diff --git a/core/runtime/src/commonMain/kotlin/com/kitakkun/backintime/core/runtime/internal/CaptureUtils.kt b/core/runtime/src/commonMain/kotlin/com/kitakkun/backintime/core/runtime/internal/CaptureUtils.kt
index 0a27557a..77b3eece 100644
--- a/core/runtime/src/commonMain/kotlin/com/kitakkun/backintime/core/runtime/internal/CaptureUtils.kt
+++ b/core/runtime/src/commonMain/kotlin/com/kitakkun/backintime/core/runtime/internal/CaptureUtils.kt
@@ -5,7 +5,7 @@ package com.kitakkun.backintime.core.runtime.internal
 import com.kitakkun.backintime.core.runtime.BackInTimeDebuggable
 
 @BackInTimeCompilerInternalApi
-internal fun <T : Any> captureThenReturnValue(
+internal fun <T : Any?> captureThenReturnValue(
     instance: BackInTimeDebuggable,
     ownerClassFqName: String,
     methodInvocationId: String,