Adopt the standard C# repository layout

.editorconfig

@@ -0,0 +1,17 @@
+root = true
+
+[*]
+charset = utf-8
+insert_final_newline = true
+trim_trailing_whitespace = true
+indent_style = space
+indent_size = 4
+
+[*.cs]
+csharp_style_namespace_declarations = file_scoped:suggestion
+
+[*.{csproj,props,targets,wxs,sln,json,yaml,yml}]
+indent_size = 2
+
+[*.md]
+trim_trailing_whitespace = false

.gitattributes

@@ -0,0 +1,11 @@
+# Normalize line endings; keep Windows script types CRLF on checkout.
+* text=auto
+
+*.ps1 text eol=crlf
+*.cmd text eol=crlf
+*.bat text eol=crlf
+*.sh  text eol=lf
+
+*.exe binary
+*.msi binary
+*.zip binary

.github/workflows/ci.yml

@@ -0,0 +1,24 @@
+name: CI
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  test:
+    runs-on: windows-latest
+    timeout-minutes: 30
+    steps:
+      - uses: actions/checkout@v5
+      - uses: actions/setup-dotnet@v4
+        with:
+          global-json-file: global.json
+      - run: dotnet build rbmanager.sln
+      # The hosted image has VS with MSVC, so the RequiresVS and Publish
+      # suites run for real instead of skipping.
+      - run: dotnet test rbmanager.sln --no-build

.gitignore

@@ -3,9 +3,5 @@ dist/
 *.msi
 *.wixpdb
 *.cab
-rbmanager/bin/
-rbmanager/obj/
-rbmanager/publish/
-rbmanager.Tests/bin/
-rbmanager.Tests/obj/
+artifacts/
 TestResults/

Directory.Build.props

@@ -0,0 +1,14 @@
+<Project>
+  <PropertyGroup>
+    <!-- Centralize all build output under artifacts/ (SDK 8+ layout)
+         instead of per-project bin/ and obj/. -->
+    <UseArtifactsOutput>true</UseArtifactsOutput>
+  </PropertyGroup>
+
+  <!-- WixToolset.Sdk does not implement the artifacts output layout,
+       so route .wixproj output there explicitly. -->
+  <PropertyGroup Condition="'$(MSBuildProjectExtension)' == '.wixproj'">
+    <BaseOutputPath>$(MSBuildThisFileDirectory)artifacts\bin\$(MSBuildProjectName)\</BaseOutputPath>
+    <BaseIntermediateOutputPath>$(MSBuildThisFileDirectory)artifacts\obj\$(MSBuildProjectName)\</BaseIntermediateOutputPath>
+  </PropertyGroup>
+</Project>

README.md

@@ -21,48 +21,75 @@ after the language (`%LOCALAPPDATA%\Ruby`, like `%LocalAppData%\Python`)
 rather than after the tool. rbmanager remains the product name.
 
 ```
-rb setup               copy rb itself onto PATH
-rb install <zip|url>   install a ruby binary package
-rb list                list installed rubies
-rb use <version>       switch the active ruby
-rb uninstall <version> remove an installed ruby
+rb setup [--yes]        copy rb onto PATH and set up the VC++ runtime
+rb install <zip|url>    install a ruby binary package
+rb list                 list installed rubies
+rb use <version>        switch the active ruby
+rb uninstall <version>  remove an installed ruby
+rb enable [shell]       print C++ build env to eval (cmd|powershell)
+rb exec <command...>    run a command with the C++ build env applied
 ```
 
 rb is a bare exe; `setup` copies it to
 `%LOCALAPPDATA%\Ruby\bin` and puts that directory on the user PATH,
-which stands in for an installer until a winget manifest exists.
+which stands in for an installer until the winget and MSI channels
+ship. It also checks for the VC++ 2015-2022 redistributable the
+official mswin packages depend on, and offers to download and install
+it (signature-verified, elevated); `--yes` skips the consent prompt.
+
+`enable` and `exec` are the `ridk enable` equivalent for building
+C extension gems with MSVC; see
+[docs/devkit-enable.md](docs/devkit-enable.md).
 
 The active ruby is exposed through an NTFS directory junction
 `%LOCALAPPDATA%\Ruby\current`, and `install` appends
 `%LOCALAPPDATA%\Ruby\current\bin` to the user PATH once; switching
 versions only re-points the junction. Junctions rather than symbolic
 links because they need no privilege and no Developer Mode.
 
-Build (requires the .NET 8 SDK and MSVC link.exe):
+## Build and test
+
+Regular development needs only the .NET 8 SDK (the feature band is
+pinned by `global.json`):
+
+```
+dotnet build rbmanager.sln
+dotnet test rbmanager.sln
+```
+
+Suites that need more than the SDK (Visual Studio, network access)
+skip themselves when the environment lacks it; the category filters
+for running them selectively are listed in
+[docs/test-plan.md](docs/test-plan.md). CI
+(`.github/workflows/ci.yml`) runs the same build and the full suite
+on windows-latest, where VS is present.
+
+Publishing the shipping rb.exe additionally requires MSVC link.exe:
 
 ```
-dotnet publish rbmanager -r win-x64 -c Release -o rbmanager\publish
+dotnet publish src\rbmanager -r win-x64 -c Release -o artifacts\publish\rbmanager
 ```
 
-This produces a self-contained NativeAOT `rb.exe` (~5 MB) with no
+This produces a self-contained NativeAOT `rb.exe` (~6 MB) with no
 runtime dependency.
 
 ## rbmanager MSI
 
 For channels that want a real installer instead of the bare exe,
 `build-installer.ps1` wraps rb.exe in a per-user MSI
-(`src/rbmanager.wxs`, WiX v5):
+(`src/rbmanager.Installer/`, a WiX v5 SDK-style project):
 
 ```
-.\build-installer.ps1 -Validate
+.\build-installer.ps1
 ```
 
 The MSI installs `rb.exe` into `%LOCALAPPDATA%\Ruby\bin` and puts that
 directory on the user PATH, producing exactly the layout `rb setup`
 creates, and removes both again on uninstall. rbmanager is a single MSI
 product line; see [docs/upgrade-code.md](docs/upgrade-code.md). WiX
-5.0.2 is pinned as a dotnet local tool in `.config/dotnet-tools.json`.
-The output is unsigned; code signing is tracked separately.
+5.0.2 comes in through the `WixToolset.Sdk` NuGet package, and ICE
+validation runs as part of the build. The output is unsigned; code
+signing is tracked separately.
 
 An earlier iteration packaged each Ruby version as its own MSI. That
 direction was dropped in favor of rbmanager; see the git history for
@@ -85,8 +112,13 @@ failure modes all degrade to the previous behavior.
 
 ## Layout
 
-- `rbmanager/` — the version manager (C#, NativeAOT)
+- `src/rbmanager/` — the version manager (C#, NativeAOT)
+- `tests/rbmanager.Tests/` — the xUnit test suite
 - `overlay/` — files layered onto every installed runtime
-- `src/rbmanager.wxs`, `build-installer.ps1` — the rbmanager MSI
+- `src/rbmanager.Installer/`, `build-installer.ps1` — the rbmanager MSI
+- `winget/` — draft winget manifests
 - `docs/` — design notes
 - `tools/query.ps1` — dump MSI tables via the WindowsInstaller COM API
+
+Build output goes to `artifacts/` (`UseArtifactsOutput` in
+`Directory.Build.props`), never into the project directories.

build-installer.ps1

@@ -3,19 +3,19 @@
   Build the rbmanager MSI (rb.exe installer).
 
 .DESCRIPTION
-  Publishes rb.exe with NativeAOT and compiles src/rbmanager.wxs with
-  WiX v5 into a per-user MSI under dist/. Code signing is a separate,
-  later step; the output is unsigned.
+  Publishes rb.exe with NativeAOT and builds src/rbmanager.Installer
+  (WiX v5, SDK-style) into a per-user MSI under dist/. ICE validation
+  runs as part of the build. Code signing is a separate, later step;
+  the output is unsigned.
 
 .EXAMPLE
   .\build-installer.ps1
-  .\build-installer.ps1 -Version 0.1.0 -Validate
+  .\build-installer.ps1 -Version 0.1.0
 #>
 param(
   [string]$Version = '0.1.0',
   [ValidateSet('x64', 'arm64')][string]$Arch = 'x64',
   [string]$OutDir = (Join-Path $PSScriptRoot 'dist'),
-  [switch]$Validate,
   [switch]$SkipPublish
 )
 
@@ -25,69 +25,30 @@ if ($Version -notmatch '^\d+\.\d+\.\d+$') {
   throw "Version must be numeric x.y.z for MSI ProductVersion, got '$Version'"
 }
 
-# UUIDv5 derivation; see docs/upgrade-code.md. rbmanager is a single
-# product line, so the arch is not part of its identity.
-$NamespaceGuid = [guid]'E2C11F7E-A84E-4363-A0EB-D0A93E07E3CF'
-
-function New-UuidV5([guid]$Namespace, [string]$Name) {
-  $ns = $Namespace.ToByteArray()
-  # GUID byte layout is little-endian in the first three fields; RFC 4122
-  # hashing requires network byte order.
-  [Array]::Reverse($ns, 0, 4); [Array]::Reverse($ns, 4, 2); [Array]::Reverse($ns, 6, 2)
-  $sha1 = [System.Security.Cryptography.SHA1]::Create()
-  try {
-    $hash = $sha1.ComputeHash($ns + [System.Text.Encoding]::UTF8.GetBytes($Name))
-  } finally {
-    $sha1.Dispose()
-  }
-  $b = $hash[0..15]
-  $b[6] = ($b[6] -band 0x0F) -bor 0x50   # version 5
-  $b[8] = ($b[8] -band 0x3F) -bor 0x80   # RFC 4122 variant
-  [Array]::Reverse($b, 0, 4); [Array]::Reverse($b, 4, 2); [Array]::Reverse($b, 6, 2)
-  [guid][byte[]]$b
-}
-
-$upgradeCode = New-UuidV5 $NamespaceGuid 'ruby-windows-installer:upgrade-code:rbmanager'
-$pathGuid = New-UuidV5 $NamespaceGuid 'ruby-windows-installer:path-component:rbmanager:perUser'
-
 $dotnet = Get-Command dotnet -ErrorAction SilentlyContinue
 $dotnet = if ($dotnet) { $dotnet.Source } else { 'C:\Program Files\dotnet\dotnet.exe' }
 
-$publishDir = Join-Path $PSScriptRoot 'rbmanager\publish'
+$publishDir = Join-Path $PSScriptRoot 'artifacts\publish\rbmanager'
 $rbExe = Join-Path $publishDir 'rb.exe'
 
 Push-Location $PSScriptRoot
 try {
   if (-not $SkipPublish) {
     Write-Host "Publishing rb.exe ($Arch) ..."
-    & $dotnet publish rbmanager -r "win-$Arch" -c Release -o $publishDir
+    & $dotnet publish src\rbmanager -r "win-$Arch" -c Release -o $publishDir
     if ($LASTEXITCODE -ne 0) { throw "dotnet publish failed" }
   }
   if (-not (Test-Path $rbExe)) { throw "$rbExe not found" }
 
-  & $dotnet tool restore | Out-Null
-  if ($LASTEXITCODE -ne 0) { throw "dotnet tool restore failed" }
+  Write-Host "Building the MSI ..."
+  & $dotnet build src\rbmanager.Installer -c Release `
+    "-p:ProductVersion=$Version" "-p:InstallerPlatform=$Arch" "-p:RbExe=$rbExe"
+  if ($LASTEXITCODE -ne 0) { throw "MSI build failed" }
 
   New-Item -ItemType Directory -Force $OutDir | Out-Null
   $msi = Join-Path $OutDir "rbmanager-$Version-$Arch.msi"
-
-  Write-Host "Building $msi ..."
-  & $dotnet wix build (Join-Path $PSScriptRoot 'src\rbmanager.wxs') `
-    -arch $Arch `
-    -d "Version=$Version" `
-    -d "UpgradeCode=$upgradeCode" `
-    -d "PathComponentGuid=$pathGuid" `
-    -d "RbExe=$rbExe" `
-    -o $msi
-  if ($LASTEXITCODE -ne 0) { throw "wix build failed" }
-
-  if ($Validate) {
-    Write-Host "Validating $msi ..."
-    # Per-user packages installing into the user profile trip ICE38/ICE64/
-    # ICE91 by design; those rules target per-machine packages.
-    & $dotnet wix msi validate '-sice' 'ICE38' '-sice' 'ICE64' '-sice' 'ICE91' $msi
-    if ($LASTEXITCODE -ne 0) { throw "wix msi validate failed" }
-  }
+  Copy-Item (Join-Path $PSScriptRoot "artifacts\bin\rbmanager.Installer\Release\rbmanager-$Version-$Arch.msi") `
+    $msi -Force
 } finally {
   Pop-Location
 }

docs/devkit-enable.md

@@ -241,7 +241,7 @@ should not depend on it.)
 
 ## Prototype
 
-`rbmanager/Devkit.cs` implements both subcommands, wired into
+`src/rbmanager/Devkit.cs` implements both subcommands, wired into
 `Program.cs`'s dispatch switch as `rb enable [shell]` and
 `rb exec <command...>`. It is ~180 lines, marked as a prototype, and
 covers VS discovery, VsDevCmd activation with env-diffing, the

docs/upgrade-code.md

@@ -14,9 +14,9 @@ requires.
 
 ## Derivation
 
-UpgradeCodes are never allocated by hand. build-installer.ps1 derives
-them as UUIDv5 (RFC 4122, SHA-1) from a fixed namespace GUID and a name
-string:
+UpgradeCodes are never allocated by hand. They are derived as UUIDv5
+(RFC 4122, SHA-1) from a fixed namespace GUID and a name string, and
+baked into `src/rbmanager.Installer/Package.wxs` as constants:
 
     namespace: E2C11F7E-A84E-4363-A0EB-D0A93E07E3CF
     name:      ruby-windows-installer:upgrade-code:rbmanager
@@ -28,16 +28,33 @@ the repository rename and is frozen with the rest. Changing either
 would silently break in-place upgrades, because new packages would stop
 finding the installed ones.
 
-Derived values for reference (reproducible with `New-UuidV5` in
-build-installer.ps1):
+Derived values for reference:
 
-| name | UpgradeCode |
-|------|-------------|
+| name | GUID |
+|------|------|
 | ruby-windows-installer:upgrade-code:rbmanager | CAB95EEE-B5A6-52EA-94B3-B4413CE23855 |
+| ruby-windows-installer:path-component:rbmanager:perUser | F786646B-2533-5C48-AD8F-9CCDD8AE4D16 |
 
-The PATH environment component needs a stable GUID for the same reason:
+The second entry is the PATH environment component, which needs a
+stable GUID for the same reason. Both are reproducible with:
 
-    name: ruby-windows-installer:path-component:rbmanager:perUser
+```powershell
+function New-UuidV5([guid]$Namespace, [string]$Name) {
+  $ns = $Namespace.ToByteArray()
+  # GUID byte layout is little-endian in the first three fields; RFC 4122
+  # hashing requires network byte order.
+  [Array]::Reverse($ns, 0, 4); [Array]::Reverse($ns, 4, 2); [Array]::Reverse($ns, 6, 2)
+  $hash = [System.Security.Cryptography.SHA1]::HashData(
+    $ns + [System.Text.Encoding]::UTF8.GetBytes($Name))
+  $b = $hash[0..15]
+  $b[6] = ($b[6] -band 0x0F) -bor 0x50   # version 5
+  $b[8] = ($b[8] -band 0x3F) -bor 0x80   # RFC 4122 variant
+  [Array]::Reverse($b, 0, 4); [Array]::Reverse($b, 4, 2); [Array]::Reverse($b, 6, 2)
+  [guid][byte[]]$b
+}
+New-UuidV5 'E2C11F7E-A84E-4363-A0EB-D0A93E07E3CF' `
+  'ruby-windows-installer:upgrade-code:rbmanager'
+```
 
 The retired per-version Ruby MSI used the same scheme with one product
 line per (series, arch) pair; its name formats and derived codes are in

global.json

@@ -0,0 +1,6 @@
+{
+  "sdk": {
+    "version": "8.0.400",
+    "rollForward": "latestFeature"
+  }
+}