Build a serverless app with Node.js and OpenWhisk

Serverless architecture allows developers to build and deploy applications without managing servers, offering advantages such as high scalability, quick deployment, and reduced costs. Apache OpenWhisk, a mature and feature-rich serverless framework developed by the Apache Software Foundation, supports multiple programming languages and provides an open-source alternative to mainstream platforms like AWS Lambda and Azure Functions, helping avoid vendor lock-in. The text outlines how to set up OpenWhisk locally using Docker and Kubernetes, develop a serverless Node.js app, and utilize the Serverless framework to deploy functions. It demonstrates creating web actions, triggers, rules, and sequences, with practical examples, such as sending Slack messages upon new user creation. By leveraging OpenWhisk's event-driven programming model, developers can build flexible and extensible applications that integrate with external APIs and perform multiple tasks sequentially.