Understand the important aspects of implementing a production-grade language server in support of language-smart tools such as code editors and other programming utilities. This book shows you how to create a single implementation of a language server that can be used by multiple tools, enabling you to do the job once in a way that can be shared and reused. This book covers the language server protocol used for communication between programming tools and your language server. The book also provides an in-depth understanding of the design, implementation, and user experience aspects which should be considered when implementing a language server. The book walks you through an example language server implementation to illustrate the basic concepts, then goes on to cover advanced aspects of language server use such as progress reporting, launchers, and extension points. User experience is an important aspect of language server implementation and different tooling vendors strive to provide their own unique user experiences. This book explains how the protocol features can be leveraged to address the unique developer experience provided by different tooling vendors. The book also shows how to enhance the smoothness of the editing experience by orchestrating multiple features together.