diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index d33d2a1d..f8e0763a 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -98,8 +98,8 @@ jobs:
 
       - uses: gradle/actions/setup-gradle@v5
 
-      - name: Run WasmJs browser tests
-        run: ./gradlew wasmJsBrowserTest
+      - name: Run WasmJs tests
+        run: ./gradlew wasmJsBrowserTest wasmJsNodeTest
 
       - name: Upload test results
         if: always()
diff --git a/examples/app/src/commonMain/kotlin/com/linroid/kdown/examples/App.kt b/examples/app/src/commonMain/kotlin/com/linroid/kdown/examples/App.kt
index b35fd32e..731aefdd 100644
--- a/examples/app/src/commonMain/kotlin/com/linroid/kdown/examples/App.kt
+++ b/examples/app/src/commonMain/kotlin/com/linroid/kdown/examples/App.kt
@@ -211,7 +211,7 @@ fun App() {
             scope = scope,
             kdown = kdown,
             url = url,
-            directory = Path("downloads"),
+            directory = "downloads",
             fileName = fileName.ifBlank { null },
             speedLimit = speedLimit,
             priority = priority,
@@ -879,7 +879,7 @@ private fun startDownload(
   scope: CoroutineScope,
   kdown: KDownApi,
   url: String,
-  directory: Path,
+  directory: String,
   fileName: String?,
   speedLimit: SpeedLimit = SpeedLimit.Unlimited,
   priority: DownloadPriority = DownloadPriority.NORMAL,
diff --git a/library/api/build.gradle.kts b/library/api/build.gradle.kts
index 2b0f76de..7865964d 100644
--- a/library/api/build.gradle.kts
+++ b/library/api/build.gradle.kts
@@ -28,7 +28,6 @@ kotlin {
     commonMain.dependencies {
       implementation(libs.kotlinx.coroutines.core)
       implementation(libs.kotlinx.serialization.json)
-      api(libs.kotlinx.io.core)
       implementation(libs.kotlinx.datetime)
     }
     commonTest.dependencies {
diff --git a/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadRequest.kt b/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadRequest.kt
index 35debf0c..ac3a0413 100644
--- a/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadRequest.kt
+++ b/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadRequest.kt
@@ -1,6 +1,5 @@
 package com.linroid.kdown.api
 
-import kotlinx.io.files.Path
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.Transient
 
@@ -9,6 +8,7 @@ import kotlinx.serialization.Transient
  *
  * @property url the HTTP(S) URL to download from. Must not be blank.
  * @property directory the local directory where the file will be saved.
+ *   When `null`, the implementation chooses a default location.
  * @property fileName explicit file name to save as. When `null`, the
  *   file name is determined from the server response
  *   (Content-Disposition header, URL path, or a fallback).
@@ -33,8 +33,7 @@ import kotlinx.serialization.Transient
 @Serializable
 data class DownloadRequest(
   val url: String,
-  @Serializable(with = PathSerializer::class)
-  val directory: Path,
+  val directory: String? = null,
   val fileName: String? = null,
   val connections: Int = 1,
   val headers: Map<String, String> = emptyMap(),
diff --git a/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadState.kt b/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadState.kt
index 93e59e84..bb22ee3a 100644
--- a/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadState.kt
+++ b/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadState.kt
@@ -1,7 +1,5 @@
 package com.linroid.kdown.api
 
-import kotlinx.io.files.Path
-
 sealed class DownloadState {
   data object Idle : DownloadState()
   data class Scheduled(val schedule: DownloadSchedule) : DownloadState()
@@ -9,7 +7,7 @@ sealed class DownloadState {
   data object Pending : DownloadState()
   data class Downloading(val progress: DownloadProgress) : DownloadState()
   data class Paused(val progress: DownloadProgress) : DownloadState()
-  data class Completed(val filePath: Path) : DownloadState()
+  data class Completed(val filePath: String) : DownloadState()
   data class Failed(val error: KDownError) : DownloadState()
   data object Canceled : DownloadState()
 
diff --git a/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadTask.kt b/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadTask.kt
index cbcacba9..3e76fe98 100644
--- a/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadTask.kt
+++ b/library/api/src/commonMain/kotlin/com/linroid/kdown/api/DownloadTask.kt
@@ -2,7 +2,6 @@ package com.linroid.kdown.api
 
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.first
-import kotlinx.io.files.Path
 import kotlin.time.Instant
 
 /**
@@ -60,13 +59,13 @@ interface DownloadTask {
    */
   suspend fun remove()
 
-  suspend fun await(): Result<Path>
+  suspend fun await(): Result<String>
 }
 
 /**
  * Default [await] implementation for [DownloadTask].
  */
-suspend fun DownloadTask.awaitDefault(): Result<Path> {
+suspend fun DownloadTask.awaitDefault(): Result<String> {
   val finalState = state.first { it.isTerminal }
   return when (finalState) {
     is DownloadState.Completed -> Result.success(finalState.filePath)
diff --git a/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadPriorityTest.kt b/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadPriorityTest.kt
index dca606f0..50c2a334 100644
--- a/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadPriorityTest.kt
+++ b/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadPriorityTest.kt
@@ -51,7 +51,7 @@ class DownloadPriorityTest {
   fun defaultPriority_inRequest_isNormal() {
     val request = DownloadRequest(
       url = "https://example.com/file.zip",
-      directory = kotlinx.io.files.Path("/tmp")
+      directory = "/tmp"
     )
     assertEquals(DownloadPriority.NORMAL, request.priority)
   }
@@ -60,7 +60,7 @@ class DownloadPriorityTest {
   fun customPriority_inRequest_isPreserved() {
     val request = DownloadRequest(
       url = "https://example.com/file.zip",
-      directory = kotlinx.io.files.Path("/tmp"),
+      directory = "/tmp",
       priority = DownloadPriority.URGENT
     )
     assertEquals(DownloadPriority.URGENT, request.priority)
diff --git a/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadRequestTest.kt b/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadRequestTest.kt
index 9079df6f..4f6bc18c 100644
--- a/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadRequestTest.kt
+++ b/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadRequestTest.kt
@@ -1,6 +1,5 @@
 package com.linroid.kdown.api
 
-import kotlinx.io.files.Path
 import kotlinx.serialization.json.Json
 import kotlin.test.Test
 import kotlin.test.assertEquals
@@ -15,7 +14,7 @@ class DownloadRequestTest {
   fun defaultConnections_isOne() {
     val request = DownloadRequest(
       url = "https://example.com/file",
-      directory = Path("/tmp")
+      directory = "/tmp"
     )
     assertEquals(1, request.connections)
   }
@@ -24,7 +23,7 @@ class DownloadRequestTest {
   fun defaultFileName_isNull() {
     val request = DownloadRequest(
       url = "https://example.com/file",
-      directory = Path("/tmp")
+      directory = "/tmp"
     )
     assertNull(request.fileName)
   }
@@ -33,7 +32,7 @@ class DownloadRequestTest {
   fun customFileName_preserved() {
     val request = DownloadRequest(
       url = "https://example.com/file",
-      directory = Path("/tmp"),
+      directory = "/tmp",
       fileName = "custom.zip"
     )
     assertEquals("custom.zip", request.fileName)
@@ -42,10 +41,10 @@ class DownloadRequestTest {
   @Test
   fun blankUrl_throws() {
     assertFailsWith<IllegalArgumentException> {
-      DownloadRequest(url = "", directory = Path("/tmp"))
+      DownloadRequest(url = "", directory = "/tmp")
     }
     assertFailsWith<IllegalArgumentException> {
-      DownloadRequest(url = "   ", directory = Path("/tmp"))
+      DownloadRequest(url = "   ", directory = "/tmp")
     }
   }
 
@@ -54,7 +53,7 @@ class DownloadRequestTest {
     assertFailsWith<IllegalArgumentException> {
       DownloadRequest(
         url = "https://example.com/file",
-        directory = Path("/tmp"),
+        directory = "/tmp",
         connections = 0
       )
     }
@@ -65,7 +64,7 @@ class DownloadRequestTest {
     assertFailsWith<IllegalArgumentException> {
       DownloadRequest(
         url = "https://example.com/file",
-        directory = Path("/tmp"),
+        directory = "/tmp",
         connections = -1
       )
     }
@@ -75,7 +74,7 @@ class DownloadRequestTest {
   fun defaultHeaders_isEmpty() {
     val request = DownloadRequest(
       url = "https://example.com/file",
-      directory = Path("/tmp")
+      directory = "/tmp"
     )
     assertEquals(emptyMap(), request.headers)
   }
@@ -88,7 +87,7 @@ class DownloadRequestTest {
     )
     val request = DownloadRequest(
       url = "https://example.com/file",
-      directory = Path("/tmp"),
+      directory = "/tmp",
       headers = headers
     )
     assertEquals(headers, request.headers)
@@ -100,7 +99,7 @@ class DownloadRequestTest {
   fun defaultSpeedLimit_isUnlimited() {
     val request = DownloadRequest(
       url = "https://example.com/file",
-      directory = Path("/tmp")
+      directory = "/tmp"
     )
     assertTrue(request.speedLimit.isUnlimited)
   }
@@ -110,7 +109,7 @@ class DownloadRequestTest {
     val limit = SpeedLimit.mbps(10)
     val request = DownloadRequest(
       url = "https://example.com/file",
-      directory = Path("/tmp"),
+      directory = "/tmp",
       speedLimit = limit
     )
     assertEquals(limit, request.speedLimit)
@@ -122,7 +121,7 @@ class DownloadRequestTest {
     val json = Json { ignoreUnknownKeys = true }
     val request = DownloadRequest(
       url = "https://example.com/file",
-      directory = Path("/tmp"),
+      directory = "/tmp",
       speedLimit = SpeedLimit.kbps(512)
     )
     val serialized = json.encodeToString(
@@ -143,7 +142,7 @@ class DownloadRequestTest {
     val json = Json { ignoreUnknownKeys = true }
     val request = DownloadRequest(
       url = "https://example.com/file",
-      directory = Path("/tmp")
+      directory = "/tmp"
     )
     val serialized = json.encodeToString(
       DownloadRequest.serializer(), request
@@ -153,4 +152,12 @@ class DownloadRequestTest {
     )
     assertTrue(deserialized.speedLimit.isUnlimited)
   }
+
+  @Test
+  fun defaultDirectory_isNull() {
+    val request = DownloadRequest(
+      url = "https://example.com/file"
+    )
+    assertNull(request.directory)
+  }
 }
diff --git a/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadScheduleTest.kt b/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadScheduleTest.kt
index a970282a..c42d8cff 100644
--- a/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadScheduleTest.kt
+++ b/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadScheduleTest.kt
@@ -1,6 +1,5 @@
 package com.linroid.kdown.api
 
-import kotlinx.io.files.Path
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertIs
@@ -16,7 +15,7 @@ class DownloadScheduleTest {
   fun immediate_isDefaultSchedule() {
     val request = DownloadRequest(
       url = "https://example.com/file.zip",
-      directory = Path("/tmp")
+      directory = "/tmp"
     )
     assertEquals(DownloadSchedule.Immediate, request.schedule)
   }
diff --git a/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadStateTest.kt b/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadStateTest.kt
index 498d1672..4b1fb6b3 100644
--- a/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadStateTest.kt
+++ b/library/api/src/commonTest/kotlin/com/linroid/kdown/api/DownloadStateTest.kt
@@ -1,6 +1,5 @@
 package com.linroid.kdown.api
 
-import kotlinx.io.files.Path
 import kotlin.test.Test
 import kotlin.test.assertFalse
 import kotlin.test.assertTrue
@@ -73,12 +72,12 @@ class DownloadStateTest {
 
   @Test
   fun completed_isTerminal() {
-    assertTrue(DownloadState.Completed(Path("/path/file")).isTerminal)
+    assertTrue(DownloadState.Completed("/path/file").isTerminal)
   }
 
   @Test
   fun completed_isNotActive() {
-    assertFalse(DownloadState.Completed(Path("/path/file")).isActive)
+    assertFalse(DownloadState.Completed("/path/file").isActive)
   }
 
   @Test
diff --git a/library/core/build.gradle.kts b/library/core/build.gradle.kts
index 3a54a343..7024167c 100644
--- a/library/core/build.gradle.kts
+++ b/library/core/build.gradle.kts
@@ -30,12 +30,7 @@ kotlin {
 
   @OptIn(ExperimentalWasmDsl::class)
   wasmJs {
-    browser {
-      testTask {
-        // kotlinx.io.files.Path requires Node.js APIs unavailable in browser tests
-        enabled = false
-      }
-    }
+    nodejs()
   }
 
   sourceSets {
@@ -44,6 +39,7 @@ kotlin {
       implementation(libs.kotlinx.coroutines.core)
       implementation(libs.kotlinx.serialization.json)
       implementation(libs.kotlinx.datetime)
+      implementation(libs.kotlinx.io.core)
     }
     commonTest.dependencies {
       implementation(libs.kotlin.test)
diff --git a/library/core/src/commonMain/kotlin/com/linroid/kdown/core/KDown.kt b/library/core/src/commonMain/kotlin/com/linroid/kdown/core/KDown.kt
index 815c7b5e..ebbe9700 100644
--- a/library/core/src/commonMain/kotlin/com/linroid/kdown/core/KDown.kt
+++ b/library/core/src/commonMain/kotlin/com/linroid/kdown/core/KDown.kt
@@ -409,7 +409,7 @@ class KDown(
       )
 
       TaskState.COMPLETED -> DownloadState.Completed(
-        record.destPath
+        record.destPath.toString()
       )
 
       TaskState.FAILED -> DownloadState.Failed(
diff --git a/library/core/src/commonMain/kotlin/com/linroid/kdown/core/engine/DownloadCoordinator.kt b/library/core/src/commonMain/kotlin/com/linroid/kdown/core/engine/DownloadCoordinator.kt
index 8c4a965d..63b0e43e 100644
--- a/library/core/src/commonMain/kotlin/com/linroid/kdown/core/engine/DownloadCoordinator.kt
+++ b/library/core/src/commonMain/kotlin/com/linroid/kdown/core/engine/DownloadCoordinator.kt
@@ -55,9 +55,11 @@ internal class DownloadCoordinator(
     stateFlow: MutableStateFlow<DownloadState>,
     segmentsFlow: MutableStateFlow<List<Segment>>
   ) {
+    val directory = request.directory?.let { Path(it) }
+      ?: error("directory is required for download")
     val initialDestPath = request.fileName?.let {
-      Path(request.directory, it)
-    } ?: request.directory
+      Path(directory, it)
+    } ?: directory
 
     val now = Clock.System.now()
     taskStore.save(
@@ -186,7 +188,9 @@ internal class DownloadCoordinator(
 
     val fileName = sourceInfo.suggestedFileName
       ?: fileNameResolver.resolve(request, toServerInfo(sourceInfo))
-    val destPath = deduplicatePath(request.directory, fileName)
+    val dir = request.directory?.let { Path(it) }
+      ?: error("directory is required for download")
+    val destPath = deduplicatePath(dir, fileName)
 
     val now = Clock.System.now()
     updateTaskRecord(taskId) {
@@ -249,7 +253,8 @@ internal class DownloadCoordinator(
       KDownLogger.i("Coordinator") {
         "Download completed successfully for taskId=$taskId"
       }
-      stateFlow.value = DownloadState.Completed(destPath)
+      stateFlow.value =
+        DownloadState.Completed(destPath.toString())
     } finally {
       fileAccessor.close()
       withContext(NonCancellable) {
@@ -440,7 +445,8 @@ internal class DownloadCoordinator(
         )
       }
 
-      stateFlow.value = DownloadState.Completed(taskRecord.destPath)
+      stateFlow.value =
+        DownloadState.Completed(taskRecord.destPath.toString())
     } finally {
       fileAccessor.close()
       withContext(NonCancellable) {
diff --git a/library/api/src/commonMain/kotlin/com/linroid/kdown/api/PathSerializer.kt b/library/core/src/commonMain/kotlin/com/linroid/kdown/core/file/PathSerializer.kt
similarity index 77%
rename from library/api/src/commonMain/kotlin/com/linroid/kdown/api/PathSerializer.kt
rename to library/core/src/commonMain/kotlin/com/linroid/kdown/core/file/PathSerializer.kt
index 9b61eeaf..d307b068 100644
--- a/library/api/src/commonMain/kotlin/com/linroid/kdown/api/PathSerializer.kt
+++ b/library/core/src/commonMain/kotlin/com/linroid/kdown/core/file/PathSerializer.kt
@@ -1,4 +1,4 @@
-package com.linroid.kdown.api
+package com.linroid.kdown.core.file
 
 import kotlinx.io.files.Path
 import kotlinx.serialization.KSerializer
@@ -8,9 +8,11 @@ import kotlinx.serialization.descriptors.SerialDescriptor
 import kotlinx.serialization.encoding.Decoder
 import kotlinx.serialization.encoding.Encoder
 
-object PathSerializer : KSerializer<Path> {
+internal object PathSerializer : KSerializer<Path> {
   override val descriptor: SerialDescriptor =
-    PrimitiveSerialDescriptor("kotlinx.io.files.Path", PrimitiveKind.STRING)
+    PrimitiveSerialDescriptor(
+      "kotlinx.io.files.Path", PrimitiveKind.STRING
+    )
 
   override fun serialize(encoder: Encoder, value: Path) {
     encoder.encodeString(value.toString())
diff --git a/library/core/src/commonMain/kotlin/com/linroid/kdown/core/task/DownloadTaskImpl.kt b/library/core/src/commonMain/kotlin/com/linroid/kdown/core/task/DownloadTaskImpl.kt
index 95ceb8ee..d260acc9 100644
--- a/library/core/src/commonMain/kotlin/com/linroid/kdown/core/task/DownloadTaskImpl.kt
+++ b/library/core/src/commonMain/kotlin/com/linroid/kdown/core/task/DownloadTaskImpl.kt
@@ -11,7 +11,6 @@ import com.linroid.kdown.api.Segment
 import com.linroid.kdown.api.DownloadTask
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.first
-import kotlinx.io.files.Path
 import kotlin.time.Instant
 
 internal class DownloadTaskImpl(
@@ -60,7 +59,7 @@ internal class DownloadTaskImpl(
     removeAction()
   }
 
-  override suspend fun await(): Result<Path> {
+  override suspend fun await(): Result<String> {
     val finalState = state.first { it.isTerminal }
     return when (finalState) {
       is DownloadState.Completed -> Result.success(finalState.filePath)
diff --git a/library/core/src/commonMain/kotlin/com/linroid/kdown/core/task/TaskRecord.kt b/library/core/src/commonMain/kotlin/com/linroid/kdown/core/task/TaskRecord.kt
index 381c270b..369403c0 100644
--- a/library/core/src/commonMain/kotlin/com/linroid/kdown/core/task/TaskRecord.kt
+++ b/library/core/src/commonMain/kotlin/com/linroid/kdown/core/task/TaskRecord.kt
@@ -2,7 +2,7 @@ package com.linroid.kdown.core.task
 
 import com.linroid.kdown.api.DownloadRequest
 import com.linroid.kdown.core.engine.SourceResumeState
-import com.linroid.kdown.api.PathSerializer
+import com.linroid.kdown.core.file.PathSerializer
 import com.linroid.kdown.api.Segment
 import kotlinx.io.files.Path
 import kotlinx.serialization.Serializable
diff --git a/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/DownloadQueueTest.kt b/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/DownloadQueueTest.kt
index 462cd530..f81d30fe 100644
--- a/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/DownloadQueueTest.kt
+++ b/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/DownloadQueueTest.kt
@@ -22,7 +22,6 @@ import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.test.runTest
 import kotlinx.coroutines.withContext
 import kotlinx.coroutines.withTimeout
-import kotlinx.io.files.Path
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertIs
@@ -41,7 +40,7 @@ class DownloadQueueTest {
     priority: DownloadPriority = DownloadPriority.NORMAL
   ) = DownloadRequest(
     url = url,
-    directory = Path("/tmp"),
+    directory = "/tmp",
     priority = priority
   )
 
diff --git a/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/DownloadSchedulerTest.kt b/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/DownloadSchedulerTest.kt
index 11fbfe27..f978bb18 100644
--- a/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/DownloadSchedulerTest.kt
+++ b/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/DownloadSchedulerTest.kt
@@ -22,7 +22,6 @@ import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.test.runTest
 import kotlinx.coroutines.withContext
 import kotlinx.coroutines.withTimeout
-import kotlinx.io.files.Path
 import kotlin.test.Test
 import kotlin.test.assertIs
 import kotlin.test.assertTrue
@@ -35,7 +34,7 @@ class DownloadSchedulerTest {
     priority: DownloadPriority = DownloadPriority.NORMAL
   ) = DownloadRequest(
     url = "https://example.com/file.zip",
-    directory = Path("/tmp"),
+    directory = "/tmp",
     priority = priority
   )
 
diff --git a/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/ScheduleManagerTest.kt b/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/ScheduleManagerTest.kt
index f72ffe76..1222c383 100644
--- a/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/ScheduleManagerTest.kt
+++ b/library/core/src/commonTest/kotlin/com/linroid/kdown/engine/ScheduleManagerTest.kt
@@ -26,7 +26,6 @@ import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.test.runTest
 import kotlinx.coroutines.withContext
 import kotlinx.coroutines.withTimeout
-import kotlinx.io.files.Path
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
@@ -43,7 +42,7 @@ class ScheduleManagerTest {
     conditions: List<DownloadCondition> = emptyList()
   ) = DownloadRequest(
     url = "https://example.com/file.zip",
-    directory = Path("/tmp"),
+    directory = "/tmp",
     schedule = schedule,
     conditions = conditions,
     priority = DownloadPriority.NORMAL
diff --git a/library/core/src/commonTest/kotlin/com/linroid/kdown/file/DefaultFileNameResolverTest.kt b/library/core/src/commonTest/kotlin/com/linroid/kdown/file/DefaultFileNameResolverTest.kt
index 3aff14ac..ffc2ebb0 100644
--- a/library/core/src/commonTest/kotlin/com/linroid/kdown/file/DefaultFileNameResolverTest.kt
+++ b/library/core/src/commonTest/kotlin/com/linroid/kdown/file/DefaultFileNameResolverTest.kt
@@ -3,14 +3,13 @@ package com.linroid.kdown.file
 import com.linroid.kdown.api.DownloadRequest
 import com.linroid.kdown.core.engine.ServerInfo
 import com.linroid.kdown.core.file.DefaultFileNameResolver
-import kotlinx.io.files.Path
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
 class DefaultFileNameResolverTest {
 
   private val resolver = DefaultFileNameResolver()
-  private val dir = Path("/tmp")
+  private val dir = "/tmp"
 
   private fun serverInfo(contentDisposition: String? = null) = ServerInfo(
     contentLength = 1000,
diff --git a/library/core/src/commonTest/kotlin/com/linroid/kdown/task/InMemoryTaskStoreTest.kt b/library/core/src/commonTest/kotlin/com/linroid/kdown/task/InMemoryTaskStoreTest.kt
index 9f2aad8a..2fd640bc 100644
--- a/library/core/src/commonTest/kotlin/com/linroid/kdown/task/InMemoryTaskStoreTest.kt
+++ b/library/core/src/commonTest/kotlin/com/linroid/kdown/task/InMemoryTaskStoreTest.kt
@@ -7,10 +7,10 @@ import com.linroid.kdown.core.task.TaskState
 import kotlinx.coroutines.test.runTest
 import kotlinx.io.files.Path
 import kotlin.test.Test
-import kotlin.time.Instant
 import kotlin.test.assertEquals
 import kotlin.test.assertNull
 import kotlin.test.assertTrue
+import kotlin.time.Instant
 
 class InMemoryTaskStoreTest {
 
@@ -21,7 +21,7 @@ class InMemoryTaskStoreTest {
     taskId = taskId,
     request = DownloadRequest(
       url = "https://example.com/file.bin",
-      directory = Path("/tmp"),
+      directory = "/tmp",
       connections = 4,
       headers = mapOf("Authorization" to "Bearer token")
     ),
diff --git a/library/core/src/commonTest/kotlin/com/linroid/kdown/task/TaskRecordTest.kt b/library/core/src/commonTest/kotlin/com/linroid/kdown/task/TaskRecordTest.kt
index a3d53a8d..88e62843 100644
--- a/library/core/src/commonTest/kotlin/com/linroid/kdown/task/TaskRecordTest.kt
+++ b/library/core/src/commonTest/kotlin/com/linroid/kdown/task/TaskRecordTest.kt
@@ -22,7 +22,7 @@ class TaskRecordTest {
     headers: Map<String, String> = emptyMap()
   ) = DownloadRequest(
     url = url,
-    directory = Path("/tmp"),
+    directory = "/tmp",
     connections = connections,
     headers = headers
   )
diff --git a/library/remote/src/commonMain/kotlin/com/linroid/kdown/remote/RemoteDownloadTask.kt b/library/remote/src/commonMain/kotlin/com/linroid/kdown/remote/RemoteDownloadTask.kt
index 8dd26035..31a244fe 100644
--- a/library/remote/src/commonMain/kotlin/com/linroid/kdown/remote/RemoteDownloadTask.kt
+++ b/library/remote/src/commonMain/kotlin/com/linroid/kdown/remote/RemoteDownloadTask.kt
@@ -24,7 +24,6 @@ import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.flow.first
-import kotlinx.io.files.Path
 import kotlinx.serialization.json.Json
 import kotlin.time.Instant
 
@@ -127,7 +126,7 @@ internal class RemoteDownloadTask(
     )
   }
 
-  override suspend fun await(): Result<Path> {
+  override suspend fun await(): Result<String> {
     val finalState = state.first { it.isTerminal }
     return when (finalState) {
       is DownloadState.Completed ->
diff --git a/library/remote/src/commonMain/kotlin/com/linroid/kdown/remote/WireMapper.kt b/library/remote/src/commonMain/kotlin/com/linroid/kdown/remote/WireMapper.kt
index d4a8c167..1a020487 100644
--- a/library/remote/src/commonMain/kotlin/com/linroid/kdown/remote/WireMapper.kt
+++ b/library/remote/src/commonMain/kotlin/com/linroid/kdown/remote/WireMapper.kt
@@ -7,7 +7,6 @@ import com.linroid.kdown.api.DownloadState
 import com.linroid.kdown.api.KDownError
 import com.linroid.kdown.api.Segment
 import com.linroid.kdown.api.SpeedLimit
-import kotlinx.io.files.Path
 import kotlin.time.Instant
 
 internal object WireMapper {
@@ -15,7 +14,7 @@ internal object WireMapper {
   fun toDownloadRequest(wire: WireTaskResponse): DownloadRequest {
     return DownloadRequest(
       url = wire.url,
-      directory = Path(wire.directory),
+      directory = wire.directory,
       fileName = wire.fileName,
       connections = 1,
       speedLimit = if (wire.speedLimitBytesPerSecond > 0) {
@@ -30,7 +29,7 @@ internal object WireMapper {
   fun toCreateWire(request: DownloadRequest): WireCreateDownloadRequest {
     return WireCreateDownloadRequest(
       url = request.url,
-      directory = request.directory.toString(),
+      directory = request.directory ?: "",
       fileName = request.fileName,
       connections = request.connections,
       headers = request.headers,
@@ -69,7 +68,7 @@ internal object WireMapper {
           ?: DownloadProgress(0, 0)
       )
       "completed" -> DownloadState.Completed(
-        Path(filePath ?: "")
+        filePath ?: ""
       )
       "failed" -> DownloadState.Failed(
         KDownError.Unknown(cause = Exception(error ?: "Unknown"))
diff --git a/library/sqlite/build.gradle.kts b/library/sqlite/build.gradle.kts
index 8a8d59a2..49252c64 100644
--- a/library/sqlite/build.gradle.kts
+++ b/library/sqlite/build.gradle.kts
@@ -30,6 +30,7 @@ kotlin {
       implementation(libs.sqldelight.coroutines)
       implementation(libs.kotlinx.coroutines.core)
       implementation(libs.kotlinx.serialization.json)
+      implementation(libs.kotlinx.io.core)
     }
     androidMain.dependencies {
       implementation(libs.sqldelight.android.driver)
diff --git a/server/src/main/kotlin/com/linroid/kdown/server/TaskMapper.kt b/server/src/main/kotlin/com/linroid/kdown/server/TaskMapper.kt
index 3240d1a8..f25e0a1a 100644
--- a/server/src/main/kotlin/com/linroid/kdown/server/TaskMapper.kt
+++ b/server/src/main/kotlin/com/linroid/kdown/server/TaskMapper.kt
@@ -17,7 +17,7 @@ internal object TaskMapper {
     return TaskResponse(
       taskId = task.taskId,
       url = task.request.url,
-      directory = task.request.directory.toString(),
+      directory = task.request.directory ?: "",
       fileName = task.request.fileName,
       state = stateToString(state),
       progress = extractProgress(state)?.let(::toProgressResponse),
@@ -100,7 +100,7 @@ internal object TaskMapper {
 
   private fun extractFilePath(state: DownloadState): String? {
     return when (state) {
-      is DownloadState.Completed -> state.filePath.toString()
+      is DownloadState.Completed -> state.filePath
       else -> null
     }
   }
diff --git a/server/src/main/kotlin/com/linroid/kdown/server/api/DownloadRoutes.kt b/server/src/main/kotlin/com/linroid/kdown/server/api/DownloadRoutes.kt
index a6e84fe0..0d091fce 100644
--- a/server/src/main/kotlin/com/linroid/kdown/server/api/DownloadRoutes.kt
+++ b/server/src/main/kotlin/com/linroid/kdown/server/api/DownloadRoutes.kt
@@ -18,7 +18,6 @@ import io.ktor.server.routing.get
 import io.ktor.server.routing.post
 import io.ktor.server.routing.put
 import io.ktor.server.routing.route
-import kotlinx.io.files.Path
 
 /**
  * Installs the `/api/downloads` REST routes for managing tasks.
@@ -51,7 +50,7 @@ internal fun Route.downloadRoutes(kdown: KDownApi) {
       }
       val request = DownloadRequest(
         url = body.url,
-        directory = Path(body.directory),
+        directory = body.directory,
         fileName = body.fileName,
         connections = body.connections,
         headers = body.headers,
diff --git a/server/src/test/kotlin/com/linroid/kdown/server/TaskMapperTest.kt b/server/src/test/kotlin/com/linroid/kdown/server/TaskMapperTest.kt
index cac5a1a0..72ac0d94 100644
--- a/server/src/test/kotlin/com/linroid/kdown/server/TaskMapperTest.kt
+++ b/server/src/test/kotlin/com/linroid/kdown/server/TaskMapperTest.kt
@@ -5,7 +5,6 @@ import com.linroid.kdown.api.DownloadSchedule
 import com.linroid.kdown.api.DownloadState
 import com.linroid.kdown.api.KDownError
 import com.linroid.kdown.api.Segment
-import kotlinx.io.files.Path
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertNull
@@ -36,7 +35,7 @@ class TaskMapperTest {
       DownloadState.Paused(DownloadProgress(500, 1000))
     ))
     assertEquals("completed", TaskMapper.stateToString(
-      DownloadState.Completed(Path("/tmp/file.zip"))
+      DownloadState.Completed("/tmp/file.zip")
     ))
     assertEquals("failed", TaskMapper.stateToString(
       DownloadState.Failed(