diff --git a/checker/standard_library.cc b/checker/standard_library.cc
index 67683edc8..5cb10a116 100644
--- a/checker/standard_library.cc
+++ b/checker/standard_library.cc
@@ -103,18 +103,6 @@ Type TypeBytesType() {
   return *kInstance;
 }
 
-Type TypeDurationType() {
-  static absl::NoDestructor<Type> kInstance(
-      TypeType(BuiltinsArena(), DurationType()));
-  return *kInstance;
-}
-
-Type TypeTimestampType() {
-  static absl::NoDestructor<Type> kInstance(
-      TypeType(BuiltinsArena(), TimestampType()));
-  return *kInstance;
-}
-
 Type TypeDynType() {
   static absl::NoDestructor<Type> kInstance(
       TypeType(BuiltinsArena(), DynType()));
diff --git a/common/values/custom_list_value_test.cc b/common/values/custom_list_value_test.cc
index d05939164..00d35fdbb 100644
--- a/common/values/custom_list_value_test.cc
+++ b/common/values/custom_list_value_test.cc
@@ -54,7 +54,7 @@ using ::testing::Optional;
 using ::testing::Pair;
 using ::testing::UnorderedElementsAre;
 
-struct CustomListValueTest;
+class CustomListValueTest;
 
 struct CustomListValueTestContent {
   google::protobuf::Arena* absl_nonnull arena;
diff --git a/common/values/custom_map_value_test.cc b/common/values/custom_map_value_test.cc
index a38ffe537..8c3183cf8 100644
--- a/common/values/custom_map_value_test.cc
+++ b/common/values/custom_map_value_test.cc
@@ -56,7 +56,7 @@ using ::testing::Optional;
 using ::testing::Pair;
 using ::testing::UnorderedElementsAre;
 
-struct CustomMapValueTest;
+class CustomMapValueTest;
 
 struct CustomMapValueTestContent {
   google::protobuf::Arena* absl_nonnull arena;
diff --git a/common/values/custom_struct_value_test.cc b/common/values/custom_struct_value_test.cc
index 8e31a3389..0f5ac39c5 100644
--- a/common/values/custom_struct_value_test.cc
+++ b/common/values/custom_struct_value_test.cc
@@ -55,7 +55,7 @@ using ::testing::NotNull;
 using ::testing::Pair;
 using ::testing::UnorderedElementsAre;
 
-struct CustomStructValueTest;
+class CustomStructValueTest;
 
 struct CustomStructValueTestContent {
   google::protobuf::Arena* absl_nonnull arena;
diff --git a/eval/eval/logic_step_test.cc b/eval/eval/logic_step_test.cc
index 6367f01ef..98aca0df3 100644
--- a/eval/eval/logic_step_test.cc
+++ b/eval/eval/logic_step_test.cc
@@ -104,7 +104,7 @@ class LogicStepTest : public testing::TestWithParam<bool> {
   }
 
  private:
-  absl_nonnull std::shared_ptr<class RuntimeEnv> env_;
+  absl_nonnull std::shared_ptr<const RuntimeEnv> env_;
   Arena arena_;
 };
 
diff --git a/internal/number_test.cc b/internal/number_test.cc
index 69aacb4fd..3cdcf2b2d 100644
--- a/internal/number_test.cc
+++ b/internal/number_test.cc
@@ -22,9 +22,6 @@
 namespace cel::internal {
 namespace {
 
-constexpr double kNan = std::numeric_limits<double>::quiet_NaN();
-constexpr double kInfinity = std::numeric_limits<double>::infinity();
-
 TEST(Number, Basic) {
   EXPECT_GT(Number(1.1), Number::FromInt64(1));
   EXPECT_LT(Number::FromUint64(1), Number(1.1));