diff --git a/y2020/control_loops/drivetrain/drivetrain_base.cc b/y2020/control_loops/drivetrain/drivetrain_base.cc
index 7b42df5..3e05020 100644
--- a/y2020/control_loops/drivetrain/drivetrain_base.cc
+++ b/y2020/control_loops/drivetrain/drivetrain_base.cc
@@ -15,9 +15,7 @@
 
 namespace chrono = ::std::chrono;
 
-namespace y2020 {
-namespace control_loops {
-namespace drivetrain {
+namespace y2020::control_loops::drivetrain {
 
 using ::frc971::constants::ShifterHallEffect;
 
@@ -77,6 +75,4 @@
   return kDrivetrainConfig;
 };
 
-}  // namespace drivetrain
-}  // namespace control_loops
-}  // namespace y2020
+}  // namespace y2020::control_loops::drivetrain
diff --git a/y2020/control_loops/drivetrain/drivetrain_replay_test.cc b/y2020/control_loops/drivetrain/drivetrain_replay_test.cc
index 0baf34b..731f02c 100644
--- a/y2020/control_loops/drivetrain/drivetrain_replay_test.cc
+++ b/y2020/control_loops/drivetrain/drivetrain_replay_test.cc
@@ -27,10 +27,7 @@
 DEFINE_string(config, "y2020/aos_config.json",
               "Name of the config file to replay using.");
 
-namespace y2020 {
-namespace control_loops {
-namespace drivetrain {
-namespace testing {
+namespace y2020::control_loops::drivetrain::testing {
 
 class DrivetrainReplayTest : public ::testing::Test {
  public:
@@ -135,7 +132,4 @@
   EXPECT_LT(std::abs(status_fetcher_->theta()), 0.02);
 }
 
-}  // namespace testing
-}  // namespace drivetrain
-}  // namespace control_loops
-}  // namespace y2020
+}  // namespace y2020::control_loops::drivetrain::testing
diff --git a/y2020/control_loops/drivetrain/localizer.cc b/y2020/control_loops/drivetrain/localizer.cc
index 8f8bf87..fabbb8e 100644
--- a/y2020/control_loops/drivetrain/localizer.cc
+++ b/y2020/control_loops/drivetrain/localizer.cc
@@ -6,9 +6,7 @@
             "If true, send LocalizerDebug messages on every tick, even if "
             "they would be empty.");
 
-namespace y2020 {
-namespace control_loops {
-namespace drivetrain {
+namespace y2020::control_loops::drivetrain {
 
 namespace {
 // Converts a flatbuffer TransformationMatrix to an Eigen matrix. Technically,
@@ -499,6 +497,4 @@
   return Zhat;
 }
 
-}  // namespace drivetrain
-}  // namespace control_loops
-}  // namespace y2020
+}  // namespace y2020::control_loops::drivetrain
diff --git a/y2020/control_loops/drivetrain/localizer_test.cc b/y2020/control_loops/drivetrain/localizer_test.cc
index 3e2cf6b..90076c0 100644
--- a/y2020/control_loops/drivetrain/localizer_test.cc
+++ b/y2020/control_loops/drivetrain/localizer_test.cc
@@ -19,10 +19,7 @@
 
 // This file tests that the full 2020 localizer behaves sanely.
 
-namespace y2020 {
-namespace control_loops {
-namespace drivetrain {
-namespace testing {
+namespace y2020::control_loops::drivetrain::testing {
 
 using aos::logger::BootTimestamp;
 using frc971::control_loops::drivetrain::DrivetrainConfig;
@@ -622,7 +619,4 @@
   RunFor(chrono::seconds(20));
 }
 
-}  // namespace testing
-}  // namespace drivetrain
-}  // namespace control_loops
-}  // namespace y2020
+}  // namespace y2020::control_loops::drivetrain::testing