diff --git a/core/src/main/scala/org/apache/spark/rdd/SequenceFileRDDFunctions.scala b/core/src/main/scala/org/apache/spark/rdd/SequenceFileRDDFunctions.scala
index 02def89dd8..2f6ff0acdf 100644
--- a/core/src/main/scala/org/apache/spark/rdd/SequenceFileRDDFunctions.scala
+++ b/core/src/main/scala/org/apache/spark/rdd/SequenceFileRDDFunctions.scala
@@ -32,16 +32,13 @@ import org.apache.spark.internal.Logging
  * @note This can't be part of PairRDDFunctions because we need more implicit parameters to
  * convert our keys and values to Writable.
  */
-class SequenceFileRDDFunctions[K <% Writable: ClassTag, V <% Writable : ClassTag](
+class SequenceFileRDDFunctions[K: IsWritable: ClassTag, V: IsWritable: ClassTag](
     self: RDD[(K, V)],
     _keyWritableClass: Class[_ <: Writable],
     _valueWritableClass: Class[_ <: Writable])
   extends Logging
   with Serializable {
 
-  // TODO the context bound (<%) above should be replaced with simple type bound and implicit
-  // conversion but is a breaking change. This should be fixed in Spark 3.x.
-
   /**
    * Output the RDD as a Hadoop SequenceFile using the Writable types we infer from the RDD's key
    * and value types. If the key or value are Writable, then we use their classes directly;
@@ -52,7 +49,7 @@ class SequenceFileRDDFunctions[K <% Writable: ClassTag, V <% Writable : ClassTag
   def saveAsSequenceFile(
       path: String,
       codec: Option[Class[_ <: CompressionCodec]] = None): Unit = self.withScope {
-    def anyToWritable[U <% Writable](u: U): Writable = u
+    def anyToWritable[U: IsWritable](u: U): Writable = u
 
     // TODO We cannot force the return type of `anyToWritable` be same as keyWritableClass and
     // valueWritableClass at the compile time. To implement that, we need to add type parameters to
diff --git a/core/src/main/scala/org/apache/spark/rdd/package.scala b/core/src/main/scala/org/apache/spark/rdd/package.scala
index 55fc6e4d2b..43ca6d7643 100644
--- a/core/src/main/scala/org/apache/spark/rdd/package.scala
+++ b/core/src/main/scala/org/apache/spark/rdd/package.scala
@@ -17,7 +17,11 @@
 
 package org.apache.spark
 
+import org.apache.hadoop.io.Writable
+
 /**
  * Provides several RDD implementations. See [[org.apache.spark.rdd.RDD]].
  */
-package object rdd
+package object rdd {
+  type IsWritable[A] = A => Writable
+}