Windows

Note: Linux is the reference platform. Windows is supported via bundled JRE and the varyup toolchain manager.

Quick install

One command installs varyup (the toolchain manager) and the latest Vary toolchain.

Open PowerShell and run:

irm https://github.com/ccollicutt/vary/releases/latest/download/install.ps1 | iex

This will download varyup.exe to %LOCALAPPDATA%\vary\bin\, install the latest Vary toolchain, and install the vary.exe compiler shim.

Then add %LOCALAPPDATA%\vary\bin to your user PATH:

$path = [Environment]::GetEnvironmentVariable("Path", "User")
[Environment]::SetEnvironmentVariable("Path", "$env:LOCALAPPDATA\vary\bin;$path", "User")

Note: The installer does not modify your PATH automatically. Adding the PATH entry is a manual step by design, so nothing is changed in your environment without your knowledge.

Open a new terminal, then verify:

vary --version

You should see:

Vary vX-alpha.Y

Options

Parameter	Effect
-SkipToolchain	Skip automatic toolchain install

Environment variables VARY_HOME (default: %LOCALAPPDATA%\vary) and VARY_RELEASE_URL can override defaults.

Manual install

If you prefer not to pipe to iex, you can install manually:

1. Download varyup

$varyBin = "$env:LOCALAPPDATA\vary\bin"
mkdir $varyBin -ErrorAction SilentlyContinue
Invoke-WebRequest "https://github.com/ccollicutt/vary/releases/latest/download/varyup-windows-x64.exe" -OutFile "$varyBin\varyup.exe"

2. Verify checksum

$sums = (Invoke-WebRequest "https://github.com/ccollicutt/vary/releases/latest/download/SHA256SUMS" -UseBasicParsing).Content
$expected = (($sums -split "`n") | Where-Object { $_ -match "varyup-windows-x64.exe$" }) -split "\s+" | Select-Object -First 1
$actual = (Get-FileHash "$varyBin\varyup.exe" -Algorithm SHA256).Hash.ToLower()
if ($actual -ne $expected) { Write-Error "Checksum mismatch! Expected $expected, got $actual" }
else { Write-Host "Checksum verified" }

If the check fails, delete the binary and retry the download.

3. Add to PATH

$varyBin = "$env:LOCALAPPDATA\vary\bin"
$path = [Environment]::GetEnvironmentVariable("Path", "User")
if ($path -notlike "*$varyBin*") {
    [Environment]::SetEnvironmentVariable("Path", "$path;$varyBin", "User")
    $env:Path += ";$varyBin"
}

Or add %LOCALAPPDATA%\vary\bin through Settings > System > About > Advanced system settings > Environment Variables > User Path.

Open a new terminal and install a toolchain:

varyup toolchain install latest

Managing toolchains

List available versions:

varyup toolchain list-available

Install a specific version:

varyup toolchain install <version>

Short aliases are available:

varyup tc la   # list-available
varyup tc i    # install

Run varyup with no arguments to see all commands and aliases.

Install VS Code extension

Each toolchain bundles the Vary VS Code extension. Install it with:

varyup vscode install

See VS Code for full extension documentation.

Next steps

Action	Link
Manage versions, update, pin per-project	varyup
Write your first program	Getting Started
Run vary test on examples	Testing
Run vary mutate on examples	Mutation testing