# 82007: Unsupported Runtime

Log Type: APPLICATION

Log Level: ERROR

## Description

The runtime used in the Serverless Build request is not supported on the platform. A runtime defines the environment your Functions will be executed in (e.g. which Node.js version to use for your Functions).

### Possible causes

* A Serverless Build request was made without providing the runtime and the runtime used for the last successful build in the service (e.g. a Node.js version that is no longer supported on the platform).
* A Serverless Build request was made with a specified runtime (e.g. node10) that is currently not supported on the platform.

### Possible solutions

* Determine what [runtime versions are currently available](/docs/serverless/functions-assets/faq#which-runtimes-are-available-for-twilio-functions).
* Migrate to a new valid Node.js version by following our migration guide: [https://www.twilio.com/docs/serverless/functions-assets/node-upgrade](/docs/serverless/functions-assets/node-upgrade)
* When using the Serverless API pass a dedicated valid runtime version when creating a new Build: [https://www.twilio.com/docs/serverless/api/resource/build](/docs/serverless/api/resource/build)