minify-js

Extremely fast JavaScript minifier, written in Rust.

Goals

• Fully written in Rust for maximum compatibility with Rust programs and derivatives (FFI, WASM, embedded, etc.).
• Maximises performance on a single CPU core for simple efficient scaling and easy compatible integration.
• Minification of individual inputs/files only; no bundling or transforming.
• Prefer minimal complexity and faster performance over maximum configurability and minimal extra compression.

Features

• Fast parsing powered by SIMD instructions and lookup tables.
• Minification of identifiers.

Usage

CLI

Precompiled binaries are available for Linux, macOS, and Windows.

Linux x64 | macOS x64 | Windows x64

Use the --help argument for more details.

bash minify-js --output /path/to/output.min.js /path/to/src.js

Rust

Add the dependency:

toml [dependencies] minify-js = "0.1.1"

Call the method:

```rust use minify_js::minify;

let mut code: &[u8] = b"let x = 1;"; let mut out = Vec::new(); minify(code.tovec(), &mut out).unwrap(); asserteq!(out.as_slice(), b"let x=1"); ```

In progress

• Combine and reorder declarations.
• Omit more semicolons, spaces, parentheses, and braces.
• Minify import and export syntax.
• More extensive testing, especially over rare syntax.
• Evaluation and folding of constant expressions.
• Parse and erase TypeScript syntax.
• FFI libraries for other languages.
• Aliasing of reused well-knowns.
• Removal of unreachable and redundant code.
• Aliasing frequently accessed properties and called methods.
• Better support for non-ASCII identifiers.
• Replacing if statements with conditional and logical expressions.
• Aliasing repeated identical literal values.
• Micro-optimisations:
  • Unwrap string literal computed members, then identifier or number string members.
  • Replace x === null || x === undefined with x == null, where x is side-effect free.
  • Using shorthand properties and Object.assign.
  • (Dangerous) Replace functions without use of this with arrow functions.
  • Replace void x with undefined, where x is side-effect free.
  • Replace return undefined with return.
  • Replace const with let.
  • Hoist let and const.
  • Unwrapping blocks.
  • Unwrapping paretheses, altering expressions as necessary.