diff --git a/core/common/src/main/scala/org/typelevel/otel4s/KindTransformer.scala b/core/common/src/main/scala/org/typelevel/otel4s/KindTransformer.scala
index e6c553e4b..889dd0992 100644
--- a/core/common/src/main/scala/org/typelevel/otel4s/KindTransformer.scala
+++ b/core/common/src/main/scala/org/typelevel/otel4s/KindTransformer.scala
@@ -18,6 +18,7 @@ package org.typelevel.otel4s
 
 import cats.Functor
 import cats.Monad
+import cats.arrow.FunctionK
 import cats.data.EitherT
 import cats.data.IorT
 import cats.data.Kleisli
@@ -54,14 +55,25 @@ trait KindTransformer[F[_], G[_]] {
 
   /** Lifts a natural transformation from `F` to `F` into a natural
     * transformation from `G` to `G`.
+    *
+    * @note
+    *   Implementors SHOULD NOT override this method; the only reason it is not
+    *   final is for optimization of the identity case.
     */
-  final def liftFunctionK(f: F ~> F): G ~> G =
+  def liftFunctionK(f: F ~> F): G ~> G =
     new (G ~> G) {
       def apply[A](ga: G[A]): G[A] = limitedMapK(ga)(f)
     }
 }
 
 object KindTransformer {
+  implicit def id[F[_]]: KindTransformer[F, F] =
+    new KindTransformer[F, F] {
+      val liftK: F ~> F = FunctionK.id
+      def limitedMapK[A](ga: F[A])(f: F ~> F): F[A] = f(ga)
+      override def liftFunctionK(f: F ~> F): F ~> F = f
+    }
+
   implicit def optionT[F[_]: Functor]: KindTransformer[F, OptionT[F, *]] =
     new KindTransformer[F, OptionT[F, *]] {
       val liftK: F ~> OptionT[F, *] = OptionT.liftK
diff --git a/java/trace/src/test/scala/org/typelevel/otel4s/java/trace/TracerSuite.scala b/java/trace/src/test/scala/org/typelevel/otel4s/java/trace/TracerSuite.scala
index b08122320..5cd39afbc 100644
--- a/java/trace/src/test/scala/org/typelevel/otel4s/java/trace/TracerSuite.scala
+++ b/java/trace/src/test/scala/org/typelevel/otel4s/java/trace/TracerSuite.scala
@@ -938,7 +938,33 @@ class TracerSuite extends CatsEffectSuite {
     }
   }
 
-  test("nested SpanOps#surround for Tracer[OptionT[IO, *]]") {
+  test("nested SpanOps#surround for Tracer[IO].mapK[IO]") {
+    TestControl.executeEmbed {
+      for {
+        now <- IO.monotonic.delayBy(1.second) // otherwise returns 0
+        sdk <- makeSdk()
+        tracerIO <- sdk.provider.get("tracer")
+        tracer = tracerIO.mapK[IO]
+        _ <- tracer
+          .span("outer")
+          .surround {
+            for {
+              _ <- IO.sleep(NestedSurround.preBodyDuration)
+              _ <- tracer
+                .span("body-1")
+                .surround(IO.sleep(NestedSurround.body1Duration))
+              _ <- tracer
+                .span("body-2")
+                .surround(IO.sleep(NestedSurround.body2Duration))
+            } yield ()
+          }
+        spans <- sdk.finishedSpans
+        tree <- IO.pure(SpanNode.fromSpans(spans))
+      } yield assertEquals(tree, List(NestedSurround.expected(now)))
+    }
+  }
+
+  test("nested SpanOps#surround for Tracer[IO].mapK[OptionT[IO, *]]") {
     TestControl.executeEmbed {
       for {
         now <- IO.monotonic.delayBy(1.second) // otherwise returns 0
@@ -965,7 +991,7 @@ class TracerSuite extends CatsEffectSuite {
     }
   }
 
-  test("nested SpanOps#surround for Tracer[EitherT[IO, String, *]]") {
+  test("nested SpanOps#surround for Tracer[IO].mapK[EitherT[IO, String, *]]") {
     TestControl.executeEmbed {
       for {
         now <- IO.monotonic.delayBy(1.second) // otherwise returns 0
@@ -992,7 +1018,7 @@ class TracerSuite extends CatsEffectSuite {
     }
   }
 
-  test("nested SpanOps#surround for Tracer[IorT[IO, String, *]]") {
+  test("nested SpanOps#surround for Tracer[IO].mapK[IorT[IO, String, *]]") {
     TestControl.executeEmbed {
       for {
         now <- IO.monotonic.delayBy(1.second) // otherwise returns 0
@@ -1019,7 +1045,7 @@ class TracerSuite extends CatsEffectSuite {
     }
   }
 
-  test("nested SpanOps#surround for Tracer[Kleisli[IO, String, *]]") {
+  test("nested SpanOps#surround for Tracer[IO].mapK[Kleisli[IO, String, *]]") {
     TestControl.executeEmbed {
       for {
         now <- IO.monotonic.delayBy(1.second) // otherwise returns 0
@@ -1046,7 +1072,7 @@ class TracerSuite extends CatsEffectSuite {
     }
   }
 
-  test("nested SpanOps#surround for Tracer[StateT[IO, Int, *]]") {
+  test("nested SpanOps#surround for Tracer[IO].mapK[StateT[IO, Int, *]]") {
     TestControl.executeEmbed {
       for {
         now <- IO.monotonic.delayBy(1.second) // otherwise returns 0
@@ -1073,7 +1099,7 @@ class TracerSuite extends CatsEffectSuite {
     }
   }
 
-  test("nested SpanOps#surround for Tracer[Resource[IO, *]]") {
+  test("nested SpanOps#surround for Tracer[IO].mapK[Resource[IO, *]]") {
     TestControl.executeEmbed {
       for {
         now <- IO.monotonic.delayBy(1.second) // otherwise returns 0