The Complete Guide for Developers (ES2015 to Recent Versions)

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JavaScript has changed more in the last decade than in the twenty years before.

Modules, classes with private fields, promises and async/await, destructuring, iterators, optional chaining, Object.groupBy, iterator helpers — the language you write today is not the JavaScript of var and callbacks. Yet many developers learned it in pieces, a framework here and a tutorial there, and the gaps show up as confusing bugs: a surprising this, a swallowed promise rejection, a float that doesn't add up, or a frozen page.

This book gives you the complete, modern picture — how the language really works and how to use it well in the browser and on Node.js.

• 514 pages · 28 chapters + 4 appendices
• Every major feature from ES2015 to ES2025, with the edition that introduced it
• Types, coercion, scope, closures, and errors explained from first principles
• Objects, arrays, strings, regular expressions, numbers, dates, Intl, and collections
• Prototypes, this, classes with private members, iterators, generators, Proxy, and ES modules
• The event loop, promises, async/await, AbortController, fetch, and streams
• DOM, Web APIs, service workers, web components, Node.js, tooling, and testing
• Performance, security, modern idioms, and a complete end-to-end case study
• Proposals such as Temporal and decorators clearly labeled — no hype, no invented benchmarks

Table Of Contents

Part I — JavaScript Foundations

• Ch 1 · JavaScript Today: The Language, Its Runtimes, and ECMAScript Editions
• Ch 2 · Values, Types, and Operators
• Ch 3 · Variables and Scope: let, const, Hoisting, and the Temporal Dead Zone
• Ch 4 · Control Flow, Errors, and Debugging
• Ch 5 · Functions in Depth: Arrow Functions, Parameters, and Closures

Part II — Working with Data

• Ch 6 · Objects: Literals, Destructuring, Spread, and Optional Chaining
• Ch 7 · Arrays: Iteration Methods, Immutable Updates, and Grouping
• Ch 8 · Strings, Template Literals, Regular Expressions, and Unicode
• Ch 9 · Numbers, BigInt, Math, Dates, and Internationalization with Intl
• Ch 10 · Collections: Map, Set, WeakMap, WeakRef, and Structured Cloning

Part III — Objects, Classes, and Modules

• Ch 11 · Prototypes and this: How JavaScript Objects Really Work
• Ch 12 · Classes: Fields, Private Members, Static Blocks, and Inheritance
• Ch 13 · Iterators, Generators, and Iterator Helpers
• Ch 14 · Symbols, Proxy, Reflect, and Metaprogramming
• Ch 15 · ES Modules: import, export, Dynamic Import, and Top-Level Await

Part IV — Asynchronous JavaScript

• Ch 16 · The Event Loop: Call Stack, Tasks, and Microtasks
• Ch 17 · Promises in Depth: Chaining, Combinators, and Promise.withResolvers
• Ch 18 · async and await: Error Handling, Parallelism, and Async Iteration
• Ch 19 · Timers, Cancellation with AbortController, and Concurrency Patterns
• Ch 20 · Fetch and Streams: Working with Network Data

Part V — JavaScript in the Browser and on the Server

• Ch 21 · The DOM and Events in Modern Browsers
• Ch 22 · Web Platform APIs: Storage, Workers, Observers, and Web Components
• Ch 23 · Node.js Essentials: Modules, File System, Streams, and the Built-in Test Runner
• Ch 24 · Tooling: npm, Bundlers, Linters, Formatters, and Type Checking with JSDoc
• Ch 25 · Testing JavaScript: Unit, Integration, and Browser Tests

Part VI — Professional JavaScript

• Ch 26 · Performance, Memory, and Security
• Ch 27 · Modern Patterns and Idioms: Functional Techniques, Immutability, and Clean Code
• Ch 28 · Case Study: Building Ridgeline from Browser to Node.js

Appendices

• App A · Modern JavaScript Cheat Sheet
• App B · ES2015–ES2025 Feature Reference
• App C · Production Checklist
• App D · Glossary

WHO IT IS FOR
Developers coming from other languages, front-end developers who want to master the language beneath their frameworks, Node.js and full-stack developers, and experienced JavaScript developers catching up on everything since ES2015.

FORMAT
PDF (A4), 514 pages, English, clickable table of contents and PDF bookmarks. 1st Edition, 2026. Published by thenexbooks.

This book is independent and is not affiliated with or endorsed by Ecma International, TC39, Oracle, or the OpenJS Foundation.

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