---
url: >-
  https://adk.nht.io/api/@nhtio/adk/batteries/variables/E_ISOLATE_FUNCTION_UNSERIALIZABLE.md
description: >-
  Thrown when the function passed to [`isolateFunction`](https://adk.nht.io/api/@nhtio/adk/batteries/functions/isolateFunction) cannot be
  serialized — `@nhtio/encoder/function_serializer`'s
  `FunctionSerializer.canSerialize` rejects native functions (`fn.toString()`
  containing `[native code]`) and bound functions (which stringify the same
  way). Fatal: detected before any Worker is spawned; there is no fallback
  representation to fall back to.
---

# Variable: E\_ISOLATE\_FUNCTION\_UNSERIALIZABLE

```ts
const E_ISOLATE_FUNCTION_UNSERIALIZABLE: CreatedException<[string]>;
```

Defined in: [src/batteries/isolation/isolate\_function.ts:87](https://github.com/NHTIO/ADK/blob/v1.20260713.1/src/src/batteries/isolation/isolate_function.ts#L87)

Thrown when the function passed to [isolateFunction](../functions/isolateFunction.md) cannot be serialized —
`@nhtio/encoder/function_serializer`'s `FunctionSerializer.canSerialize` rejects native functions
(`fn.toString()` containing `[native code]`) and bound functions (which stringify the same way).
Fatal: detected before any Worker is spawned; there is no fallback representation to fall back to.