diff --git a/fuel-kotlinx-serialization/src/appleMain/kotlin/fuel/serialization/ResponseExtensions.kt b/fuel-kotlinx-serialization/src/appleMain/kotlin/fuel/serialization/ResponseExtensions.kt
index ccaec345..389bf715 100644
--- a/fuel-kotlinx-serialization/src/appleMain/kotlin/fuel/serialization/ResponseExtensions.kt
+++ b/fuel-kotlinx-serialization/src/appleMain/kotlin/fuel/serialization/ResponseExtensions.kt
@@ -6,8 +6,8 @@ import fuel.HttpResponse
 import kotlinx.serialization.DeserializationStrategy
 import kotlinx.serialization.json.Json
 
-public fun <T : Any> HttpResponse.toJson(
-    json: Json = Json { allowStructuredMapKeys = true },
+public actual fun <T : Any> HttpResponse.toJson(
+    json: Json,
     deserializationStrategy: DeserializationStrategy<T>
 ): Result<T?, Throwable> = runCatching {
     body?.let { json.decodeFromString(deserializationStrategy, it) }
diff --git a/fuel-kotlinx-serialization/src/commonMain/kotlin/fuel/serialization/ResponseExtensions.kt b/fuel-kotlinx-serialization/src/commonMain/kotlin/fuel/serialization/ResponseExtensions.kt
new file mode 100644
index 00000000..e0dd4dcd
--- /dev/null
+++ b/fuel-kotlinx-serialization/src/commonMain/kotlin/fuel/serialization/ResponseExtensions.kt
@@ -0,0 +1,11 @@
+package fuel.serialization
+
+import com.github.kittinunf.result.Result
+import fuel.HttpResponse
+import kotlinx.serialization.DeserializationStrategy
+import kotlinx.serialization.json.Json
+
+public expect fun <T : Any> HttpResponse.toJson(
+    json: Json = Json,
+    deserializationStrategy: DeserializationStrategy<T>
+): Result<T?, Throwable>
diff --git a/fuel-kotlinx-serialization/src/jsMain/kotlin/fuel/serialization/ResponseExtensions.kt b/fuel-kotlinx-serialization/src/jsMain/kotlin/fuel/serialization/ResponseExtensions.kt
index 90bcc2e2..f519db16 100644
--- a/fuel-kotlinx-serialization/src/jsMain/kotlin/fuel/serialization/ResponseExtensions.kt
+++ b/fuel-kotlinx-serialization/src/jsMain/kotlin/fuel/serialization/ResponseExtensions.kt
@@ -6,8 +6,8 @@ import fuel.HttpResponse
 import kotlinx.serialization.DeserializationStrategy
 import kotlinx.serialization.json.Json
 
-public fun <T : Any> HttpResponse.toJson(
-    json: Json = Json { allowStructuredMapKeys = true },
+public actual fun <T : Any> HttpResponse.toJson(
+    json: Json,
     deserializationStrategy: DeserializationStrategy<T>
 ): Result<T?, Throwable> = runCatching {
     json.decodeFromString(deserializationStrategy, response?.json().toString())
diff --git a/fuel-kotlinx-serialization/src/jvmMain/kotlin/fuel/serialization/ResponseExtensions.kt b/fuel-kotlinx-serialization/src/jvmMain/kotlin/fuel/serialization/ResponseExtensions.kt
index 885c0946..ae27ac69 100644
--- a/fuel-kotlinx-serialization/src/jvmMain/kotlin/fuel/serialization/ResponseExtensions.kt
+++ b/fuel-kotlinx-serialization/src/jvmMain/kotlin/fuel/serialization/ResponseExtensions.kt
@@ -6,8 +6,8 @@ import fuel.HttpResponse
 import kotlinx.serialization.DeserializationStrategy
 import kotlinx.serialization.json.Json
 
-public fun <T : Any> HttpResponse.toJson(
-    json: Json = Json { allowStructuredMapKeys = true },
+public actual fun <T : Any> HttpResponse.toJson(
+    json: Json,
     deserializationStrategy: DeserializationStrategy<T>
 ): Result<T?, Throwable> = runCatching {
     json.decodeFromString(deserializationStrategy, body.string())