Zolo language v0.1.8-alpha MIT

From many ideas, a language of its own.

Static types, fluent composition, and integrated tooling. The same .zolo file runs across the Lua ecosystem, as a native binary, or in WebAssembly.

Try in Playground View Docs

.zolo effects.zolo

source / output

effect Clock { fn now() -> str }

fn announce(message: str) with Clock -> str {
    let time = perform Clock::now()
    "{time} · {message}"
}

let line = handle announce("build ready") with {
    Clock::now() => "09:42",
}
print(line)

stdout 09:42 · build ready

01 / language

The language in three ideas

Composition reads top to bottom. Safety stays explicit. The toolchain ships together.

01 composition

Pipe Operator |>

Chain transformations like a functional pipeline. No nested callbacks, no temp variables.

"hello"
    |> String.upper()
    |> String.trim()
    |> print()

02 safety

Pattern Matching

Optional types T?, optional chaining ?. and null coalesce ?? eliminate NPEs by design.

let city = user?.address?.city ?? "Unknown"

match result {
    .Ok(value) => value,
    .Err(error) => report(error),
}

03 toolchain

Tooling first

LSP with autocomplete and hover, DAP debugger, formatter, VS Code extension and REPL — all out-of-the-box with no configuration.

zolo run app.zolo
zolo check app.zolo
zolo test
zolo build --release

02 / examples

See it in action

Small, complete programs you can open, change, and run in the browser.

hello.zolo ▶ Playground

let name = "Zolo"
print("Hello, {name}!")
print("Version: {1 + 1}.0")

stdout

Hello, Zolo!
Version: 2.0

03 / architecture

Source .zolo

UTF-8 text · the program you wrote

Architecture

01 source .zolo

02 front-end parse + typeck

03 middle-end ZoloIR

04 backends

VMnativeLLVMwasm-aot

04 / toolchain

One toolchain

Compiler, editor intelligence, formatter, and debugger follow the same language model.

01 CLI

run, build, check, test, fmt, repl

zolo run hello.zolo 02 LSP

Autocomplete, hover, go-to-definition, inlay hints

zolo-lsp 03 VS Code

Extension with syntax highlighting and LSP integration

ext install zolo 04 Formatter

Automatic AST-based formatting

zolo fmt file.zolo

05 / start

Write your first .zolo file.

Start in the browser, then take the same source to the CLI when you are ready.

Open Playground View Docs