AWS re:Invent 2025 - Accelerate building Serverless apps with Amazon Q and MCP servers (CNS373)

Accelerating Serverless App Development with Amazon Kiro and MCP Servers

Overview

• This session focused on how to leverage Amazon Kiro (formerly Amazon Q) and MCP (Model Context Protocol) servers to rapidly build and deploy serverless applications.
• The presenters, Sean Kendall and Brian Zambrano, are AWS experts in serverless and generative AI technologies.
• The session covered a live coding demo to build a serverless backend for a tic-tac-toe game using Kiro and various MCP servers.

Amazon Kiro

• Kiro is an AI-powered developer tool that enables faster application development through intelligent code generation and automation.
• The session covered two ways to use Kiro:
  1. Kiro CLI: A command-line interface that allows developers to provide prompts and let Kiro handle the code generation.
  2. Kiro IDE: An integrated development environment (IDE) based on VS Code that provides a graphical interface for interacting with Kiro.

MCP Servers

• MCP (Model Context Protocol) servers are a way to provide Kiro with access to external data and services to enhance its capabilities.
• MCP servers act as a standardized interface to backend systems, allowing Kiro to integrate with APIs, databases, and other resources.
• The session highlighted several MCP servers available, including:
  • AWS Serverless MCP Server: Provides integration with AWS Serverless Application Model (SAM) for building and deploying serverless applications.
  • AWS CDK MCP Server: Enables Kiro to generate AWS CDK (Cloud Development Kit) code for infrastructure as code.
  • AWS Core MCP Server: Offers prompt understanding and routing to other MCP servers.
  • AWS Documentation MCP Server: Provides Kiro with access to the latest AWS documentation, ensuring generated code uses up-to-date information.
  • Fetch MCP Server: Allows Kiro to fetch data from the internet, such as API specifications.

Prompt Engineering

• The presenters demonstrated the importance of prompt engineering, showing how they crafted a detailed prompt to guide Kiro in building the tic-tac-toe backend.
• The prompt included instructions to:
  • Build and deploy the backend
  • Use the Fetch MCP server to retrieve the API specification
  • Deploy to the presenter's default AWS account
  • Perform testing to ensure the API is working as expected
  • Handle CORS headers and tagging

Live Coding Demo

• The presenters showed the Kiro CLI and IDE in action, demonstrating how they used Kiro to rapidly build and deploy the serverless tic-tac-toe backend.
• The Kiro CLI version allowed the presenter to provide the prompt and let Kiro handle the entire development process, including deployment and testing.
• The Kiro IDE version showcased the ability to configure MCP servers, create agent steering documents to guide Kiro, and monitor the code generation process.
• The demo highlighted Kiro's ability to handle errors and iteratively improve the generated code based on feedback.

Key Takeaways

• Kiro and MCP servers enable significantly faster development of serverless applications by automating code generation and infrastructure provisioning.
• Prompt engineering is crucial for guiding Kiro to generate the desired code and infrastructure, with the presenters providing a detailed example.
• MCP servers provide a standardized way for Kiro to access external data and services, enhancing its capabilities and allowing it to build more robust applications.
• The presenters demonstrated the ability to build a working serverless backend in a matter of minutes, highlighting the potential time and cost savings of using Kiro and MCP servers.

Business Impact

• The use of Kiro and MCP servers can dramatically accelerate the development of serverless applications, allowing businesses to bring new products and features to market more quickly.
• By automating repetitive tasks and infrastructure provisioning, developers can focus on higher-value work, improving overall productivity and efficiency.
• The integration with external data and services through MCP servers enables the creation of more sophisticated and feature-rich applications, providing a competitive advantage.
• The ability to rapidly iterate and improve generated code based on feedback can lead to higher-quality, more reliable applications.

Examples

• The presenters built a serverless tic-tac-toe backend using Kiro and various MCP servers, including the AWS Serverless, AWS CDK, and Fetch MCP servers.
• The generated code included Lambda functions, API Gateway integration, and DynamoDB table provisioning, all deployed using AWS SAM.
• Kiro was able to handle errors and iteratively improve the generated code, demonstrating its ability to learn and refine the application over time.