UglifyJS

UglifyJS is one of the best tools to improve the performance of your JavaScript code and preparing it for production environments.

Initially developed for Node.js, UglifyJS now works on any JavaScript platform, also supporting the CommonJS module system.

The UglifyJS toolkit was mainly created for source code minification, achieving this with great results while also leaving the semantics of the code intact in most cases.

Along the way, the project has added lots of new features, amongst them the ability to parse, analyze, and transform the AST of a block of JS code.

This gives the developers lots of tweakable options in the UglifyJS engine, allowing him a fine tune control over how the source code is compressed or how compressed source is beatified at later points.

Since its launch, the project has gained a big following in the JavaScript community and has been used in many other JS (Node.js especially) projects.

Features:

• Remove comments
• Optionally leave some comments in the code
• Leave copyright notices intact
• Shorten variable names
• Regenerate code from an AST
• Remove block brackets
• Join consecutive var declarations
• Resolve simple constant expressions
• Optimizations for IF statements
• Consecutive statements in blocks are merged into one sequence
• Remove some unreachable code and warn about it
• Source maps support
• Included scope analyzer
• Works with client-side (browsers) and server-side (Node.js) environments
• Usable from the Node.js CLI
• Well-documented

Requirements:

• JavaScript enabled on client side