Feature Flags

zesven uses Cargo features to enable optional functionality.

Default Features

These features are enabled by default:

[dependencies]
zesven = "3.2"  # Includes default features

Feature	Description
lzma	LZMA compression
lzma2	LZMA2 compression (includes lzma)
deflate	Deflate/zlib compression
bzip2	BZip2 compression
ppmd	PPMd compression
aes	AES-256 encryption
parallel	Multi-threaded compression
sysinfo	Sizing the memory budget from the machine

Minimal Build

Disable defaults for a smaller binary:

[dependencies]
zesven = { version = "3.2", default-features = false, features = ["lzma2"] }

All Features

Compression

Feature	Default	Description
lzma	Yes	LZMA compression via lzma-rust2
lzma2	Yes	LZMA2 compression (includes lzma)
deflate	Yes	Deflate via zlib-rs
bzip2	Yes	BZip2 compression
ppmd	Yes	PPMd compression
lz4	No	LZ4 fast compression
zstd	No	Zstandard compression
brotli	No	Brotli compression

Built-in codecs (always available, no feature flag required):

• LZ5 - Pure Rust implementation
• Lizard - Pure Rust implementation

Security

Feature	Default	Description
aes	Yes	AES-256 encryption

Performance

Feature	Default	Description
parallel	Yes	Multi-threaded with Rayon
sysinfo	Yes	Lets MemoryLimit::Auto ask the machine how much memory it has. Without it, Auto falls back to a fixed 512 MiB on an uncapped machine, which bounds a large one to a handful of encoders; a cgroup cap is honoured either way.

APIs

Feature	Default	Description
async	No	Tokio-based async API
regex	No	Regex-based filtering
cli	No	Command-line interface

Platform

Feature	Default	Description
wasm	No	WebAssembly support
wasm-default	No	WASM with default codecs

Feature Dependencies

Some features depend on others:

lzma2 → lzma
aes → lzma2          (encrypted headers are stored compressed)
cli → aes            (the tool prompts for passwords and opens encrypted archives)
async → tokio, tokio-util
wasm → wasm-bindgen, wasm-bindgen-futures, js-sys, web-sys, getrandom/js
wasm-default → wasm, lzma, lzma2, deflate, bzip2, ppmd, aes

Example Configurations

Web Server

[dependencies]
zesven = { version = "3.2", features = ["async"] }

CLI Tool

[dependencies]
zesven = { version = "3.2", features = ["cli", "zstd", "lz4"] }

Embedded System

[dependencies]
zesven = { version = "3.2", default-features = false, features = ["lzma2"] }

Browser (WASM)

[dependencies]
zesven = { version = "3.2", default-features = false, features = ["wasm-default"] }

Maximum Compatibility

[dependencies]
zesven = { version = "3.2", features = ["lz4", "zstd", "brotli"] }

Binary Size Impact

Approximate binary size impact (release build):

Configuration	Size
Minimal (lzma2 only)	~500 KB
Default features	~1.5 MB
All features	~3 MB

See Also

• Compression Options - Using compression methods
• Async API - Async feature usage
• WASM - WebAssembly usage