Exploring AWS Lambda Web Functions for building web applications

This article explores AWS Lambda Web Functions, a new Lambda function type that runs standard Node.js HTTP servers with automatic scaling and global routing capabilities.

• Deploy Node.js web servers with a single command to get public HTTPS endpoints with no adapter layer
• Web Functions handle multiple concurrent requests per environment, unlike Event Functions which serve one request at a time
• Active-CPU billing charges only for CPU time consumed, not wall-clock time spent waiting on I/O operations
• Supports multi-Region deployment with automatic latency-based routing through Route 53
• Includes authentication options: ApplicationManaged for public endpoints or IamAuth for service-to-service APIs
• Compatible with Node.js frameworks like Express, Fastify, and Hono without requiring adapters
• Provides concurrency controls via maxConcurrencyPerEnvironment, maxEnvironments, and rateLimit settings

Lambda Web Functions simplify serverless web application deployment by eliminating adapter layers and infrastructure management while providing built-in global scaling and routing.