feat: support --prerelease in install scripts

README.md

@@ -42,6 +42,10 @@ curl -fsSL https://raw.githubusercontent.com/microsoft/modernize-cli/main/script
 
 The script automatically downloads the latest release, install the modernize bundle to `~/.local/share/modernize`, place the `modernize` command in `~/.local/bin`, and add the command directory to your PATH.
 
+> [!TIP]
+> To install the latest prerelease instead, append `--prerelease`:
+> `curl -fsSL https://raw.githubusercontent.com/microsoft/modernize-cli/main/scripts/install.sh | sh -s -- --prerelease`
+
 After installation, reload your shell profile to apply the PATH update:
 ```bash
 source ~/.bashrc   # or source ~/.zshrc for Zsh
@@ -67,6 +71,10 @@ winget install GitHub.Copilot.modernization.agent --silent
 iex (irm https://raw.githubusercontent.com/microsoft/modernize-cli/main/scripts/install.ps1)
 ```
 
+> [!TIP]
+> To install the latest prerelease instead, run with `-Prerelease`:
+> `& ([scriptblock]::Create((irm https://raw.githubusercontent.com/microsoft/modernize-cli/main/scripts/install.ps1))) -Prerelease`
+
 **Option 3 — MSI installer:**
 
 Download and run the latest MSI from the [Releases page](https://github.com/microsoft/modernize-cli/releases/latest).

scripts/install.ps1

@@ -7,10 +7,13 @@
     version, extracts the binary, and adds it to the current user PATH.
 .PARAMETER InstallDir
     Directory to install modernize into. Defaults to %LOCALAPPDATA%\Programs\modernize.
+.PARAMETER Prerelease
+    Install the latest prerelease instead of the latest stable release.
 #>
 [CmdletBinding()]
 param(
-    [string]$InstallDir = (Join-Path (Join-Path $env:LOCALAPPDATA 'Programs') 'modernize')
+    [string]$InstallDir = (Join-Path (Join-Path $env:LOCALAPPDATA 'Programs') 'modernize'),
+    [switch]$Prerelease
 )
 
 $ErrorActionPreference = 'Stop'
@@ -73,18 +76,27 @@ if (Get-Command gh -ErrorAction SilentlyContinue) {
 
 # --- Fetch latest release ---
 
-Write-Info 'Fetching latest release...'
-
 $apiHeaders = @{ Accept = 'application/vnd.github+json'; 'User-Agent' = 'modernize-installer' }
 
+if ($Prerelease) {
+    Write-Info 'Fetching latest prerelease...'
+    $releaseUri = "https://api.github.com/repos/$GitHubRepo/releases?per_page=1"
+} else {
+    Write-Info 'Fetching latest release...'
+    $releaseUri = "https://api.github.com/repos/$GitHubRepo/releases/latest"
+}
+
 try {
     $release = Invoke-RestMethod `
-        -Uri     "https://api.github.com/repos/$GitHubRepo/releases/latest" `
+        -Uri     $releaseUri `
         -Headers $apiHeaders
 } catch {
     Exit-Error "Failed to fetch release info from GitHub: $_"
 }
 
+# The list endpoint returns an array (newest first); select the first release.
+if ($release -is [System.Array]) { $release = $release[0] }
+
 $tag     = $release.tag_name
 $version = $tag -replace '^v', ''
 

scripts/install.sh

@@ -3,13 +3,35 @@ set -e
 
 GITHUB_REPO="microsoft/modernize-cli"
 MIN_GH_VERSION="2.45.0"
+PRERELEASE=0
 
 # --- Helpers ---
 
 info()    { printf '\033[0;32m[info]\033[0m  %s\n' "$*"; }
 warn()    { printf '\033[0;33m[warn]\033[0m  %s\n' "$*" >&2; }
 error()   { printf '\033[0;31m[error]\033[0m %s\n' "$*" >&2; exit 1; }
 
+usage() {
+    cat <<'EOF'
+Usage: install.sh [options]
+
+Options:
+  --prerelease   Install the latest prerelease instead of the latest stable release
+  -h, --help     Show this help message and exit
+EOF
+}
+
+# --- Parse arguments ---
+
+while [ $# -gt 0 ]; do
+    case "$1" in
+        --prerelease) PRERELEASE=1 ;;
+        -h|--help)    usage; exit 0 ;;
+        *)            usage >&2; error "Unknown option: $1" ;;
+    esac
+    shift
+done
+
 version_lt() {
     # Returns 0 (true) if $1 < $2
     awk -v v1="$1" -v v2="$2" 'BEGIN {
@@ -72,17 +94,23 @@ fi
 
 # --- Fetch latest release version ---
 
-info "Fetching latest release..."
+if [ "$PRERELEASE" -eq 1 ]; then
+    info "Fetching latest prerelease..."
+    RELEASE_API="https://api.github.com/repos/${GITHUB_REPO}/releases?per_page=1"
+else
+    info "Fetching latest release..."
+    RELEASE_API="https://api.github.com/repos/${GITHUB_REPO}/releases/latest"
+fi
 
 if command -v curl > /dev/null 2>&1; then
     RELEASE_JSON=$(curl -fsSL \
         -H "Accept: application/vnd.github+json" \
-        "https://api.github.com/repos/${GITHUB_REPO}/releases/latest") \
+        "$RELEASE_API") \
         || error "Failed to fetch release info from GitHub."
 elif command -v wget > /dev/null 2>&1; then
     RELEASE_JSON=$(wget -qO- \
         --header="Accept: application/vnd.github+json" \
-        "https://api.github.com/repos/${GITHUB_REPO}/releases/latest") \
+        "$RELEASE_API") \
         || error "Failed to fetch release info from GitHub."
 else
     error "Neither curl nor wget found. Please install one of them."

specs/install.md

@@ -8,7 +8,9 @@
 
 3) Obtain a GitHub token via `gh auth token` (if gh CLI is available and authenticated)
 
-4) Fetch the latest release metadata from the GitHub API (`api.github.com/repos/.../releases/latest`), using the token as a Bearer header if available
+4) Fetch the release metadata from the GitHub API, using the token as a Bearer header if available:
+   - Default: latest stable release (`api.github.com/repos/.../releases/latest`)
+   - With `--prerelease` (shell) / `-Prerelease` (PowerShell): newest release overall including prereleases, via the releases list endpoint (`api.github.com/repos/.../releases?per_page=1`), taking the first (newest) entry
 
 5) Resolve the archive filename from the release metadata based on the detected os-arch