Books
Web Performance
Book Of Speed

This book gives you practical industry examples and studies which expose the effects of performance on the bottom line
Author : Stoyan Stefanov - Github
High Performance Browser Networking

This book provides a hands-on overview of what every web developer needs to know about the various types of networks (WiFi, 3G/4G), transport protocols (UDP, TCP, and TLS), application protocols (HTTP/1.1, HTTP/2), and APIs available in the browser (XHR, WebSocket, WebRTC, and more) to deliver the best—fast, reliable, and resilient—user experience.
Mature Optimization

The trickiest part of speeding up a program is not doing it, but deciding whether it’s worth doing at all. There are few clear principles, only rules of thumb
Web Services
RESTful Web Services

This book puts the "Web" back into web services. It shows how you can connect to the programmable web with the technologies you already use every day. The key is REST, the architectural style that drives the Web.
Authors : Leonard Richardson and Sam Ruby
Search Engines
Search Engines: Information Retrieval In Practice

This book is ideal for introductory information retrieval courses at the undergraduate and graduate level in computer science, information science and computer engineering departments. It is also a valuable tool for search engine and information retrieval professionals.
Authors : W. Bruce Croft, Donald Metzler, Trevor Strohman