Reussir Language Reference

Installation

Installation

The prebuilt release is the shortest route to a working Reussir toolchain. It contains rrcrrc, the ahead-of-time compiler; renerene, the package and build manager; and rreplrrepl, the interactive REPL. LLVM, MLIR, and the Reussir backend are already linked into the tools, so they do not need to be installed separately. Rust does need to be available on the host because renerene compiles the bundled Reussir runtime source for a program when it is first needed.

1. Install Rust nightly

Install rustuprustup by following the official Rust installer, then open a new terminal. Reussir currently pins nightly-2026-02-15nightly-2026-02-15; the host must provide that nightly or a later one. The exact pinned version is the most reproducible choice:

rustup toolchain install nightly-2026-02-15 --component rust-src
rustup default nightly-2026-02-15
rustc --version
cargo --version
rustup toolchain install nightly-2026-02-15 --component rust-src
rustup default nightly-2026-02-15
rustc --version
cargo --version

Changing the default affects every Rust project. To keep another global default, set a directory-specific override inside the directory that will hold your Reussir project instead:

mkdir my-reussir-project
cd my-reussir-project
rustup override set nightly-2026-02-15
mkdir my-reussir-project
cd my-reussir-project
rustup override set nightly-2026-02-15

If rustcrustc already reports a nightly dated 2026-02-15 or later and cargocargo is on PATHPATH, no additional Rust installation is required.

2. Choose a release channel

Reussir publishes two release tags:

  • Stable v0.1.0 is a fixed, versioned release. Start here when following the documentation or when a reproducible compiler version matters.
  • Nightly tracks the latest successful build from mainmain. The nightlynightly tag and its release are replaced after new changes land, and archive names contain the build date.

Both channels are produced by the same build-and-test matrix. Pick the stable release unless you need a feature or fix that has not reached a versioned release.

3. Download the archive for the host

Open the chosen release page and download the matching asset:

  • Linux x86_64: reussir-v0.1.0-linux-x86_64.tar.xzreussir-v0.1.0-linux-x86_64.tar.xz
  • Linux AArch64: reussir-v0.1.0-linux-aarch64.tar.xzreussir-v0.1.0-linux-aarch64.tar.xz
  • macOS Apple silicon: reussir-v0.1.0-macos-arm64.tar.xzreussir-v0.1.0-macos-arm64.tar.xz
  • Windows x64: reussir-v0.1.0-windows-x64-msvc.zipreussir-v0.1.0-windows-x64-msvc.zip

Nightly uses the same platform suffixes, with a dated prefix such as reussir-nightly-YYYY-MM-DD-linux-x86_64.tar.xzreussir-nightly-YYYY-MM-DD-linux-x86_64.tar.xz. There is currently no prebuilt archive for Intel macOS, Windows on Arm, or other platforms; use the source-build guide on those hosts.

4. Extract the toolchain

On Linux or macOS, create an installation directory and unpack the tar.xztar.xz archive into it. This example uses the stable Linux x86_64 archive:

mkdir -p "$HOME/.local/opt"
tar -xJf reussir-v0.1.0-linux-x86_64.tar.xz -C "$HOME/.local/opt"
mkdir -p "$HOME/.local/opt"
tar -xJf reussir-v0.1.0-linux-x86_64.tar.xz -C "$HOME/.local/opt"

The macOS and AArch64 archives use the same command with their respective file names.

On Windows, extract the ZIP archive with File Explorer or PowerShell:

Expand-Archive .\reussir-v0.1.0-windows-x64-msvc.zip `
  -DestinationPath "$env:LOCALAPPDATA\Programs"
Expand-Archive .\reussir-v0.1.0-windows-x64-msvc.zip `
  -DestinationPath "$env:LOCALAPPDATA\Programs"

Each archive contains a single top-level directory with a binbin subdirectory.

5. Put binbin on PATHPATH

On Linux or macOS, add the extracted binbin directory to the appropriate shell startup file, such as ~/.profile~/.profile, ~/.bashrc~/.bashrc, or ~/.zshrc~/.zshrc:

export PATH="$HOME/.local/opt/reussir-v0.1.0-linux-x86_64/bin:$PATH"
export PATH="$HOME/.local/opt/reussir-v0.1.0-linux-x86_64/bin:$PATH"

Adjust the directory name for macOS, AArch64, or a dated nightly build, then open a new terminal or source the edited startup file.

On Windows, add the following directory to the user PathPath in Settings → System → About → Advanced system settings → Environment Variables:

%LOCALAPPDATA%\Programs\reussir-v0.1.0-windows-x64-msvc\bin
%LOCALAPPDATA%\Programs\reussir-v0.1.0-windows-x64-msvc\bin

For only the current PowerShell session, the equivalent is:

$env:Path = "$env:LOCALAPPDATA\Programs\reussir-v0.1.0-windows-x64-msvc\bin;$env:Path"
$env:Path = "$env:LOCALAPPDATA\Programs\reussir-v0.1.0-windows-x64-msvc\bin;$env:Path"

6. Verify the installation

The release workflow checks that every packaged command can start in a clean environment. Run the same smoke test after installation:

rrc --help
rene --help
rrepl --help
rrc --help
rene --help
rrepl --help

All three commands should print help without an LLVM or MLIR shared-library error. Keep rustcrustc and cargocargo on PATHPATH: the first renerene package build may take longer while it compiles the embedded reussir-rtreussir-rt runtime for the host.

To work on the compiler itself, continue with Building Reussir.