# AWS Lambda Execution Role [TOC] --- ## The built-in AWSLambdaBasicExecutionRole > …you can use the built-in `AWSLambdaBasicExecutionRole`, as these functions **don't call other AWS services**. ## Defining Lambda function permissions with an execution role > If your Lambda function **calls other AWS services**, you'll need to assign an IAM execution role to the Lambda function. ## References - [Use API Gateway Lambda authorizers » Additional examples of Lambda authorizer functions](https://docs.aws.amazon.com/apigateway/latest/developerguide/apigateway-use-lambda-authorizer.html#api-gateway-lambda-authorizer-lambda-function-create) - [Defining Lambda function permissions with an execution role](https://docs.aws.amazon.com/lambda/latest/dg/lambda-intro-execution-role.html)