# AWS AppSync resolver mapping template reference (VTL)
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**Note**  
We now primarily support the APPSYNC\_JS runtime and its documentation. Please consider using the APPSYNC\_JS runtime and its guides [here](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-reference-js-version.html).

The following sections will describe how utility operations can be used in mapping templates:
+  [ Resolver mapping template overview ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-mapping-template-reference-overview.html) - Learn more about how resolvers work in AWS AppSync.
+  [ Resolver mapping template programming guide ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-mapping-template-reference-programming-guide.html) - Learn more about basic VTL data structures and logic handling.
+  [ Resolver mapping template context reference ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-context-reference.html) - Learn more about the context map and how it's used in resolvers.
+  [ Resolver mapping template utility reference ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-util-reference.html) - Learn more about using utilities to simplify code.
+  [ Resolver mapping template reference for DynamoDB ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-mapping-template-reference-dynamodb.html) - Learn more about how resolvers interact with DynamoDB.
+  [ Resolver mapping template reference for RDS ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-mapping-template-reference-rds.html) - Learn more about resolver structure and interactions with RDS.
+  [ Resolver mapping template reference for OpenSearch ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-mapping-template-reference-elasticsearch.html) - Learn more about resolver request and response structure and interactions with OpenSearch Service.
+  [ Resolver mapping template reference for Lambda ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-mapping-template-reference-lambda.html) - Learn more about resolver request and response structure and interactions with Lambda.
+  [ Resolver mapping template reference for EventBridge ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-mapping-template-reference-eventbridge.html) - Learn more about resolver request and response structure and interactions with EventBridge.
+  [ Resolver mapping template reference for None data source ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-mapping-template-reference-none.html) - Learn more about resolver request and response structure and interactions with NONE data sources.
+  [ Resolver mapping template reference for HTTP ](https://docs.aws.amazon.com/appsync/latest/devguide/resolver-mapping-template-reference-http.html) - Learn more about resolver request and response structure and interactions with HTTP endpoints.