The Spring Pocket Guide is a fast-paced, practical tour of modern Spring development, from your first project to production-ready, AI-integrated systems. Starting with Spring Boot and Java 24+, you’ll build a complete microservice-style architecture around a fictional project. Along the way, you’ll explore HTTP endpoints, REST with HATEOAS, GraphQL schemas and resolvers, and high-performance gRPC services. You’ll integrate PostgreSQL (including vector support), consume external APIs with RestClient and declarative interface clients, and secure everything using Spring Security and OAuth 2. But this isn’t just about traditional web services. You’ll go further, building an AI-powered assistant with Spring AI, implementing retrieval-augmented generation (RAG), enabling tool calling, and exposing services through the emerging Model Context Protocol (MCP). The result is a modern, AI-ready Spring architecture built entirely on the “real web”, HTTP. By the end of this guide, you’ll understand how to build secure, scalable, cloud-native, and AI-integrated systems using Spring’s latest capabilities.