,6 +4,8 @@
 
 #include "libweave/src/base_api_handler.h"
 
+#include <base/bind.h>
+
 #include "libweave/src/commands/command_instance.h"
 #include "libweave/src/commands/command_manager.h"
 #include "libweave/src/device_registration_info.h"
diff --git a/libweave/src/commands/command_queue.h b/libweave/src/commands/command_queue.h
index 851a283..66cc2d2 100644
--- a/libweave/src/commands/command_queue.h
+++ b/libweave/src/commands/command_queue.h
@@ -14,6 +14,7 @@
 
 #include <base/callback.h>
 #include <base/macros.h>
+#include <base/time/time.h>
 #include <weave/commands.h>
 
 #include "libweave/src/commands/command_instance.h"
diff --git a/libweave/src/commands/prop_constraints.cc b/libweave/src/commands/prop_constraints.cc
index c1ab1c4..babba85 100644
--- a/libweave/src/commands/prop_constraints.cc
+++ b/libweave/src/commands/prop_constraints.cc
@@ -5,6 +5,7 @@
 #include "libweave/src/commands/prop_constraints.h"
 
 #include <base/json/json_writer.h>
+#include <base/logging.h>
 
 #include "libweave/src/commands/prop_values.h"
 #include "libweave/src/commands/schema_constants.h"
diff --git a/libweave/src/commands/schema_utils.cc b/libweave/src/commands/schema_utils.cc
index 85455ed..b48b89b 100644
--- a/libweave/src/commands/schema_utils.cc
+++ b/libweave/src/commands/schema_utils.cc
@@ -9,6 +9,7 @@
 #include <string>
 
 #include <base/json/json_writer.h>
+#include <base/logging.h>
 
 #include "libweave/src/commands/object_schema.h"
 #include "libweave/src/commands/prop_types.h"
diff --git a/libweave/src/commands/schema_utils.h b/libweave/src/commands/schema_utils.h
index 5691ddd..570fb42 100644
--- a/libweave/src/commands/schema_utils.h
+++ b/libweave/src/commands/schema_utils.h
@@ -12,6 +12,7 @@
 #include <type_traits>
 #include <vector>
 
+#include <base/logging.h>
 #include <base/values.h>
 #include <weave/error.h>
 
diff --git a/libweave/src/commands/unittest_utils.cc b/libweave/src/commands/unittest_utils.cc
index 0b9c2e3..12a1c02 100644
--- a/libweave/src/commands/unittest_utils.cc
+++ b/libweave/src/commands/unittest_utils.cc
@@ -5,6 +5,7 @@
 #include "libweave/src/commands/unittest_utils.h"
 
 #include <base/json/json_reader.h>
+#include <base/logging.h>
 
 namespace weave {
 namespace unittests {
diff --git a/libweave/src/data_encoding_unittest.cc b/libweave/src/data_encoding_unittest.cc
index 76265cd..6a546f8 100644
--- a/libweave/src/data_encoding_unittest.cc
+++ b/libweave/src/data_encoding_unittest.cc
@@ -7,6 +7,7 @@
 #include <algorithm>
 #include <numeric>
 
+#include <base/logging.h>
 #include <gtest/gtest.h>
 
 namespace weave {
diff --git a/libweave/src/device_manager.cc b/libweave/src/device_manager.cc
index 0f51098..4187df7 100644
--- a/libweave/src/device_manager.cc
+++ b/libweave/src/device_manager.cc
@@ -6,6 +6,8 @@
 
 #include <string>
 
+#include <base/bind.h>
+
 #include "libweave/src/base_api_handler.h"
 #include "libweave/src/commands/command_manager.h"
 #include "libweave/src/config.h"
diff --git a/libweave/src/device_registration_info.h b/libweave/src/device_registration_info.h
index 45f2257..564fb87 100644
--- a/libweave/src/device_registration_info.h
+++ b/libweave/src/device_registration_info.h
@@ -13,11 +13,8 @@
 
 #include <base/callback.h>
 #include <base/macros.h>
-#include <base/memory/ref_counted.h>
 #include <base/memory/weak_ptr.h>
-#include <base/single_thread_task_runner.h>
 #include <base/time/time.h>
-#include <base/timer/timer.h>
 #include <weave/error.h>
 #include <weave/cloud.h>
 #include <weave/http_client.h>
diff --git a/libweave/src/notification/pull_channel.h b/libweave/src/notification/pull_channel.h
index 7b10152..7f1b789 100644
--- a/libweave/src/notification/pull_channel.h
+++ b/libweave/src/notification/pull_channel.h
@@ -10,6 +10,7 @@
 
 #include <base/macros.h>
 #include <base/memory/weak_ptr.h>
+#include <base/time/time.h>
 
 #include "libweave/src/notification/notification_channel.h"
 
diff --git a/libweave/src/notification/xmpp_channel_unittest.cc b/libweave/src/notification/xmpp_channel_unittest.cc
index 1816288..eaacf83 100644
--- a/libweave/src/notification/xmpp_channel_unittest.cc
+++ b/libweave/src/notification/xmpp_channel_unittest.cc
@@ -7,7 +7,6 @@
 #include <algorithm>
 #include <queue>
 
-#include <base/test/simple_test_clock.h>
 #include <gtest/gtest.h>
 #include <weave/mock_task_runner.h>
 
diff --git a/libweave/src/notification/xmpp_iq_stanza_handler.h b/libweave/src/notification/xmpp_iq_stanza_handler.h
index eb1f1b6..b4edcac 100644
--- a/libweave/src/notification/xmpp_iq_stanza_handler.h
+++ b/libweave/src/notification/xmpp_iq_stanza_handler.h
@@ -11,8 +11,8 @@
 
 #include <base/callback_forward.h>
 #include <base/macros.h>
+#include <base/time/time.h>
 #include <base/memory/weak_ptr.h>
-#include <base/single_thread_task_runner.h>
 
 #include "libweave/src/notification/xmpp_stream_parser.h"
 
diff --git a/libweave/src/privet/privet_handler.cc b/libweave/src/privet/privet_handler.cc
index b83df36..97a8d6a 100644
--- a/libweave/src/privet/privet_handler.cc
+++ b/libweave/src/privet/privet_handler.cc
@@ -11,7 +11,6 @@
 
 #include <base/bind.h>
 #include <base/location.h>
-#include <base/stl_util.h>
 #include <base/strings/string_number_conversions.h>
 #include <base/strings/stringprintf.h>
 #include <base/values.h>
@@ -533,7 +532,8 @@
 
   PairingType pairing;
   std::set<PairingType> modes = security_->GetPairingTypes();
-  if (!StringToEnum(pairing_str, &pairing) || !ContainsKey(modes, pairing)) {
+  if (!StringToEnum(pairing_str, &pairing) ||
+      modes.find(pairing) == modes.end()) {
     Error::AddToPrintf(&error, FROM_HERE, errors::kDomain,
                        errors::kInvalidParams, kInvalidParamValueFormat,
                        kPairingKey, pairing_str.c_str());
@@ -542,7 +542,8 @@
 
   CryptoType crypto;
   std::set<CryptoType> cryptos = security_->GetCryptoTypes();
-  if (!StringToEnum(crypto_str, &crypto) || !ContainsKey(cryptos, crypto)) {
+  if (!StringToEnum(crypto_str, &crypto) ||
+      cryptos.find(crypto) == cryptos.end()) {
     Error::AddToPrintf(&error, FROM_HERE, errors::kDomain,
                        errors::kInvalidParams, kInvalidParamValueFormat,
                        kCryptoKey, crypto_str.c_str());
diff --git a/libweave/src/privet/privet_types.h b/libweave/src/privet/privet_types.h
index b46e5b6..d013500 100644
--- a/libweave/src/privet/privet_types.h
+++ b/libweave/src/privet/privet_types.h
@@ -7,6 +7,7 @@
 
 #include <string>
 
+#include <base/logging.h>
 #include <weave/error.h>
 
 namespace weave {
diff --git a/libweave/src/privet/security_manager.cc b/libweave/src/privet/security_manager.cc
index 409f09a..588cbd3 100644
--- a/libweave/src/privet/security_manager.cc
+++ b/libweave/src/privet/security_manager.cc
@@ -13,7 +13,6 @@
 #include <base/guid.h>
 #include <base/logging.h>
 #include <base/rand_util.h>
-#include <base/stl_util.h>
 #include <base/strings/string_number_conversions.h>
 #include <base/strings/stringprintf.h>
 #include <base/time/time.h>
diff --git a/libweave/src/privet/security_manager.h b/libweave/src/privet/security_manager.h
index 60c59e8..07f8c0c 100644
--- a/libweave/src/privet/security_manager.h
+++ b/libweave/src/privet/security_manager.h
@@ -12,6 +12,7 @@
 #include <vector>
 
 #include <base/callback.h>
+#include <base/gtest_prod_util.h>
 #include <base/memory/weak_ptr.h>
 #include <weave/error.h>
 
diff --git a/libweave/src/states/state_change_queue.cc b/libweave/src/states/state_change_queue.cc
index 345e532..8f787ca 100644
--- a/libweave/src/states/state_change_queue.cc
+++ b/libweave/src/states/state_change_queue.cc
@@ -15,8 +15,6 @@
 
 bool StateChangeQueue::NotifyPropertiesUpdated(base::Time timestamp,
                                                ValueMap changed_properties) {
-  DCHECK(thread_checker_.CalledOnValidThread());
-
   auto& stored_changes = state_changes_[timestamp];
   // Merge the old property set.
   changed_properties.insert(stored_changes.begin(), stored_changes.end());
@@ -41,7 +39,6 @@
 }
 
 std::vector<StateChange> StateChangeQueue::GetAndClearRecordedStateChanges() {
-  DCHECK(thread_checker_.CalledOnValidThread());
   std::vector<StateChange> changes;
   changes.reserve(state_changes_.size());
   for (const auto& pair : state_changes_) {
diff --git a/libweave/src/states/state_change_queue.h b/libweave/src/states/state_change_queue.h
index 4b2acaf..3289209 100644
--- a/libweave/src/states/state_change_queue.h
+++ b/libweave/src/states/state_change_queue.h
@@ -30,11 +30,6 @@
   void NotifyStateUpdatedOnServer(UpdateID update_id) override;
 
  private:
-  // To make sure we do not call NotifyPropertiesUpdated() and
-  // GetAndClearRecordedStateChanges() on different threads, |thread_checker_|
-  // is here to help us with verifying the single-threaded operation.
-  base::ThreadChecker thread_checker_;
-
   // Maximum queue size. If it is full, the oldest state update records are
   // merged together until the queue size is within the size limit.
   const size_t max_queue_size_;
diff --git a/libweave/src/weave_testrunner.cc b/libweave/src/weave_testrunner.cc
index 215818f..5de7cae 100644
--- a/libweave/src/weave_testrunner.cc
+++ b/libweave/src/weave_testrunner.cc
@@ -2,13 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include <base/at_exit.h>
 #include <base/command_line.h>
+#include <base/logging.h>
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
 int main(int argc, char** argv) {
-  base::AtExitManager exit_manager;
   base::CommandLine::Init(argc, argv);
 
   logging::LoggingSettings settings;