diff --git a/build.sbt b/build.sbt
index 5f8966d3..96a94805 100644
--- a/build.sbt
+++ b/build.sbt
@@ -83,6 +83,7 @@ lazy val root = tlCrossRootProject.aggregate(
   datadog,
   log,
   newrelic,
+  mock,
   mtl,
   noop,
   xray,
@@ -331,7 +332,8 @@ lazy val mock = project
     description := "Mock Open Tracing implementation",
     libraryDependencies ++= Seq(
       "io.opentracing" % "opentracing-mock" % "0.33.0"
-    )
+    ),
+    tlVersionIntroduced := List("2.12", "2.13", "3").map(_ -> "0.3.1").toMap
   )
 
 lazy val examples = project
diff --git a/modules/mock/src/main/scala/MockEntryPoint.scala b/modules/mock/src/main/scala/MockEntryPoint.scala
index 03cdb0b0..5fe61ff4 100644
--- a/modules/mock/src/main/scala/MockEntryPoint.scala
+++ b/modules/mock/src/main/scala/MockEntryPoint.scala
@@ -5,8 +5,6 @@
 package natchez
 package mock
 
-import scala.jdk.CollectionConverters._
-
 import cats.effect.{Resource, Sync}
 import io.opentracing.mock.MockTracer
 import io.opentracing.propagation.{Format, TextMapAdapter}
@@ -15,21 +13,22 @@ final case class MockEntrypoint[F[_]: Sync]() extends EntryPoint[F] {
 
   val mockTracer = new MockTracer()
 
-  override def root(name: String): Resource[F, Span[F]] =
+  override def root(name: String, options: Span.Options): Resource[F, Span[F]] =
     Resource
       .make(Sync[F].delay(mockTracer.buildSpan(name).start()))(span => Sync[F].delay(span.finish()))
       .map(MockSpan(mockTracer, _))
 
   override def continue(
       name: String,
-      kernel: Kernel
+      kernel: Kernel,
+      options: Span.Options
   ): Resource[F, Span[F]] =
     Resource
       .make(
         Sync[F].delay {
           val spanCtxt = mockTracer.extract(
             Format.Builtin.HTTP_HEADERS,
-            new TextMapAdapter(kernel.toHeaders.asJava)
+            new TextMapAdapter(kernel.toJava)
           )
           mockTracer.buildSpan(name).asChildOf(spanCtxt).start()
         }
@@ -38,7 +37,8 @@ final case class MockEntrypoint[F[_]: Sync]() extends EntryPoint[F] {
 
   override def continueOrElseRoot(
       name: String,
-      kernel: Kernel
+      kernel: Kernel,
+      options: Span.Options
   ): Resource[F, Span[F]] =
     continue(name, kernel).flatMap {
       case null =>
diff --git a/modules/mock/src/main/scala/MockSpan.scala b/modules/mock/src/main/scala/MockSpan.scala
index 5302feae..ec10591e 100644
--- a/modules/mock/src/main/scala/MockSpan.scala
+++ b/modules/mock/src/main/scala/MockSpan.scala
@@ -27,7 +27,7 @@ final case class MockSpan[F[_]: Sync](tracer: ot.mock.MockTracer, span: ot.mock.
         Format.Builtin.HTTP_HEADERS,
         new TextMapAdapter(m)
       )
-      Kernel(m.asScala.toMap)
+      Kernel.fromJava(m)
     }
 
   def put(fields: (String, TraceValue)*): F[Unit] =
@@ -37,7 +37,7 @@ final case class MockSpan[F[_]: Sync](tracer: ot.mock.MockTracer, span: ot.mock.
       case (k, BooleanValue(v)) => Sync[F].delay(span.setTag(k, v))
     }
 
-  def attachError(err: Throwable): F[Unit] =
+  def attachError(err: Throwable, fields: (String, TraceValue)*): F[Unit] =
     put(
       Tags.ERROR.getKey -> true
     ) >>
@@ -61,7 +61,7 @@ final case class MockSpan[F[_]: Sync](tracer: ot.mock.MockTracer, span: ot.mock.
   override def log(event: String): F[Unit] =
     Sync[F].delay(span.log(event)).void
 
-  def span(name: String): Resource[F, Span[F]] =
+  def span(name: String, options: Span.Options): Resource[F, Span[F]] =
     Resource
       .make {
         Sync[F].delay(tracer.buildSpan(name).asChildOf(span).start)
@@ -72,7 +72,7 @@ final case class MockSpan[F[_]: Sync](tracer: ot.mock.MockTracer, span: ot.mock.
 
   def span(name: String, kernel: Kernel): Resource[F, Span[F]] = {
     val parent =
-      tracer.extract(Format.Builtin.HTTP_HEADERS, new TextMapAdapter(kernel.toHeaders.asJava))
+      tracer.extract(Format.Builtin.HTTP_HEADERS, new TextMapAdapter(kernel.toJava))
     Resource
       .make(Sync[F].delay(tracer.buildSpan(name).asChildOf(span).asChildOf(parent).start)) { s =>
         Sync[F].delay(s.finish())