diff --git a/.changes/1021e75a-45f3-4f3a-820c-700d9ec6e782.json b/.changes/1021e75a-45f3-4f3a-820c-700d9ec6e782.json
deleted file mode 100644
index 0fad5e0349..0000000000
--- a/.changes/1021e75a-45f3-4f3a-820c-700d9ec6e782.json
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-    "id": "1021e75a-45f3-4f3a-820c-700d9ec6e782",
-    "type": "bugfix",
-    "description": "Fix serialization of CBOR blobs"
-}
\ No newline at end of file
diff --git a/.changes/4820850c-8916-47f5-a7e1-8880e6a00d22.json b/.changes/4820850c-8916-47f5-a7e1-8880e6a00d22.json
deleted file mode 100644
index 297f7e603f..0000000000
--- a/.changes/4820850c-8916-47f5-a7e1-8880e6a00d22.json
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-    "id": "4820850c-8916-47f5-a7e1-8880e6a00d22",
-    "type": "bugfix",
-    "description": "Fix errors in equality checks for `CaseInsensitiveMap` which affect `Headers` and `ValuesMap` implementations"
-}
\ No newline at end of file
diff --git a/.changes/4855cecf-6a96-4622-b7ff-5d09e54f6564.json b/.changes/4855cecf-6a96-4622-b7ff-5d09e54f6564.json
new file mode 100644
index 0000000000..6c781606fe
--- /dev/null
+++ b/.changes/4855cecf-6a96-4622-b7ff-5d09e54f6564.json
@@ -0,0 +1,5 @@
+{
+    "id": "4855cecf-6a96-4622-b7ff-5d09e54f6564",
+    "type": "bugfix",
+    "description": "Overwrite `Content-Length` header rather than appending in `CrtHttpEngine`"
+}
\ No newline at end of file
diff --git a/.changes/7e4f8c08-941c-4ea5-91b3-4c284746c453.json b/.changes/7e4f8c08-941c-4ea5-91b3-4c284746c453.json
deleted file mode 100644
index 2b126708dd..0000000000
--- a/.changes/7e4f8c08-941c-4ea5-91b3-4c284746c453.json
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-    "id": "7e4f8c08-941c-4ea5-91b3-4c284746c453",
-    "type": "documentation",
-    "description": "Improve documentation for [`StandardRetryPolicy`](https://docs.aws.amazon.com/smithy-kotlin/api/latest/runtime-core/aws.smithy.kotlin.runtime.retries.policy/-standard-retry-policy/)"
-}
\ No newline at end of file
diff --git a/.changes/c0040355-ffdc-4813-80e9-baf859ef02b9.json b/.changes/c0040355-ffdc-4813-80e9-baf859ef02b9.json
deleted file mode 100644
index 42302b920d..0000000000
--- a/.changes/c0040355-ffdc-4813-80e9-baf859ef02b9.json
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-    "id": "c0040355-ffdc-4813-80e9-baf859ef02b9",
-    "type": "bugfix",
-    "description": "fix: correct hash code calculation for case-insensitive map entries"
-}
\ No newline at end of file
diff --git a/.changes/d3ce7511-6fb2-4435-8f46-db724551b384.json b/.changes/d3ce7511-6fb2-4435-8f46-db724551b384.json
deleted file mode 100644
index aa89d9167e..0000000000
--- a/.changes/d3ce7511-6fb2-4435-8f46-db724551b384.json
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-    "id": "d3ce7511-6fb2-4435-8f46-db724551b384",
-    "type": "misc",
-    "description": "Add telemetry provider configuration to `DefaultAwsSigner`"
-}
\ No newline at end of file
diff --git a/.github/workflows/api-compat-verification.yml b/.github/workflows/api-compat-verification.yml
index 2d4a22452a..5d7de9de0c 100644
--- a/.github/workflows/api-compat-verification.yml
+++ b/.github/workflows/api-compat-verification.yml
@@ -7,6 +7,8 @@ on:
       - main
       - '*-main'
 
+permissions: { }
+
 jobs:
   api-compat-verification:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/changelog-verification.yml b/.github/workflows/changelog-verification.yml
index bc9b81bded..ca9aaa3be7 100644
--- a/.github/workflows/changelog-verification.yml
+++ b/.github/workflows/changelog-verification.yml
@@ -4,7 +4,7 @@ permissions:
   id-token: write
 
 on:
-  pull_request_target:
+  pull_request:
     types: [ opened, synchronize, reopened, labeled, unlabeled ]
     branches:
       - main
diff --git a/.github/workflows/continuous-integration.yml b/.github/workflows/continuous-integration.yml
index da0bb593d6..40017ce513 100644
--- a/.github/workflows/continuous-integration.yml
+++ b/.github/workflows/continuous-integration.yml
@@ -8,6 +8,8 @@ on:
   pull_request:
   workflow_dispatch:
 
+permissions: { }
+
 # Allow one instance of this workflow per pull request, and cancel older runs when new changes are pushed
 concurrency:
   group: ci-pr-${{ github.ref }}
diff --git a/.github/workflows/issue-regression-labeler.yml b/.github/workflows/issue-regression-labeler.yml
index adecdbc628..97b857d60e 100644
--- a/.github/workflows/issue-regression-labeler.yml
+++ b/.github/workflows/issue-regression-labeler.yml
@@ -3,6 +3,7 @@ name: issue-regression-label
 on:
   issues:
     types: [opened, edited]
+permissions: { }
 jobs:
   add-regression-label:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/jreleaser.yml b/.github/workflows/jreleaser.yml
index 391e452d5d..93c5d7df6c 100644
--- a/.github/workflows/jreleaser.yml
+++ b/.github/workflows/jreleaser.yml
@@ -3,7 +3,7 @@
 name: JReleaser check
 on:
   pull_request:
-
+permissions: { }
 jobs:
   jreleaser-check:
     permissions: {}
diff --git a/.github/workflows/lint.yml b/.github/workflows/lint.yml
index c8c67eb7f7..66035c5757 100644
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -12,6 +12,8 @@ on:
       - '*-main'
   workflow_dispatch:
 
+permissions: { }
+
 env:
   PACKAGE_NAME: smithy-kotlin
 
diff --git a/.github/workflows/merge-main.yml b/.github/workflows/merge-main.yml
index b6316a2f38..7df49eda9a 100644
--- a/.github/workflows/merge-main.yml
+++ b/.github/workflows/merge-main.yml
@@ -3,7 +3,7 @@ on:
   push:
     branches: [ main ]
   workflow_dispatch:
-
+permissions: { }
 jobs:
   merge:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/minor-version-bump.yml b/.github/workflows/minor-version-bump.yml
new file mode 100644
index 0000000000..f7a36f8153
--- /dev/null
+++ b/.github/workflows/minor-version-bump.yml
@@ -0,0 +1,11 @@
+name: Minor version bump check
+on:
+  pull_request:
+permissions: { }
+jobs:
+  minor-version-bump-check:
+    permissions: {}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Minor version bump check
+        uses: awslabs/aws-kotlin-repo-tools/.github/actions/minor-version-bump@main
diff --git a/.github/workflows/release-readiness.yml b/.github/workflows/release-readiness.yml
index 26a880217f..baa20268a2 100644
--- a/.github/workflows/release-readiness.yml
+++ b/.github/workflows/release-readiness.yml
@@ -7,6 +7,8 @@ on:
   pull_request:
     branches: [ main ]
 
+permissions: { }
+
 jobs:
   release-readiness:
     if: ${{ !contains(github.event.pull_request.labels.*.name, 'ready-for-release') }}
diff --git a/.github/workflows/stale_issue.yaml b/.github/workflows/stale_issue.yaml
index c6f1cb933f..ad5b31742f 100644
--- a/.github/workflows/stale_issue.yaml
+++ b/.github/workflows/stale_issue.yaml
@@ -5,6 +5,8 @@ on:
   schedule:
   - cron: "0 0/3 * * *"
 
+permissions: { }
+
 jobs:
   cleanup:
     name: Stale issue job
diff --git a/.github/workflows/sync-mirror.yml b/.github/workflows/sync-mirror.yml
index edc80ce30c..7643881e56 100644
--- a/.github/workflows/sync-mirror.yml
+++ b/.github/workflows/sync-mirror.yml
@@ -5,6 +5,8 @@ on:
     branches: [ main ]
   workflow_dispatch:
 
+permissions: { }
+
 jobs:
   git-sync:
     # Only sync when pushing to source repo
diff --git a/CHANGELOG.md b/CHANGELOG.md
index b10da529c5..fd7a74d5ea 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Changelog
 
+## [1.5.10] - 09/22/2025
+
+### Documentation
+* Improve documentation for [`StandardRetryPolicy`](https://docs.aws.amazon.com/smithy-kotlin/api/latest/runtime-core/aws.smithy.kotlin.runtime.retries.policy/-standard-retry-policy/)
+
 ## [1.5.8] - 09/04/2025
 
 ## [1.5.7] - 09/04/2025
diff --git a/build.gradle.kts b/build.gradle.kts
index 2a900f2cda..951d4fdeb8 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -4,6 +4,7 @@
  */
 import aws.sdk.kotlin.gradle.dsl.configureJReleaser
 import aws.sdk.kotlin.gradle.dsl.configureLinting
+import aws.sdk.kotlin.gradle.dsl.configureMinorVersionStrategyRules
 import aws.sdk.kotlin.gradle.util.typedProp
 import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
 
@@ -109,6 +110,7 @@ val lintPaths = listOf(
 )
 
 configureLinting(lintPaths)
+configureMinorVersionStrategyRules(lintPaths)
 
 // Binary compatibility
 apiValidation {
diff --git a/gradle.properties b/gradle.properties
index c90e8aaef3..f7dfebfe89 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -14,10 +14,10 @@ kotlinx.atomicfu.enableNativeIrTransformation=false
 org.gradle.jvmargs=-Xmx2G -XX:MaxMetaspaceSize=1G
 
 # SDK
-sdkVersion=1.5.9-SNAPSHOT
+sdkVersion=1.5.11-SNAPSHOT
 
 # codegen
-codegenVersion=0.35.9-SNAPSHOT
+codegenVersion=0.35.11-SNAPSHOT
 
 # FIXME Remove after Dokka 2.0 Gradle plugin is stable
 org.jetbrains.dokka.experimental.gradle.pluginMode=V2Enabled
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 78f8d1bc05..44c0f0b92b 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -2,7 +2,7 @@
 kotlin-version = "2.2.0"
 dokka-version = "2.0.0"
 
-aws-kotlin-repo-tools-version = "0.4.56"
+aws-kotlin-repo-tools-version = "0.4.57"
 
 # libs
 coroutines-version = "1.10.2"
diff --git a/runtime/crt-util/jvm/src/aws/smithy/kotlin/runtime/crt/ReadChannelBodyStreamJvm.kt b/runtime/crt-util/jvm/src/aws/smithy/kotlin/runtime/crt/ReadChannelBodyStreamJvm.kt
index cb2e691167..7703ef5895 100644
--- a/runtime/crt-util/jvm/src/aws/smithy/kotlin/runtime/crt/ReadChannelBodyStreamJvm.kt
+++ b/runtime/crt-util/jvm/src/aws/smithy/kotlin/runtime/crt/ReadChannelBodyStreamJvm.kt
@@ -7,6 +7,5 @@ package aws.smithy.kotlin.runtime.crt
 
 import aws.sdk.kotlin.crt.io.MutableBuffer
 import aws.smithy.kotlin.runtime.io.SdkBuffer
-import aws.smithy.kotlin.runtime.io.read
 
 internal actual fun transferRequestBody(outgoing: SdkBuffer, dest: MutableBuffer) = outgoing.read(dest.buffer)
diff --git a/runtime/protocol/http-client-engines/http-client-engine-crt/jvmAndNative/src/aws/smithy/kotlin/runtime/http/engine/crt/RequestUtil.kt b/runtime/protocol/http-client-engines/http-client-engine-crt/jvmAndNative/src/aws/smithy/kotlin/runtime/http/engine/crt/RequestUtil.kt
index 5708f111b0..73f7d605a3 100644
--- a/runtime/protocol/http-client-engines/http-client-engine-crt/jvmAndNative/src/aws/smithy/kotlin/runtime/http/engine/crt/RequestUtil.kt
+++ b/runtime/protocol/http-client-engines/http-client-engine-crt/jvmAndNative/src/aws/smithy/kotlin/runtime/http/engine/crt/RequestUtil.kt
@@ -68,7 +68,7 @@ internal fun HttpRequest.toCrtRequest(callContext: CoroutineContext): aws.sdk.ko
     }
 
     val contentLength = body.contentLength?.takeIf { it >= 0 }?.toString() ?: headers[CONTENT_LENGTH_HEADER]
-    contentLength?.let { crtHeaders.append(CONTENT_LENGTH_HEADER, it) }
+    contentLength?.let { crtHeaders[CONTENT_LENGTH_HEADER] = it }
 
     return aws.sdk.kotlin.crt.http.HttpRequest(method.name, url.requestRelativePath, crtHeaders.build(), bodyStream)
 }
diff --git a/runtime/protocol/http-client-engines/http-client-engine-crt/jvmAndNative/test/aws/smithy/kotlin/runtime/http/engine/crt/RequestUtilTest.kt b/runtime/protocol/http-client-engines/http-client-engine-crt/jvmAndNative/test/aws/smithy/kotlin/runtime/http/engine/crt/RequestUtilTest.kt
index 25db47c70f..cb2d338588 100644
--- a/runtime/protocol/http-client-engines/http-client-engine-crt/jvmAndNative/test/aws/smithy/kotlin/runtime/http/engine/crt/RequestUtilTest.kt
+++ b/runtime/protocol/http-client-engines/http-client-engine-crt/jvmAndNative/test/aws/smithy/kotlin/runtime/http/engine/crt/RequestUtilTest.kt
@@ -4,7 +4,15 @@
  */
 package aws.smithy.kotlin.runtime.http.engine.crt
 
+import aws.smithy.kotlin.runtime.content.ByteStream
+import aws.smithy.kotlin.runtime.http.Headers
+import aws.smithy.kotlin.runtime.http.HttpMethod
+import aws.smithy.kotlin.runtime.http.request.HttpRequest
+import aws.smithy.kotlin.runtime.http.toHttpBody
+import aws.smithy.kotlin.runtime.net.url.Url
+import kotlinx.coroutines.test.runTest
 import kotlin.test.Test
+import kotlin.test.assertEquals
 import kotlin.test.assertFalse
 import kotlin.test.assertTrue
 
@@ -42,4 +50,19 @@ class RequestUtilTest {
             assertFalse(isRetryable(code, name), "Expected $name to not be retryable!")
         }
     }
+
+    @Test
+    fun testContentLengthHeader() = runTest {
+        val data = "a".repeat(100)
+
+        val request = HttpRequest(
+            HttpMethod.POST,
+            url = Url.parse("https://notarealurl.com"),
+            headers = Headers { set("Content-Length", data.length.toString()) },
+            body = ByteStream.fromString(data).toHttpBody(),
+        )
+
+        val crtRequest = request.toCrtRequest(coroutineContext)
+        assertEquals(listOf(data.length.toString()), crtRequest.headers.getAll("Content-Length"))
+    }
 }
diff --git a/runtime/protocol/http-client-engines/http-client-engine-okhttp/jvm/test/aws/smithy/kotlin/runtime/http/engine/okhttp/OkHttpRequestTest.kt b/runtime/protocol/http-client-engines/http-client-engine-okhttp/jvm/test/aws/smithy/kotlin/runtime/http/engine/okhttp/OkHttpRequestTest.kt
index 16f6773008..760a947308 100644
--- a/runtime/protocol/http-client-engines/http-client-engine-okhttp/jvm/test/aws/smithy/kotlin/runtime/http/engine/okhttp/OkHttpRequestTest.kt
+++ b/runtime/protocol/http-client-engines/http-client-engine-okhttp/jvm/test/aws/smithy/kotlin/runtime/http/engine/okhttp/OkHttpRequestTest.kt
@@ -5,6 +5,7 @@
 
 package aws.smithy.kotlin.runtime.http.engine.okhttp
 
+import aws.smithy.kotlin.runtime.content.ByteStream
 import aws.smithy.kotlin.runtime.http.*
 import aws.smithy.kotlin.runtime.http.engine.internal.HttpClientMetrics
 import aws.smithy.kotlin.runtime.http.request.HttpRequest
@@ -71,6 +72,22 @@ class OkHttpRequestTest {
         assertEquals(listOf("bar", "baz"), actual.headers("FoO"))
     }
 
+    @Test
+    fun itConvertsContentLengthHeader() {
+        val data = "a".repeat(100)
+        val url = Url.parse("https://aws.amazon.com")
+        val headers = Headers {
+            append("Content-Length", data.length.toString())
+        }
+        val request = HttpRequest(HttpMethod.POST, url, headers, ByteStream.fromString(data).toHttpBody())
+
+        val execContext = ExecutionContext()
+        val actual = request.toOkHttpRequest(execContext, EmptyCoroutineContext, testMetrics)
+
+        assertTrue(actual.headers.size >= 1)
+        assertEquals(listOf(data.length.toString()), actual.headers("Content-Length"))
+    }
+
     @Test
     fun itSupportsNonAsciiHeaderValues() {
         val url = Url.parse("https://aws.amazon.com")
diff --git a/runtime/runtime-core/api/runtime-core.api b/runtime/runtime-core/api/runtime-core.api
index 597cdafe81..0e8f85de3a 100644
--- a/runtime/runtime-core/api/runtime-core.api
+++ b/runtime/runtime-core/api/runtime-core.api
@@ -39,6 +39,11 @@ public abstract interface annotation class aws/smithy/kotlin/runtime/IgnoreNativ
 public abstract interface annotation class aws/smithy/kotlin/runtime/InternalApi : java/lang/annotation/Annotation {
 }
 
+public abstract interface annotation class aws/smithy/kotlin/runtime/PlannedRemoval : java/lang/annotation/Annotation {
+	public abstract fun major ()I
+	public abstract fun minor ()I
+}
+
 public abstract interface class aws/smithy/kotlin/runtime/ProtocolResponse {
 	public abstract fun getSummary ()Ljava/lang/String;
 }
@@ -391,6 +396,7 @@ public final class aws/smithy/kotlin/runtime/content/BigDecimal : java/lang/Numb
 	public final fun floatValue ()F
 	public final fun getExponent ()I
 	public final fun getMantissa ()Laws/smithy/kotlin/runtime/content/BigInteger;
+	public final fun getValue ()Ljava/lang/String;
 	public fun hashCode ()I
 	public final fun intValue ()I
 	public final fun longValue ()J
@@ -416,6 +422,7 @@ public final class aws/smithy/kotlin/runtime/content/BigInteger : java/lang/Numb
 	public final fun doubleValue ()D
 	public fun equals (Ljava/lang/Object;)Z
 	public final fun floatValue ()F
+	public final fun getValue ()Ljava/lang/String;
 	public fun hashCode ()I
 	public final fun intValue ()I
 	public final fun longValue ()J
@@ -864,10 +871,6 @@ public final class aws/smithy/kotlin/runtime/io/HashingSource : aws/smithy/kotli
 }
 
 public final class aws/smithy/kotlin/runtime/io/JavaIOKt {
-	public static final fun inputStream (Laws/smithy/kotlin/runtime/io/SdkBuffer;)Ljava/io/InputStream;
-	public static final fun isOpen (Laws/smithy/kotlin/runtime/io/SdkBuffer;)Z
-	public static final fun outputStream (Laws/smithy/kotlin/runtime/io/SdkBuffer;)Ljava/io/OutputStream;
-	public static final fun read (Laws/smithy/kotlin/runtime/io/SdkBuffer;Ljava/nio/ByteBuffer;)I
 	public static final fun sink (Ljava/io/File;)Laws/smithy/kotlin/runtime/io/SdkSink;
 	public static final fun sink (Ljava/io/OutputStream;)Laws/smithy/kotlin/runtime/io/SdkSink;
 	public static final fun sink (Ljava/nio/file/Path;)Laws/smithy/kotlin/runtime/io/SdkSink;
@@ -878,7 +881,6 @@ public final class aws/smithy/kotlin/runtime/io/JavaIOKt {
 	public static final fun source (Ljava/nio/file/Path;Lkotlin/ranges/LongRange;)Laws/smithy/kotlin/runtime/io/SdkSource;
 	public static synthetic fun source$default (Ljava/io/File;JJILjava/lang/Object;)Laws/smithy/kotlin/runtime/io/SdkSource;
 	public static synthetic fun source$default (Ljava/nio/file/Path;JJILjava/lang/Object;)Laws/smithy/kotlin/runtime/io/SdkSource;
-	public static final fun write (Laws/smithy/kotlin/runtime/io/SdkBuffer;Ljava/nio/ByteBuffer;)I
 }
 
 public final class aws/smithy/kotlin/runtime/io/SdkBuffer : aws/smithy/kotlin/runtime/io/SdkBufferedSink, aws/smithy/kotlin/runtime/io/SdkBufferedSource {
@@ -891,8 +893,12 @@ public final class aws/smithy/kotlin/runtime/io/SdkBuffer : aws/smithy/kotlin/ru
 	public fun getBuffer ()Laws/smithy/kotlin/runtime/io/SdkBuffer;
 	public final fun getSize ()J
 	public fun hashCode ()I
+	public fun inputStream ()Ljava/io/InputStream;
+	public fun isOpen ()Z
+	public fun outputStream ()Ljava/io/OutputStream;
 	public fun peek ()Laws/smithy/kotlin/runtime/io/SdkBufferedSource;
 	public fun read (Laws/smithy/kotlin/runtime/io/SdkBuffer;J)J
+	public fun read (Ljava/nio/ByteBuffer;)I
 	public fun read ([BII)I
 	public fun readAll (Laws/smithy/kotlin/runtime/io/SdkSink;)J
 	public fun readByte ()B
@@ -912,6 +918,7 @@ public final class aws/smithy/kotlin/runtime/io/SdkBuffer : aws/smithy/kotlin/ru
 	public fun toString ()Ljava/lang/String;
 	public fun write (Laws/smithy/kotlin/runtime/io/SdkBuffer;J)V
 	public fun write (Laws/smithy/kotlin/runtime/io/SdkSource;J)V
+	public fun write (Ljava/nio/ByteBuffer;)I
 	public fun write ([BII)V
 	public fun writeAll (Laws/smithy/kotlin/runtime/io/SdkSource;)J
 	public fun writeByte (B)V
@@ -924,9 +931,11 @@ public final class aws/smithy/kotlin/runtime/io/SdkBuffer : aws/smithy/kotlin/ru
 	public fun writeUtf8 (Ljava/lang/String;II)V
 }
 
-public abstract interface class aws/smithy/kotlin/runtime/io/SdkBufferedSink : aws/smithy/kotlin/runtime/io/SdkSink {
+public abstract interface class aws/smithy/kotlin/runtime/io/SdkBufferedSink : aws/smithy/kotlin/runtime/io/SdkSink, java/nio/channels/WritableByteChannel {
 	public abstract fun emit ()V
+	public abstract fun flush ()V
 	public abstract fun getBuffer ()Laws/smithy/kotlin/runtime/io/SdkBuffer;
+	public abstract fun outputStream ()Ljava/io/OutputStream;
 	public abstract fun write (Laws/smithy/kotlin/runtime/io/SdkSource;J)V
 	public abstract fun write ([BII)V
 	public static synthetic fun write$default (Laws/smithy/kotlin/runtime/io/SdkBufferedSink;[BIIILjava/lang/Object;)V
@@ -947,9 +956,10 @@ public final class aws/smithy/kotlin/runtime/io/SdkBufferedSink$DefaultImpls {
 	public static synthetic fun writeUtf8$default (Laws/smithy/kotlin/runtime/io/SdkBufferedSink;Ljava/lang/String;IIILjava/lang/Object;)V
 }
 
-public abstract interface class aws/smithy/kotlin/runtime/io/SdkBufferedSource : aws/smithy/kotlin/runtime/io/SdkSource {
+public abstract interface class aws/smithy/kotlin/runtime/io/SdkBufferedSource : aws/smithy/kotlin/runtime/io/SdkSource, java/nio/channels/ReadableByteChannel {
 	public abstract fun exhausted ()Z
 	public abstract fun getBuffer ()Laws/smithy/kotlin/runtime/io/SdkBuffer;
+	public abstract fun inputStream ()Ljava/io/InputStream;
 	public abstract fun peek ()Laws/smithy/kotlin/runtime/io/SdkBufferedSource;
 	public abstract fun read ([BII)I
 	public static synthetic fun read$default (Laws/smithy/kotlin/runtime/io/SdkBufferedSource;[BIIILjava/lang/Object;)I
diff --git a/runtime/runtime-core/common/src/aws/smithy/kotlin/runtime/Annotations.kt b/runtime/runtime-core/common/src/aws/smithy/kotlin/runtime/Annotations.kt
index 30eed9afe4..fa8022f0fd 100644
--- a/runtime/runtime-core/common/src/aws/smithy/kotlin/runtime/Annotations.kt
+++ b/runtime/runtime-core/common/src/aws/smithy/kotlin/runtime/Annotations.kt
@@ -59,6 +59,19 @@ public annotation class ExperimentalApi
 @DslMarker
 public annotation class SdkDsl
 
+/**
+ * Indicates that the annotated API is deprecated and scheduled for removal in an upcoming version.
+ * Any code using this API should migrate to the suggested replacement as soon as possible.
+ */
+@RequiresOptIn(
+    message = "This API is deprecated and scheduled for removal in an upcoming version.",
+    level = RequiresOptIn.Level.WARNING,
+)
+public annotation class PlannedRemoval(
+    val major: Int,
+    val minor: Int,
+)
+
 /**
  * Marks a test that should be ignored on Native platforms
  */
diff --git a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/content/BigDecimalJVM.kt b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/content/BigDecimalJVM.kt
index a7de1ab953..3890cfa9d9 100644
--- a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/content/BigDecimalJVM.kt
+++ b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/content/BigDecimalJVM.kt
@@ -45,6 +45,8 @@ public actual class BigDecimal private constructor(private val delegate: JvmBigD
     public actual val exponent: Int
         get() = delegate.scale()
 
+    public val value: String = delegate.toString()
+
     public actual operator fun plus(other: BigDecimal): BigDecimal =
         coalesceOrCreate(delegate + other.delegate, this, other)
 
diff --git a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/content/BigIntegerJVM.kt b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/content/BigIntegerJVM.kt
index 2f864710b3..738d5ed102 100644
--- a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/content/BigIntegerJVM.kt
+++ b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/content/BigIntegerJVM.kt
@@ -35,6 +35,7 @@ public actual class BigInteger internal constructor(internal val delegate: JvmBi
     public actual override fun toDouble(): Double = delegate.toDouble()
     public actual override fun toString(): String = toString(10)
     public actual fun toString(radix: Int): String = delegate.toString(radix)
+    public val value: String = delegate.toString()
 
     public actual override fun hashCode(): Int = 17 + delegate.hashCode()
     public actual override fun equals(other: Any?): Boolean = other is BigInteger && delegate == other.delegate
diff --git a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/BufferedSinkAdapterJVM.kt b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/BufferedSinkAdapterJVM.kt
new file mode 100644
index 0000000000..404dd6d078
--- /dev/null
+++ b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/BufferedSinkAdapterJVM.kt
@@ -0,0 +1,20 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package aws.smithy.kotlin.runtime.io
+
+import java.io.OutputStream
+import java.nio.ByteBuffer
+
+internal actual class BufferedSinkAdapter actual constructor(
+    sink: okio.BufferedSink,
+) : AbstractBufferedSinkAdapter(sink),
+    SdkBufferedSink {
+    override fun write(src: ByteBuffer): Int = delegate.write(src)
+
+    override fun isOpen(): Boolean = delegate.isOpen
+
+    override fun outputStream(): OutputStream = delegate.outputStream()
+}
diff --git a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/BufferedSourceAdapterJVM.kt b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/BufferedSourceAdapterJVM.kt
new file mode 100644
index 0000000000..e7b1c3d759
--- /dev/null
+++ b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/BufferedSourceAdapterJVM.kt
@@ -0,0 +1,21 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package aws.smithy.kotlin.runtime.io
+
+import java.io.InputStream
+import java.nio.ByteBuffer
+
+internal actual class BufferedSourceAdapter actual constructor(
+    source: okio.BufferedSource,
+) : AbstractBufferedSourceAdapter(source),
+    SdkBufferedSource {
+
+    override fun read(dst: ByteBuffer): Int = delegate.read(dst)
+
+    override fun isOpen(): Boolean = delegate.isOpen
+
+    override fun inputStream(): InputStream = delegate.inputStream()
+}
diff --git a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/JavaIO.kt b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/JavaIO.kt
index c035aa9a4c..e7578bfea4 100644
--- a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/JavaIO.kt
+++ b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/JavaIO.kt
@@ -9,7 +9,6 @@ import aws.smithy.kotlin.runtime.io.internal.toSdk
 import java.io.File
 import java.io.InputStream
 import java.io.OutputStream
-import java.nio.ByteBuffer
 import java.nio.file.Path
 import okio.sink as okioSink
 import okio.source as okioSource
@@ -60,20 +59,3 @@ public fun InputStream.source(): SdkSource = okioSource().toSdk()
  * Create a new [SdkSource] that reads from this [InputStream]
  */
 public fun OutputStream.sink(): SdkSink = okioSink().toSdk()
-
-// BufferedSinkAdapter
-internal fun BufferedSinkAdapter.outputStream(): OutputStream = delegate.outputStream()
-internal fun BufferedSinkAdapter.write(src: ByteBuffer): Int = delegate.write(src)
-internal fun BufferedSinkAdapter.isOpen(): Boolean = delegate.isOpen
-
-// BufferedSourceAdapter
-internal fun BufferedSourceAdapter.read(dst: ByteBuffer): Int = delegate.read(dst)
-internal fun BufferedSourceAdapter.isOpen(): Boolean = delegate.isOpen
-internal fun BufferedSourceAdapter.inputStream(): InputStream = delegate.inputStream()
-
-// SdkBuffer
-public fun SdkBuffer.read(dst: ByteBuffer): Int = wrapOkio { inner.read(dst) }
-public fun SdkBuffer.write(src: ByteBuffer): Int = wrapOkio { inner.write(src) }
-public fun SdkBuffer.isOpen(): Boolean = inner.isOpen
-public fun SdkBuffer.inputStream(): InputStream = inner.inputStream()
-public fun SdkBuffer.outputStream(): OutputStream = inner.outputStream()
diff --git a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/SdkBufferJVM.kt b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/SdkBufferJVM.kt
new file mode 100644
index 0000000000..c2f486c3c9
--- /dev/null
+++ b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/SdkBufferJVM.kt
@@ -0,0 +1,122 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package aws.smithy.kotlin.runtime.io
+
+import aws.smithy.kotlin.runtime.io.internal.*
+import java.io.InputStream
+import java.io.OutputStream
+import java.nio.ByteBuffer
+
+// FIXME Commonize with Native after removing WritableByteStream / ReadableByteStream in 1.6.x
+public actual class SdkBuffer :
+    SdkBufferedSource,
+    SdkBufferedSink {
+    public actual constructor() : this(okio.Buffer())
+
+    internal actual val inner: okio.Buffer
+
+    internal actual constructor(buffer: okio.Buffer) {
+        this.inner = buffer
+    }
+
+    public actual val size: Long
+        get() = inner.size
+
+    actual override val buffer: SdkBuffer
+        get() = this
+
+    override fun toString(): String = inner.toString()
+
+    override fun hashCode(): Int = inner.hashCode()
+
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (other !is SdkBuffer) return false
+        return inner == other.inner
+    }
+
+    actual override fun skip(byteCount: Long): Unit = commonSkip(byteCount)
+
+    actual override fun readByte(): Byte = commonReadByte()
+
+    actual override fun readShort(): Short = commonReadShort()
+
+    actual override fun readShortLe(): Short = commonReadShortLe()
+
+    actual override fun readLong(): Long = commonReadLong()
+
+    actual override fun readLongLe(): Long = commonReadLongLe()
+
+    actual override fun readInt(): Int = commonReadInt()
+
+    actual override fun readIntLe(): Int = commonReadIntLe()
+
+    actual override fun readAll(sink: SdkSink): Long = commonReadAll(sink)
+
+    actual override fun read(sink: ByteArray, offset: Int, limit: Int): Int =
+        commonRead(sink, offset, limit)
+
+    actual override fun read(sink: SdkBuffer, limit: Long): Long =
+        commonRead(sink, limit)
+
+    override fun read(dst: ByteBuffer): Int = inner.read(dst)
+
+    actual override fun readByteArray(): ByteArray = commonReadByteArray()
+
+    actual override fun readByteArray(byteCount: Long): ByteArray = commonReadByteArray(byteCount)
+
+    actual override fun readUtf8(): String = commonReadUtf8()
+
+    actual override fun readUtf8(byteCount: Long): String = commonReadUtf8(byteCount)
+
+    actual override fun peek(): SdkBufferedSource = commonPeek()
+
+    actual override fun exhausted(): Boolean = commonExhausted()
+    actual override fun request(byteCount: Long): Boolean = commonRequest(byteCount)
+
+    actual override fun require(byteCount: Long): Unit = commonRequire(byteCount)
+
+    actual override fun write(source: ByteArray, offset: Int, limit: Int): Unit =
+        commonWrite(source, offset, limit)
+
+    actual override fun write(source: SdkSource, byteCount: Long): Unit =
+        commonWrite(source, byteCount)
+
+    actual override fun write(source: SdkBuffer, byteCount: Long): Unit =
+        commonWrite(source, byteCount)
+
+    override fun write(src: ByteBuffer): Int = inner.write(src)
+
+    actual override fun writeAll(source: SdkSource): Long = commonWriteAll(source)
+
+    actual override fun writeUtf8(string: String, start: Int, endExclusive: Int): Unit =
+        commonWriteUtf8(string, start, endExclusive)
+
+    actual override fun writeByte(x: Byte): Unit = commonWriteByte(x)
+
+    actual override fun writeShort(x: Short): Unit = commonWriteShort(x)
+
+    actual override fun writeShortLe(x: Short): Unit = commonWriteShortLe(x)
+
+    actual override fun writeInt(x: Int): Unit = commonWriteInt(x)
+
+    actual override fun writeIntLe(x: Int): Unit = commonWriteIntLe(x)
+
+    actual override fun writeLong(x: Long): Unit = commonWriteLong(x)
+
+    actual override fun writeLongLe(x: Long): Unit = commonWriteLongLe(x)
+
+    actual override fun flush(): Unit = commonFlush()
+
+    actual override fun emit() {
+        inner.emit()
+    }
+    actual override fun close(): Unit = commonClose()
+    override fun isOpen(): Boolean = inner.isOpen
+
+    override fun inputStream(): InputStream = inner.inputStream()
+    override fun outputStream(): OutputStream = inner.outputStream()
+}
diff --git a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/SdkBufferedSinkJVM.kt b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/SdkBufferedSinkJVM.kt
new file mode 100644
index 0000000000..6a44c557a3
--- /dev/null
+++ b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/SdkBufferedSinkJVM.kt
@@ -0,0 +1,109 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package aws.smithy.kotlin.runtime.io
+
+import java.io.OutputStream
+import java.nio.channels.WritableByteChannel
+import kotlin.jvm.Throws
+
+/**
+ * A sink that keeps a buffer internally so that callers can do small writes without
+ * a performance penalty.
+ */
+public actual sealed interface SdkBufferedSink :
+    SdkSink,
+    WritableByteChannel {
+    /**
+     * The underlying buffer for this sink
+     */
+    public actual val buffer: SdkBuffer
+
+    /**
+     * Write [limit] bytes from [source] starting at [offset]
+     */
+    @Throws(IOException::class)
+    public actual fun write(source: ByteArray, offset: Int, limit: Int): Unit
+
+    /**
+     * Write all bytes from [source] to this sink.
+     * @return the number of bytes read which will be 0 if [source] is exhausted
+     */
+    @Throws(IOException::class)
+    public actual fun writeAll(source: SdkSource): Long
+
+    /**
+     * Removes [byteCount] bytes from [source] and writes them to this sink.
+     */
+    @Throws(IOException::class)
+    public actual fun write(source: SdkSource, byteCount: Long): Unit
+
+    /**
+     * Write UTF8-bytes of [string] to this sink starting at [start] index up to [endExclusive] index.
+     */
+    @Throws(IOException::class)
+    public actual fun writeUtf8(string: String, start: Int, endExclusive: Int): Unit
+
+    /**
+     * Writes byte [x] to this sink
+     */
+    @Throws(IOException::class)
+    public actual fun writeByte(x: Byte): Unit
+
+    /**
+     * Writes short [x] as a big-endian bytes to this sink
+     */
+    @Throws(IOException::class)
+    public actual fun writeShort(x: Short): Unit
+
+    /**
+     * Writes short [x] as a little-endian bytes to this sink
+     */
+    @Throws(IOException::class)
+    public actual fun writeShortLe(x: Short): Unit
+
+    /**
+     * Writes int [x] as a big-endian bytes to this sink
+     */
+    @Throws(IOException::class)
+    public actual fun writeInt(x: Int): Unit
+
+    /**
+     * Writes int [x] as a little-endian bytes to this sink
+     */
+    @Throws(IOException::class)
+    public actual fun writeIntLe(x: Int): Unit
+
+    /**
+     * Writes long [x] as a big-endian bytes to this sink
+     */
+    @Throws(IOException::class)
+    public actual fun writeLong(x: Long): Unit
+
+    /**
+     * Writes long [x] as a little-endian bytes to this sink
+     */
+    @Throws(IOException::class)
+    public actual fun writeLongLe(x: Long): Unit
+
+    /**
+     * Return an output stream that writes to this sink
+     */
+    public fun outputStream(): OutputStream
+
+    /**
+     * Writes all buffered data to the underlying sink.
+     */
+    @Throws(IOException::class)
+    actual override fun flush(): Unit
+
+    /**
+     * Writes all buffered data to the underlying sink. Like flush, but weaker (ensures data is pushed to the
+     * underlying sink but not necessarily all the way down the chain like [flush] does). Call before this sink
+     * goes out of scope to ensure any buffered data eventually gets to its final destination
+     */
+    @Throws(IOException::class)
+    public actual fun emit(): Unit
+}
diff --git a/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/SdkBufferedSourceJVM.kt b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/SdkBufferedSourceJVM.kt
new file mode 100644
index 0000000000..076502f7c5
--- /dev/null
+++ b/runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/io/SdkBufferedSourceJVM.kt
@@ -0,0 +1,144 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package aws.smithy.kotlin.runtime.io
+
+import java.io.InputStream
+import java.nio.channels.ReadableByteChannel
+
+public actual sealed interface SdkBufferedSource :
+    SdkSource,
+    ReadableByteChannel {
+
+    /**
+     * The underlying buffer for this source
+     */
+    public actual val buffer: SdkBuffer
+
+    /**
+     * Discards [byteCount] bytes from this source. Throws [IOException] if source is exhausted before [byteCount]
+     * bytes can be discarded.
+     */
+    @Throws(IOException::class)
+    public actual fun skip(byteCount: Long)
+
+    /**
+     * Read a single byte from this source and return it
+     */
+    @Throws(IOException::class)
+    public actual fun readByte(): Byte
+
+    /**
+     * Read two bytes in big-endian order from this source and returns them as a short.
+     */
+    @Throws(IOException::class)
+    public actual fun readShort(): Short
+
+    /**
+     * Read two bytes in little-endian order from this source and returns them as a short.
+     */
+    @Throws(IOException::class)
+    public actual fun readShortLe(): Short
+
+    /**
+     * Read eight bytes in big-endian order from this source and returns them as a long.
+     */
+    @Throws(IOException::class)
+    public actual fun readLong(): Long
+
+    /**
+     * Read eight bytes in little-endian order from this source and returns them as a long.
+     */
+    @Throws(IOException::class)
+    public actual fun readLongLe(): Long
+
+    /**
+     * Read four bytes in big-endian order from this source and returns them as an int.
+     */
+    @Throws(IOException::class)
+    public actual fun readInt(): Int
+
+    /**
+     * Read four bytes in little-endian order from this source and returns them as an int.
+     */
+    @Throws(IOException::class)
+    public actual fun readIntLe(): Int
+
+    /**
+     * Reads all bytes from this and appends them to [sink]. Returns
+     * the total number of bytes written which will be 0 if this source
+     * is exhausted.
+     */
+    @Throws(IOException::class)
+    public actual fun readAll(sink: SdkSink): Long
+
+    /**
+     * Read up to [limit] bytes and write them to [sink] starting at [offset]
+     */
+    @Throws(IOException::class)
+    public actual fun read(sink: ByteArray, offset: Int, limit: Int): Int
+
+    /**
+     * Reads all bytes from this source and returns them as a byte array
+     *
+     * **Caution** This may pull a large amount of data into memory, only do this if you are sure
+     * the contents fit into memory. Throws [IllegalArgumentException] if the buffer size exceeds [Int.MAX_VALUE].
+     */
+    @Throws(IOException::class)
+    public actual fun readByteArray(): ByteArray
+
+    /**
+     * Reads [byteCount] bytes from this source and returns them as a byte array
+     */
+    @Throws(IOException::class)
+    public actual fun readByteArray(byteCount: Long): ByteArray
+
+    /**
+     * Reads all bytes from this source, decodes them as UTF-8, and returns the string.
+     *
+     * **Caution** This may pull a large amount of data into memory, only do this if you are sure
+     * the contents fit into memory. Throws [IllegalArgumentException] if the buffer size exceeds [Int.MAX_VALUE].
+     */
+    @Throws(IOException::class)
+    public actual fun readUtf8(): String
+
+    /**
+     * Reads [byteCount] bytes from this source, decodes them as UTF-8, and returns the string.
+     */
+    @Throws(IOException::class)
+    public actual fun readUtf8(byteCount: Long): String
+
+    /**
+     * Get an input stream that reads from this source
+     */
+    public fun inputStream(): InputStream
+
+    /**
+     * Returns a new [SdkBufferedSource] that can read data from this source
+     * without consuming it. The returned source becomes invalid once this source is next
+     * read or closed.
+     */
+    public actual fun peek(): SdkBufferedSource
+
+    /**
+     * Returns true if there are no more bytes in this source. This will block until there are bytes
+     * to read or the source is definitely exhausted.
+     */
+    public actual fun exhausted(): Boolean
+
+    /**
+     * Returns true when the buffer contains at least [byteCount] bytes. False if the source
+     * is exhausted before the requested number of bytes could be read
+     */
+    @Throws(IOException::class)
+    public actual fun request(byteCount: Long): Boolean
+
+    /**
+     * Returns when the buffer contains at least [byteCount] bytes or throws [EOFException]
+     * if the source is exhausted before the requested number of bytes could be read
+     */
+    @Throws(IOException::class)
+    public actual fun require(byteCount: Long): Unit
+}
diff --git a/runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/BufferedSinkAdapterJvmAndNative.kt b/runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/BufferedSinkAdapterNative.kt
similarity index 83%
rename from runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/BufferedSinkAdapterJvmAndNative.kt
rename to runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/BufferedSinkAdapterNative.kt
index 7205c8d6a1..bf5767cf35 100644
--- a/runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/BufferedSinkAdapterJvmAndNative.kt
+++ b/runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/BufferedSinkAdapterNative.kt
@@ -4,9 +4,6 @@
  */
 package aws.smithy.kotlin.runtime.io
 
-import aws.smithy.kotlin.runtime.InternalApi
-
-@InternalApi
 internal actual class BufferedSinkAdapter actual constructor(sink: okio.BufferedSink) :
     AbstractBufferedSinkAdapter(sink),
     SdkBufferedSink
diff --git a/runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/BufferedSourceAdapterJvmAndNative.kt b/runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/BufferedSourceAdapterNative.kt
similarity index 100%
rename from runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/BufferedSourceAdapterJvmAndNative.kt
rename to runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/BufferedSourceAdapterNative.kt
diff --git a/runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/SdkBufferJvmAndNative.kt b/runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/SdkBufferNative.kt
similarity index 97%
rename from runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/SdkBufferJvmAndNative.kt
rename to runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/SdkBufferNative.kt
index c0472cd857..616ef39a76 100644
--- a/runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/SdkBufferJvmAndNative.kt
+++ b/runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/SdkBufferNative.kt
@@ -6,6 +6,7 @@ package aws.smithy.kotlin.runtime.io
 
 import aws.smithy.kotlin.runtime.io.internal.*
 
+// FIXME Commonize with JVM after removing WritableByteStream / ReadableByteStream in 1.6.x
 public actual class SdkBuffer :
     SdkBufferedSource,
     SdkBufferedSink {
diff --git a/runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/SdkBufferedSinkJvmAndNative.kt b/runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/SdkBufferedSinkNative.kt
similarity index 100%
rename from runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/SdkBufferedSinkJvmAndNative.kt
rename to runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/SdkBufferedSinkNative.kt
diff --git a/runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/SdkBufferedSourceJvmAndNative.kt b/runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/SdkBufferedSourceNative.kt
similarity index 100%
rename from runtime/runtime-core/jvmAndNative/src/aws/smithy/kotlin/runtime/io/SdkBufferedSourceJvmAndNative.kt
rename to runtime/runtime-core/native/src/aws/smithy/kotlin/runtime/io/SdkBufferedSourceNative.kt