Install

Core 0.3.0 (7 October 2026) ships prebuilt binaries for Linux x86-64, macOS Intel and macOS Apple Silicon. You do not need OCaml, opam or Dune.

curl -fsSL https://raw.githubusercontent.com/jbwinters/jacquard-lang/jacquard-core-0.3.0/scripts/install.sh | sh
export PATH="$HOME/.local/bin:$PATH"
jac --version

The installer downloads the release archive for your platform, checks it against the published SHA-256 file, and installs the jacquard command (with its short alias jac), the standard prelude, the demos and the C runtime used by native builds.

JACQUARD_INSTALL_PREFIX chooses a different prefix (the default is ~/.local).
JACQUARD_INSTALL_VERSION chooses another release tag.
To read the script first, open scripts/install.sh at the release tag. Archives and checksums are on the release page.

Check that it works

jac run ~/.local/share/jacquard/demos/basics/m1-fact.jac

This prints 120. Then run the case study from the tour:

sh ~/.local/share/jacquard/demos/case-studies/release-risk/run.sh

Your first program

Save this as greet.jac:

greet(name) = {
  println(text.concat("hello ", name))
  text.length(name)
}

greet("reviewer")

jac check greet.jac --print-sigs shows its inferred effects, jac run greet.jac --allow console runs it, and jac build compiles it to a standalone native binary through generated C (a C compiler must be installed):

$ jac build greet.jac -o greet && ./greet --allow console
hello reviewer
8

The native backend covers a documented subset of the language; see the native compilation notes.

From source

Building the implementation needs OCaml 5 through opam. The README and SKILL.md describe the repository-local switch and the development gate.