New Cask

SKILL: Adding a New Cask to homebrew-dotnet-sdk-versions

When to use this skill

Use this skill whenever a user asks to:

• Add a new cask / feature band (e.g. "add dotnet-sdk12-0-100")
• Support a new .NET SDK major or minor version that doesn't have a cask yet
• Create a stub cask for a new release band

Repository context

• Repo: https://github.com/isen-ng/homebrew-dotnet-sdk-versions
• Casks live in: Casks/ directory, Ruby .rb files
• Naming convention: dotnet-sdk{MAJOR}-{MINOR}-{FEATURE_HUNDREDS}.rb
  • Examples: dotnet-sdk8-0-400.rb, dotnet-sdk10-0-100.rb, dotnet-sdk11-preview.rb
• The filename and cask name inside the file must match (Homebrew rule)
• Meta casks (e.g. dotnet-sdk8.rb) are auto-generated by auto_meta_updater.py — do NOT hand-edit them
• Preview casks follow the naming dotnet-sdk{MAJOR}-preview.rb

Cask file structure

Universal (x64 + arm64) cask — used for .NET 6+ stable

cask "dotnet-sdk10-0-200" do
  arch arm: "arm64", intel: "x64"

  version "10.0.200,10.0.0"

  sha256_x64 = "????????????????????????????????????????????????????????????????"
  sha256_arm64 = "????????????????????????????????????????????????????????????????"
  url_x64 = "https://builds.dotnet.microsoft.com/dotnet/Sdk/#{version.csv.first}/dotnet-sdk-#{version.csv.first}-osx-x64.pkg"
  url_arm64 = "https://builds.dotnet.microsoft.com/dotnet/Sdk/#{version.csv.first}/dotnet-sdk-#{version.csv.first}-osx-arm64.pkg"
  on_arm do
    sha256 sha256_arm64

    url url_arm64
  end
  on_intel do
    sha256 sha256_x64

    url url_x64
  end

  name ".NET Core SDK #{version.csv.first}"
  desc "This cask follows releases from https://github.com/dotnet/core/tree/master"
  homepage "https://www.microsoft.com/net/core#macos"

  livecheck do
    skip "See https://github.com/isen-ng/homebrew-dotnet-sdk-versions/blob/master/CONTRIBUTING.md#automatic-updates"
  end

  depends_on macos: :monterey

  pkg "dotnet-sdk-#{version.csv.first}-osx-#{arch}.pkg"

  uninstall pkgutil: "com.microsoft.dotnet.dev.#{version.csv.first}.component.osx.#{arch}"

  zap pkgutil: [
        "com.microsoft.dotnet.hostfxr.#{version.csv.second}.component.osx.#{arch}",
        "com.microsoft.dotnet.pack.apphost.#{version.csv.second}.component.osx.#{arch}",
        "com.microsoft.dotnet.sharedframework.Microsoft.NETCore.App.#{version.csv.second}.component.osx.#{arch}",
        "com.microsoft.dotnet.sharedhost.component.osx.#{arch}",
      ],
      trash:   ["~/.dotnet", "~/.nuget", "/etc/paths.d/dotnet", "/etc/paths.d/dotnet-cli-tools"]

  caveats "Uninstalling the official dotnet-sdk casks will remove the shared runtime dependencies, " \
          "so you'll need to reinstall the particular version cask you want from this tap again " \
          "for the `dotnet` command to work again."
end

Intel-only cask — used for .NET 5 and earlier (arm64 is NOT supported)

cask "dotnet-sdk5-0-400" do
  version "5.0.408,5.0.17"
  sha256 "????????????????????????????????????????????????????????????????"

  on_arm do
    FileUtils.ln_sf("/usr/local/share/dotnet/x64/dotnet", "#{HOMEBREW_PREFIX}/bin/dotnetx64")
  end

  url "https://download.visualstudio.microsoft.com/download/pr/<guid>/dotnet-sdk-#{version.csv.first}-osx-x64.pkg"
  name ".NET Core SDK #{version.csv.first}"
  desc "This cask follows releases from https://github.com/dotnet/core/tree/master"
  homepage "https://www.microsoft.com/net/core#macos"

  livecheck do
    skip "See https://github.com/isen-ng/homebrew-dotnet-sdk-versions/blob/master/CONTRIBUTING.md#automatic-updates"
  end

  depends_on macos: :sonoma

  pkg "dotnet-sdk-#{version.csv.first}-osx-x64.pkg"

  uninstall pkgutil: "com.microsoft.dotnet.dev.#{version.csv.first}.component.osx.x64"

  zap pkgutil: [
        "com.microsoft.dotnet.hostfxr.#{version.csv.second}.component.osx.x64",
        "com.microsoft.dotnet.pack.apphost.#{version.csv.second}.component.osx.x64",
        "com.microsoft.dotnet.sharedframework.Microsoft.NETCore.App.#{version.csv.second}.component.osx.x64",
        "com.microsoft.dotnet.sharedhost.component.osx.x64",
      ],
      trash:   ["~/.dotnet", "~/.nuget", "/etc/paths.d/dotnet", "/etc/paths.d/dotnet-cli-tools"]

  caveats "If you are installing this x64 binary on an Apple M1 (arm64) machine, the x64 version of `dotnet`" \
          "command will be symlinked as `dotnetx64`\n\n" \
          "Uninstalling the official dotnet-sdk casks will remove the shared runtime dependencies, " \
          "so you'll need to reinstall the particular version cask you want from this tap again " \
          "for the `dotnet` command to work again."
end

Preview cask — used for preview/RC releases

cask "dotnet-sdk11-preview" do
  arch arm: "arm64", intel: "x64"

  version "11.0.100-preview.1.25101.1,11.0.0-preview.1.25103.1"

  sha256_x64 = "????????????????????????????????????????????????????????????????"
  sha256_arm64 = "????????????????????????????????????????????????????????????????"
  url_x64 = "https://builds.dotnet.microsoft.com/dotnet/Sdk/#{version.csv.first}/dotnet-sdk-#{version.csv.first}-osx-x64.pkg"
  url_arm64 = "https://builds.dotnet.microsoft.com/dotnet/Sdk/#{version.csv.first}/dotnet-sdk-#{version.csv.first}-osx-arm64.pkg"

  on_arm do
    sha256 sha256_arm64

    url url_arm64
  end
  on_intel do
    sha256 sha256_x64

    url url_x64
  end

  name ".NET SDK #{version.csv.first}"
  desc "This cask follows releases from https://github.com/dotnet/core/tree/master"
  homepage "https://www.microsoft.com/net/core#macos"

  livecheck do
    skip "See https://github.com/isen-ng/homebrew-dotnet-sdk-versions/blob/master/CONTRIBUTING.md#automatic-updates"
  end

  depends_on macos: :monterey

  pkg "dotnet-sdk-#{version.csv.first}-osx-#{arch}.pkg"

  uninstall pkgutil: "com.microsoft.dotnet.dev.#{version.csv.first}.component.osx.#{arch}"

  zap pkgutil: [
        "com.microsoft.dotnet.hostfxr.#{version.csv.second}.component.osx.#{arch}",
        "com.microsoft.dotnet.pack.apphost.#{version.csv.second}.component.osx.#{arch}",
        "com.microsoft.dotnet.sharedframework.Microsoft.NETCore.App.#{version.csv.second}.component.osx.#{arch}",
        "com.microsoft.dotnet.sharedhost.component.osx.#{arch}",
      ],
      trash:   ["~/.dotnet", "~/.nuget", "/etc/paths.d/dotnet", "/etc/paths.d/dotnet-cli-tools"]

  caveats "Uninstalling the official dotnet-sdk casks will remove the shared runtime dependencies, " \
          "so you'll need to reinstall the particular version cask you want from this tap again " \
          "for the `dotnet` command to work again."
end

Step-by-step: how to add a new cask

1. Determine the cask name

Use the naming convention dotnet-sdk{MAJOR}-{MINOR}-{FEATURE_HUNDREDS}:

• dotnet-sdk10-0-200 → covers SDK 10.0.2xx
• dotnet-sdk11-0-100 → covers SDK 11.0.1xx
• Preview: dotnet-sdk11-preview

2. Determine arm64 support

• .NET 6+ → use the universal cask template (both x64 and arm64)
• .NET 5 and earlier → use the Intel-only cask template

3. Determine the depends_on macos: value

Copy from an adjacent existing cask for the same .NET generation:

• .NET 8: :big_sur
• .NET 9, 10, 11+: :monterey

4. Create the stub file

Create Casks/dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}.rb with:

• Correct cask name matching the filename
• A placeholder version like "{MAJOR}.{MINOR}.{FEATURE}00,{MAJOR}.0.0" (auto_updater will fill the real value)
• Placeholder sha256 values ("????????????????..." — auto_updater is forced to compute real values)
• For .NET 6+: use builds.dotnet.microsoft.com URL pattern (no GUID needed — the URL is predictable)
• For .NET 5 and earlier: use download.visualstudio.microsoft.com/download/pr/<guid>/... URL pattern with a placeholder GUID
• Correct uninstall and zap pkgutil patterns using version.csv.first and version.csv.second
• Include caveats block

5. Run auto_updater.py in dry-run mode

# dry-run (no --really_push) — updates all casks including the new one
./auto_updater.py

This will:

• Download releases.json for the major.minor band from github.com/dotnet/core
• Find the latest patch release for the feature band
• Download the .pkg, verify SHA-512, compute SHA-256
• Rewrite the cask file with correct version, sha256, and url

6. Validate the cask locally

brew tap isen-ng/dotnet-sdk-versions $PWD
brew style Casks/dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}.rb
brew audit --cask dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}

7. Open the PR

If you are the repo owner (pushing directly to origin):

git checkout -b new-cask/dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}
git add Casks/dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}.rb
git commit -m "Add support for dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}"
git push origin new-cask/dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}

If you are an external contributor (pushing to your fork):

git checkout -b new-cask/dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}
git add Casks/dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}.rb
git commit -m "Add support for dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}"
git push fork new-cask/dotnet-sdk{MAJOR}-{MINOR}-{FEATURE}

Then open a PR from that branch into master.

Key rules and gotchas

• Never use placeholder sha256 that passes validation — use "????????????????..." so auto_updater.py is forced to compute the real value.
• The version field has two CSV parts: "SDK_VERSION,RUNTIME_VERSION". auto_updater.py fills both.
• URL must contain #{version.csv.first} interpolation to satisfy brew audit.
• For .NET 6+, the URL uses builds.dotnet.microsoft.com with no GUID: https://builds.dotnet.microsoft.com/dotnet/Sdk/#{version.csv.first}/dotnet-sdk-#{version.csv.first}-osx-{arch}.pkg. Do NOT use the old download.visualstudio.microsoft.com/download/pr/<guid>/... format.
• Meta casks (dotnet-sdk8.rb) are auto-generated — never create or edit them manually. Run auto_meta_updater.py after merging the new versioned cask.
• depends_on macos — copy from an adjacent existing cask for the same .NET generation to match the minimum macOS requirement.
• uninstall pkgutil: takes a single string, not an array.
• zap must include both pkgutil: array and trash: array.
• pkgutil identifiers follow the pattern com.microsoft.dotnet.dev.{sdk_version}.component.osx.{arch} — double-check against the actual .pkg installer if unsure.
• For preview casks, the version string includes pre-release labels: "11.0.100-preview.1.25101.1,11.0.0-preview.1.25103.1". The PreviewSdkVersion class in auto_updater.py handles this format.
• name field: use ".NET SDK" for .NET 11+ preview casks; use ".NET Core SDK" for stable/older casks.