ZZ

Fast systems language: native AOT, green threads, zero GC pauses.

Website | Getting started | Learn | Documentation | Contributing

Why ZZ?

• Native binaries via zz build, fast iteration via zz run.
• Green threads and channels for concurrent pipelines.
• Inferred types, pipelines (|>), pattern matching.
• Diagnostics that suggest fixes, plus zz fix and zz fmt.
• Batteries included: HTTP, JSON, fs, math, SQL.

How is ZZ different from Rust?

ZZ is not syntactic sugar on top of Rust. It is an independent language with its own frontend, type checker, tree-walk VM, and AOT backend (ZZ → C → native binary), plus its own standard library.

• Memory without a borrow checker. ZZ has value semantics: functions receive copies from the programmer's perspective, there are no references, no lifetimes, no &/&mut. The compiler/runtime may elide copies internally (copy-on-write, in-place slots), but aliasing is never observable. Rust gives you control via ownership/borrows; ZZ trades that control for simpler reasoning.
• Concurrency model. ZZ ships green threads and channels as the default pipeline primitive. No async/executors to wire up for the common case.
• Scope. ZZ targets services, CLIs, and data pipelines with batteries included (HTTP, JSON, fs, SQL). It cannot do everything Rust can: no unsafe, no zero-cost abstractions, no no_std/embedded, no manual layout control. For those, use Rust (including as a ZZ native plugin).
• Interop. ZZ plugins speak C ABI (plugin.zzi); Rust crates can back plugins, but the ZZ side never exposes Rust semantics.

Quick start

Install (main way, latest GitHub release). Re-run to update:

curl -fsSL https://zz-lang.pages.dev/install.sh | sh

Windows:

irm https://zz-lang.pages.dev/install.ps1 | iex

Verify:

zz --version
zz setup    # PATH + shell completions for bash/zsh/fish (run once)

Hello world (hello.zz):

name := input("What is your name? ")
println("Hello, {name}!")

zz run hello.zz

REPL, check, format:

zz            # REPL (:help, :quit)
zz check src/
zz fmt src/

Install a project as a tool (~/.zz/bin):

zz install --path .

Keep the toolchain healthy:

zz upgrade   # self-update to the latest release
zz doctor    # audit binary, clang, shell, git, registry (add --fix)

Documentation

• Getting started
• Syntax
• Language reference
• Standard library
• Playground

Contributing

See CONTRIBUTING.md for setup, tests, and PRs.

License

Apache-2.0 — see LICENSE.