diff --git a/build.gradle.kts b/build.gradle.kts
index 6d30b75..2be3897 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -6,7 +6,7 @@ plugins {
     `java-library`
     `maven-publish`
 
-    id("org.jmailen.kotlinter") version "2.3.2"
+    id("org.jmailen.kotlinter") version "2.4.1"
     id("org.jetbrains.dokka") version "0.10.1"
 }
 
@@ -19,17 +19,16 @@ repositories {
 dependencies {
     val kotlinVersion = "1.3.72"
     implementation(kotlin("stdlib-jdk8", kotlinVersion))
-    implementation(kotlin("reflect", kotlinVersion))
 
     implementation(kotlin("test", kotlinVersion))
     implementation(kotlin("test-junit", kotlinVersion))
 
-    val coroutineVersion = "1.3.7"
+    val coroutineVersion = "1.3.8"
     implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:$coroutineVersion")
     implementation("org.jetbrains.kotlinx:kotlinx-coroutines-jdk8:$coroutineVersion")
     testImplementation("org.jetbrains.kotlinx:kotlinx-coroutines-test:$coroutineVersion")
 
-    val awsVersion = "2.13.23"
+    val awsVersion = "[2.13,2.14["
     implementation("software.amazon.awssdk:s3:$awsVersion")
     testImplementation("software.amazon.awssdk:sts:$awsVersion")
 
diff --git a/src/main/kotlin/com/lapanthere/signals/S3InputStream.kt b/src/main/kotlin/com/lapanthere/signals/S3InputStream.kt
index f4ea701..7973fa3 100644
--- a/src/main/kotlin/com/lapanthere/signals/S3InputStream.kt
+++ b/src/main/kotlin/com/lapanthere/signals/S3InputStream.kt
@@ -51,7 +51,8 @@ public class S3InputStream(
                     .bucket(bucket)
                     .key(key)
                     .range("bytes=$begin-$end")
-                    .build(), AsyncResponseTransformer.toBytes()
+                    .build(),
+                AsyncResponseTransformer.toBytes()
             ).await().asInputStream()
         }
     }.toMutableList()
diff --git a/src/main/kotlin/com/lapanthere/signals/S3OutputStream.kt b/src/main/kotlin/com/lapanthere/signals/S3OutputStream.kt
index e1a5e16..b85c345 100644
--- a/src/main/kotlin/com/lapanthere/signals/S3OutputStream.kt
+++ b/src/main/kotlin/com/lapanthere/signals/S3OutputStream.kt
@@ -69,23 +69,26 @@ public class S3OutputStream(
         semaphore.acquire()
         partSize.next()
         val part = Part(uploadID, parts.size + 1, digest, buffer)
-        parts.add(scope.async(CoroutineName("part-${part.partNumber}")) {
-            val response = s3.uploadPart(
-                UploadPartRequest.builder()
-                    .bucket(bucket)
-                    .key(key)
-                    .partNumber(part.partNumber)
-                    .uploadId(uploadID)
-                    .contentMD5(part.contentMD5)
-                    .contentLength(part.buffer.size.toLong())
-                    .build(), AsyncRequestBody.fromBytes(part.buffer)
-            ).await()
-            if (response.eTag != part.eTag) {
-                throw IOException("mismatching checksum: ${response.eTag} != ${part.eTag}")
+        parts.add(
+            scope.async(CoroutineName("part-${part.partNumber}")) {
+                val response = s3.uploadPart(
+                    UploadPartRequest.builder()
+                        .bucket(bucket)
+                        .key(key)
+                        .partNumber(part.partNumber)
+                        .uploadId(uploadID)
+                        .contentMD5(part.contentMD5)
+                        .contentLength(part.buffer.size.toLong())
+                        .build(),
+                    AsyncRequestBody.fromBytes(part.buffer)
+                ).await()
+                if (response.eTag != part.eTag) {
+                    throw IOException("mismatching checksum: ${response.eTag} != ${part.eTag}")
+                }
+                semaphore.release()
+                part.toCompletedPart()
             }
-            semaphore.release()
-            part.toCompletedPart()
-        })
+        )
         buffer.reset()
     }
 
diff --git a/src/test/kotlin/com/lapanthere/signals/S3InputStreamTest.kt b/src/test/kotlin/com/lapanthere/signals/S3InputStreamTest.kt
index 5dcdb1b..5c67596 100644
--- a/src/test/kotlin/com/lapanthere/signals/S3InputStreamTest.kt
+++ b/src/test/kotlin/com/lapanthere/signals/S3InputStreamTest.kt
@@ -38,7 +38,8 @@ class S3InputStreamTest {
                     .bucket(bucket)
                     .key(key)
                     .range("bytes=0-5242879")
-                    .build(), any<ByteArrayAsyncResponseTransformer<GetObjectResponse>>()
+                    .build(),
+                any<ByteArrayAsyncResponseTransformer<GetObjectResponse>>()
             )
         } returns CompletableFuture.completedFuture(
             ResponseBytes.fromByteArray(GetObjectResponse.builder().build(), ByteArray(32))
@@ -49,7 +50,8 @@ class S3InputStreamTest {
                     .bucket(bucket)
                     .key(key)
                     .range("bytes=5242880-10489185")
-                    .build(), any<ByteArrayAsyncResponseTransformer<GetObjectResponse>>()
+                    .build(),
+                any<ByteArrayAsyncResponseTransformer<GetObjectResponse>>()
             )
         } returns CompletableFuture.completedFuture(
             ResponseBytes.fromByteArray(GetObjectResponse.builder().build(), ByteArray(32))
@@ -77,7 +79,8 @@ class S3InputStreamTest {
                     .bucket(bucket)
                     .key(key)
                     .range("bytes=0-5242879")
-                    .build(), any<ByteArrayAsyncResponseTransformer<GetObjectResponse>>()
+                    .build(),
+                any<ByteArrayAsyncResponseTransformer<GetObjectResponse>>()
             )
         }
         verify(exactly = 1) {
@@ -86,7 +89,8 @@ class S3InputStreamTest {
                     .bucket(bucket)
                     .key(key)
                     .range("bytes=5242880-10489185")
-                    .build(), any<ByteArrayAsyncResponseTransformer<GetObjectResponse>>()
+                    .build(),
+                any<ByteArrayAsyncResponseTransformer<GetObjectResponse>>()
             )
         }
     }
@@ -99,7 +103,8 @@ class S3InputStreamTest {
                     .bucket(bucket)
                     .key(key)
                     .range("bytes=0-5242879")
-                    .build(), any<ByteArrayAsyncResponseTransformer<GetObjectResponse>>()
+                    .build(),
+                any<ByteArrayAsyncResponseTransformer<GetObjectResponse>>()
             )
         } throws SdkClientException.create("read timeout")
 
diff --git a/src/test/kotlin/com/lapanthere/signals/S3OutputStreamTest.kt b/src/test/kotlin/com/lapanthere/signals/S3OutputStreamTest.kt
index 384d6e2..15081bd 100644
--- a/src/test/kotlin/com/lapanthere/signals/S3OutputStreamTest.kt
+++ b/src/test/kotlin/com/lapanthere/signals/S3OutputStreamTest.kt
@@ -48,7 +48,8 @@ class S3OutputStreamTest {
                     .contentLength(32)
                     .contentMD5("cLyPS3KoaSFGi/joRB3OUQ==")
                     .partNumber(1)
-                    .build(), any<AsyncRequestBody>()
+                    .build(),
+                any<AsyncRequestBody>()
             )
         } returns CompletableFuture.completedFuture(
             UploadPartResponse.builder()
@@ -103,29 +104,40 @@ class S3OutputStreamTest {
         }
 
         verify {
-            s3.createMultipartUpload(CreateMultipartUploadRequest.builder()
-                .bucket(bucket)
-                .key(key)
-                .build())
-            s3.uploadPart(UploadPartRequest.builder()
-                .bucket(bucket)
-                .key(key)
-                .contentLength(32)
-                .contentMD5("cLyPS3KoaSFGi/joRB3OUQ==")
-                .partNumber(1)
-                .uploadId(uploadID)
-                .build(), any<AsyncRequestBody>())
-            s3.completeMultipartUpload(CompleteMultipartUploadRequest.builder()
-                .bucket(bucket)
-                .key(key)
-                .uploadId(uploadID)
-                .multipartUpload(CompletedMultipartUpload.builder()
-                    .parts(CompletedPart.builder()
-                        .eTag("70bc8f4b72a86921468bf8e8441dce51")
-                        .partNumber(1)
-                        .build())
-                    .build())
-                .build())
+            s3.createMultipartUpload(
+                CreateMultipartUploadRequest.builder()
+                    .bucket(bucket)
+                    .key(key)
+                    .build()
+            )
+            s3.uploadPart(
+                UploadPartRequest.builder()
+                    .bucket(bucket)
+                    .key(key)
+                    .contentLength(32)
+                    .contentMD5("cLyPS3KoaSFGi/joRB3OUQ==")
+                    .partNumber(1)
+                    .uploadId(uploadID)
+                    .build(),
+                any<AsyncRequestBody>()
+            )
+            s3.completeMultipartUpload(
+                CompleteMultipartUploadRequest.builder()
+                    .bucket(bucket)
+                    .key(key)
+                    .uploadId(uploadID)
+                    .multipartUpload(
+                        CompletedMultipartUpload.builder()
+                            .parts(
+                                CompletedPart.builder()
+                                    .eTag("70bc8f4b72a86921468bf8e8441dce51")
+                                    .partNumber(1)
+                                    .build()
+                            )
+                            .build()
+                    )
+                    .build()
+            )
         }
 
         verify(exactly = 0) {
@@ -152,7 +164,8 @@ class S3OutputStreamTest {
                     .contentLength(32)
                     .contentMD5("cLyPS3KoaSFGi/joRB3OUQ==")
                     .partNumber(1)
-                    .build(), any<AsyncRequestBody>()
+                    .build(),
+                any<AsyncRequestBody>()
             )
         } throws SdkClientException.create("write timeout")
 
@@ -165,18 +178,23 @@ class S3OutputStreamTest {
         }
 
         verify {
-            s3.createMultipartUpload(CreateMultipartUploadRequest.builder()
-                .bucket(bucket)
-                .key(key)
-                .build())
-            s3.uploadPart(UploadPartRequest.builder()
-                .bucket(bucket)
-                .key(key)
-                .contentLength(32)
-                .contentMD5("cLyPS3KoaSFGi/joRB3OUQ==")
-                .partNumber(1)
-                .uploadId(uploadID)
-                .build(), any<AsyncRequestBody>())
+            s3.createMultipartUpload(
+                CreateMultipartUploadRequest.builder()
+                    .bucket(bucket)
+                    .key(key)
+                    .build()
+            )
+            s3.uploadPart(
+                UploadPartRequest.builder()
+                    .bucket(bucket)
+                    .key(key)
+                    .contentLength(32)
+                    .contentMD5("cLyPS3KoaSFGi/joRB3OUQ==")
+                    .partNumber(1)
+                    .uploadId(uploadID)
+                    .build(),
+                any<AsyncRequestBody>()
+            )
         }
 
         verify(exactly = 1) {