An experimental programming language

Dovetail

A language for business logic.

Dovetail has records, enums, newtypes, typed errors, and structured concurrency. Programs compile to WebAssembly.

The compiler and libraries are in early development.

A small example

Quantity.dove

newtype Quantity private = Int32

module Quantity =
    public function make(value: Int32)
        : Result<Quantity, String> =
        if value > 0 then
            Ok(Quantity(value))
        else
            Error("Must be positive")

Here, construction is private. The make function checks the value and returns a typed result.

Try it

curl -fsSL https://dovetaillang.org/install.sh | sh

For macOS and Linux. See the getting started guide for Windows and PATH setup.

Documentation

All chapters

Getting started: Installation, editor setup, and a first program.
The language: Syntax, types, functions, and error handling.
Domain modeling: Value objects, entities, and application boundaries.
Async and resources: Running work and managing its lifetime.

For coding assistants, the same book is available as Markdown.