diff --git a/Library/Homebrew/cask/cask_loader.rb b/Library/Homebrew/cask/cask_loader.rb
index 751e1d3009..1f6a7a285c 100644
--- a/Library/Homebrew/cask/cask_loader.rb
+++ b/Library/Homebrew/cask/cask_loader.rb
@@ -438,7 +438,7 @@ module Cask
     end
 
     def self.default_path(token)
-      Tap.default_cask_tap.cask_dir/"#{token.to_s.downcase}.rb"
+      CoreCaskTap.instance.cask_dir/"#{token.to_s.downcase}.rb"
     end
 
     def self.tap_paths(token, warn: true)
diff --git a/Library/Homebrew/cmd/install.rb b/Library/Homebrew/cmd/install.rb
index 33d911d75d..5139671a40 100644
--- a/Library/Homebrew/cmd/install.rb
+++ b/Library/Homebrew/cmd/install.rb
@@ -197,7 +197,11 @@ module Homebrew
       formulae, casks = args.named.to_formulae_and_casks
                             .partition { |formula_or_cask| formula_or_cask.is_a?(Formula) }
     rescue FormulaOrCaskUnavailableError, Cask::CaskUnavailableError
-      retry if Tap.install_default_cask_tap_if_necessary(force: args.cask?)
+      cask_tap = CoreCaskTap.instance
+      if !cask_tap.installed? && (args.cask? || Tap.untapped_official_taps.exclude?(cask_tap.name))
+        cask_tap.ensure_installed!
+        retry if cask_tap.installed?
+      end
 
       raise
     end
diff --git a/Library/Homebrew/cmd/update-report.rb b/Library/Homebrew/cmd/update-report.rb
index ef58ff4c58..f568f61c54 100644
--- a/Library/Homebrew/cmd/update-report.rb
+++ b/Library/Homebrew/cmd/update-report.rb
@@ -149,7 +149,7 @@ module Homebrew
     updated_taps = []
     Tap.each do |tap|
       next if !tap.git? || tap.git_repo.origin_url.nil?
-      next if (tap.core_tap? || tap == "homebrew/cask") && !Homebrew::EnvConfig.no_install_from_api?
+      next if (tap.core_tap? || tap.core_cask_tap?) && !Homebrew::EnvConfig.no_install_from_api?
 
       if ENV["HOMEBREW_MIGRATE_LINUXBREW_FORMULAE"].present? && tap.core_tap? &&
          Settings.read("linuxbrewmigrated") != "true"
@@ -193,7 +193,7 @@ module Homebrew
     unless Homebrew::EnvConfig.no_install_from_api?
       api_cache = Homebrew::API::HOMEBREW_CACHE_API
       core_tap = CoreTap.instance
-      cask_tap = Tap.fetch("homebrew/cask")
+      cask_tap = CoreCaskTap.instance
       [
         [:formula, core_tap, core_tap.formula_dir],
         [:cask,    cask_tap, cask_tap.cask_dir],
@@ -402,7 +402,7 @@ module Homebrew
     return if (HOMEBREW_PREFIX/".homebrewdocker").exist?
 
     core_tap = CoreTap.instance
-    cask_tap = Tap.default_cask_tap
+    cask_tap = CoreCaskTap.instance
     return if !core_tap.installed? && !cask_tap.installed?
 
     puts "Installing from the API is now the default behaviour!"
@@ -504,7 +504,7 @@ class Reporter
       new_name = tap.cask_renames[old_name]
       next unless new_name
 
-      new_full_name = if tap.name == "homebrew/cask"
+      new_full_name = if tap.core_cask_tap?
         new_name
       else
         "#{tap}/#{new_name}"
@@ -518,7 +518,7 @@ class Reporter
       old_name = tap.cask_renames.key(new_name)
       next unless old_name
 
-      old_full_name = if tap.name == "homebrew/cask"
+      old_full_name = if tap.core_cask_tap?
         old_name
       else
         "#{tap}/#{old_name}"
diff --git a/Library/Homebrew/dev-cmd/generate-cask-api.rb b/Library/Homebrew/dev-cmd/generate-cask-api.rb
index 1bbd987fcf..24f0816fad 100644
--- a/Library/Homebrew/dev-cmd/generate-cask-api.rb
+++ b/Library/Homebrew/dev-cmd/generate-cask-api.rb
@@ -42,7 +42,7 @@ module Homebrew
   def generate_cask_api
     args = generate_cask_api_args.parse
 
-    tap = Tap.default_cask_tap
+    tap = CoreCaskTap.instance
     raise TapUnavailableError, tap.name unless tap.installed?
 
     unless args.dry_run?
diff --git a/Library/Homebrew/diagnostic.rb b/Library/Homebrew/diagnostic.rb
index 4d888797b7..41de599b59 100644
--- a/Library/Homebrew/diagnostic.rb
+++ b/Library/Homebrew/diagnostic.rb
@@ -531,7 +531,7 @@ module Homebrew
       end
 
       def check_casktap_integrity
-        default_cask_tap = Tap.default_cask_tap
+        default_cask_tap = CoreCaskTap.instance
         return unless default_cask_tap.installed?
 
         broken_tap(default_cask_tap) || examine_git_origin(default_cask_tap.git_repo, default_cask_tap.remote)
@@ -861,7 +861,7 @@ module Homebrew
         return if Homebrew::EnvConfig.no_install_from_api?
         return if Homebrew::Settings.read("devcmdrun") == "true"
 
-        cask_tap = Tap.fetch("homebrew", "cask")
+        cask_tap = CoreCaskTap.instance
         return unless cask_tap.installed?
 
         <<~EOS
@@ -921,7 +921,7 @@ module Homebrew
       end
 
       def check_cask_taps
-        default_cask_tap = Tap.default_cask_tap
+        default_cask_tap = CoreCaskTap.instance
         alt_taps = Tap.select { |t| t.cask_dir.exist? && t != default_cask_tap }
 
         error_tap_paths = []
diff --git a/Library/Homebrew/extend/os/mac/tap.rb b/Library/Homebrew/extend/os/mac/tap.rb
index 97abb1a3fe..8d9bace415 100644
--- a/Library/Homebrew/extend/os/mac/tap.rb
+++ b/Library/Homebrew/extend/os/mac/tap.rb
@@ -3,12 +3,15 @@
 
 class Tap
   def self.install_default_cask_tap_if_necessary(force: false)
-    return false if default_cask_tap.installed?
+    odeprecated "Tap.install_default_cask_tap_if_necessary", "CoreCaskTap.ensure_installed!"
+
+    cask_tap = CoreCaskTap.instance
+    return false if cask_tap.installed?
     return false unless Homebrew::EnvConfig.no_install_from_api?
     return false if Homebrew::EnvConfig.automatically_set_no_install_from_api?
-    return false if !force && Tap.untapped_official_taps.include?(default_cask_tap.name)
+    return false if !force && Tap.untapped_official_taps.include?(cask_tap.name)
 
-    default_cask_tap.install
+    cask_tap.install
     true
   end
 end
diff --git a/Library/Homebrew/tap.rb b/Library/Homebrew/tap.rb
index 6988916b33..b0196c0176 100644
--- a/Library/Homebrew/tap.rb
+++ b/Library/Homebrew/tap.rb
@@ -52,6 +52,7 @@ class Tap
     repo = repo.sub(HOMEBREW_OFFICIAL_REPO_PREFIXES_REGEX, "")
 
     return CoreTap.instance if ["Homebrew", "Linuxbrew"].include?(user) && ["core", "homebrew"].include?(repo)
+    return CoreCaskTap.instance if user == "Homebrew" && repo == "cask"
 
     cache_key = "#{user}/#{repo}".downcase
     cache.fetch(cache_key) { |key| cache[key] = Tap.new(user, repo) }
@@ -64,13 +65,17 @@ class Tap
     fetch(match[:user], match[:repo])
   end
 
-  sig { returns(T.attached_class) }
+  sig { returns(CoreCaskTap) }
   def self.default_cask_tap
-    @default_cask_tap ||= fetch("Homebrew", "cask")
+    odeprecated "Tap.default_cask_tap", "CoreCaskTap.instance"
+
+    CoreCaskTap.instance
   end
 
   sig { params(force: T::Boolean).returns(T::Boolean) }
   def self.install_default_cask_tap_if_necessary(force: false)
+    odeprecated "Tap.install_default_cask_tap_if_necessary", "CoreCaskTap.ensure_installed!"
+
     false
   end
 
@@ -122,6 +127,7 @@ class Tap
     @cask_dir = nil
     @command_dir = nil
     @formula_files = nil
+    @cask_files = nil
     @alias_dir = nil
     @alias_files = nil
     @aliases = nil
@@ -138,6 +144,13 @@ class Tap
     remove_instance_variable(:@private) if instance_variable_defined?(:@private)
   end
 
+  sig { void }
+  def ensure_installed!
+    return if installed?
+
+    install
+  end
+
   # The remote path to this {Tap}.
   # e.g. `https://github.com/user/homebrew-repo`
   def remote
@@ -245,6 +258,12 @@ class Tap
     false
   end
 
+  # @private
+  sig { returns(T::Boolean) }
+  def core_cask_tap?
+    false
+  end
+
   # Install this {Tap}.
   #
   # @param clone_target [String] If passed, it will be used as the clone remote.
@@ -299,7 +318,7 @@ class Tap
       args << "-q" if quiet
       path.cd { safe_system "git", *args }
       return
-    elsif (core_tap? || name == "homebrew/cask") && !Homebrew::EnvConfig.no_install_from_api? && !force
+    elsif (core_tap? || core_cask_tap?) && !Homebrew::EnvConfig.no_install_from_api? && !force
       # odeprecated: move to odie in the next minor release. This may break some CI so we should give notice.
       opoo "Tapping #{name} is no longer typically necessary.\n" \
            "Add #{Formatter.option("--force")} if you are sure you need one."
@@ -553,13 +572,18 @@ class Tap
   sig { params(tap: Tap).returns(T::Hash[String, Pathname]) }
   def self.cask_files_by_name(tap)
     cache_key = "cask_files_by_name_#{tap}"
-
     cache.fetch(cache_key) do |key|
-      cache[key] = tap.cask_files.each_with_object({}) do |file, hash|
-        # If there's more than one file with the same basename: intentionally
-        # ignore the later ones here.
-        hash[file.basename.to_s] ||= file
-      end
+      cache[key] = tap.cask_files_by_name
+    end
+  end
+
+  # @private
+  sig { returns(T::Hash[String, Pathname]) }
+  def cask_files_by_name
+    cask_files.each_with_object({}) do |file, hash|
+      # If there's more than one file with the same basename: intentionally
+      # ignore the later ones here.
+      hash[file.basename.to_s] ||= file
     end
   end
 
@@ -696,9 +720,7 @@ class Tap
   # Hash with tap cask renames.
   sig { returns(T::Hash[String, String]) }
   def cask_renames
-    @cask_renames ||= if name == "homebrew/cask" && !Homebrew::EnvConfig.no_install_from_api?
-      Homebrew::API::Cask.all_renames
-    elsif (rename_file = path/HOMEBREW_TAP_CASK_RENAMES_FILE).file?
+    @cask_renames ||= if (rename_file = path/HOMEBREW_TAP_CASK_RENAMES_FILE).file?
       JSON.parse(rename_file.read)
     else
       {}
@@ -718,11 +740,7 @@ class Tap
   # Hash with tap migrations.
   sig { returns(Hash) }
   def tap_migrations
-    @tap_migrations ||= if name == "homebrew/cask" && !Homebrew::EnvConfig.no_install_from_api?
-      migrations, = Homebrew::API.fetch_json_api_file "cask_tap_migrations.jws.json",
-                                                      stale_seconds: TAP_MIGRATIONS_STALE_SECONDS
-      migrations
-    elsif (migration_file = path/HOMEBREW_TAP_MIGRATIONS_FILE).file?
+    @tap_migrations ||= if (migration_file = path/HOMEBREW_TAP_MIGRATIONS_FILE).file?
       JSON.parse(migration_file.read)
     else
       {}
@@ -749,9 +767,7 @@ class Tap
   # @private
   sig { returns(T::Boolean) }
   def should_report_analytics?
-    return !Homebrew::EnvConfig.no_install_from_api? && official? unless installed?
-
-    !private?
+    installed? && !private?
   end
 
   sig { params(other: T.nilable(T.any(String, Tap))).returns(T::Boolean) }
@@ -867,29 +883,51 @@ class Tap
   end
 end
 
+class AbstractCoreTap < Tap
+  extend T::Helpers
+
+  abstract!
+
+  sig { returns(T.attached_class) }
+  def self.instance
+    @instance ||= T.unsafe(self).new
+  end
+
+  sig { override.void }
+  def ensure_installed!
+    return unless Homebrew::EnvConfig.no_install_from_api?
+    return if Homebrew::EnvConfig.automatically_set_no_install_from_api?
+
+    super
+  end
+
+  sig { void }
+  def self.ensure_installed!
+    instance.ensure_installed!
+  end
+
+  # @private
+  sig { override.returns(T::Boolean) }
+  def should_report_analytics?
+    return super if Homebrew::EnvConfig.no_install_from_api?
+
+    true
+  end
+end
+
 # A specialized {Tap} class for the core formulae.
-class CoreTap < Tap
+class CoreTap < AbstractCoreTap
   # @private
   sig { void }
   def initialize
     super "Homebrew", "core"
   end
 
-  sig { returns(CoreTap) }
-  def self.instance
-    @instance ||= new
-  end
-
-  sig { void }
-  def self.ensure_installed!
-    return if instance.installed?
-    return unless Homebrew::EnvConfig.no_install_from_api?
-    return if Homebrew::EnvConfig.automatically_set_no_install_from_api?
-
-    # Tests override homebrew-core locations and we don't want to auto-tap in them.
+  sig { override.void }
+  def ensure_installed!
     return if ENV["HOMEBREW_TESTS"]
 
-    instance.install
+    super
   end
 
   sig { returns(String) }
@@ -1046,20 +1084,74 @@ class CoreTap < Tap
   def formula_files_by_name
     return super if Homebrew::EnvConfig.no_install_from_api?
 
-    formula_names.each_with_object({}) do |name, hash|
+    Homebrew::API::Formula.all_formulae.each_with_object({}) do |item, hash|
+      name, formula_hash = item
       # If there's more than one file with the same basename: intentionally
       # ignore the later ones here.
-      hash[name] ||= sharded_formula_path(name)
+      hash[name] ||= path/formula_hash["ruby_source_path"]
+    end
+  end
+end
+
+# A specialized {Tap} class for homebrew-cask.
+class CoreCaskTap < AbstractCoreTap
+  # @private
+  sig { void }
+  def initialize
+    super "Homebrew", "cask"
+  end
+
+  # @private
+  sig { override.returns(T::Boolean) }
+  def core_cask_tap?
+    true
+  end
+
+  sig { override.returns(T::Array[Pathname]) }
+  def cask_files
+    return super if Homebrew::EnvConfig.no_install_from_api? || installed?
+
+    raise TapUnavailableError, name
+  end
+
+  sig { override.returns(T::Array[String]) }
+  def cask_tokens
+    return super if Homebrew::EnvConfig.no_install_from_api?
+
+    Homebrew::API::Cask.all_casks.keys
+  end
+
+  # @private
+  sig { override.returns(T::Hash[String, Pathname]) }
+  def cask_files_by_name
+    return super if Homebrew::EnvConfig.no_install_from_api?
+
+    Homebrew::API::Cask.all_casks.each_with_object({}) do |item, hash|
+      name, cask_hash = item
+      # If there's more than one file with the same basename: intentionally
+      # ignore the later ones here.
+      hash[name] ||= path/cask_hash["ruby_source_path"]
     end
   end
 
-  private
+  sig { override.returns(T::Hash[String, String]) }
+  def cask_renames
+    @cask_renames ||= if Homebrew::EnvConfig.no_install_from_api?
+      super
+    else
+      Homebrew::API::Cask.all_renames
+    end
+  end
 
-  # @private
-  sig { params(name: String).returns(Pathname) }
-  def sharded_formula_path(name)
-    # TODO: add sharding logic.
-    formula_dir/"#{name}.rb"
+  sig { override.returns(Hash) }
+  def tap_migrations
+    @tap_migrations ||= if Homebrew::EnvConfig.no_install_from_api?
+      super
+    else
+      migrations, = Homebrew::API.fetch_json_api_file "cask_tap_migrations.jws.json",
+                                                      stale_seconds: TAP_MIGRATIONS_STALE_SECONDS
+      migrations
+    end
   end
 end
 
diff --git a/Library/Homebrew/test/cask/cask_loader/from_tap_loader_spec.rb b/Library/Homebrew/test/cask/cask_loader/from_tap_loader_spec.rb
index 2f1ca8bf77..d352527261 100644
--- a/Library/Homebrew/test/cask/cask_loader/from_tap_loader_spec.rb
+++ b/Library/Homebrew/test/cask/cask_loader/from_tap_loader_spec.rb
@@ -3,10 +3,11 @@
 describe Cask::CaskLoader::FromTapLoader do
   let(:cask_name) { "testball" }
   let(:cask_full_name) { "homebrew/cask/#{cask_name}" }
-  let(:cask_path) { Tap.default_cask_tap.cask_dir/"#{cask_name}.rb" }
+  let(:cask_path) { CoreCaskTap.instance.cask_dir/"#{cask_name}.rb" }
 
   describe "#load" do
     before do
+      CoreCaskTap.instance.clear_cache
       cask_path.parent.mkpath
       cask_path.write <<~RUBY
         cask '#{cask_name}' do
@@ -24,7 +25,7 @@ describe Cask::CaskLoader::FromTapLoader do
     end
 
     context "with sharded Cask directory" do
-      let(:cask_path) { Tap.default_cask_tap.cask_dir/cask_name[0]/"#{cask_name}.rb" }
+      let(:cask_path) { CoreCaskTap.instance.cask_dir/cask_name[0]/"#{cask_name}.rb" }
 
       it "returns a Cask" do
         expect(described_class.new(cask_full_name).load(config: nil)).to be_a(Cask::Cask)
diff --git a/Library/Homebrew/test/cask/cask_spec.rb b/Library/Homebrew/test/cask/cask_spec.rb
index c8071cd408..10f69df402 100644
--- a/Library/Homebrew/test/cask/cask_spec.rb
+++ b/Library/Homebrew/test/cask/cask_spec.rb
@@ -24,7 +24,7 @@ describe Cask::Cask, :cask do
   end
 
   describe "load" do
-    let(:tap_path) { Tap.default_cask_tap.path }
+    let(:tap_path) { CoreCaskTap.instance.path }
     let(:file_dirname) { Pathname.new(__FILE__).dirname }
     let(:relative_tap_path) { tap_path.relative_path_from(file_dirname) }
 
diff --git a/Library/Homebrew/test/diagnostic_checks_spec.rb b/Library/Homebrew/test/diagnostic_checks_spec.rb
index 7d51a90d3b..d04c5d9a52 100644
--- a/Library/Homebrew/test/diagnostic_checks_spec.rb
+++ b/Library/Homebrew/test/diagnostic_checks_spec.rb
@@ -119,7 +119,7 @@ describe Homebrew::Diagnostic::Checks do
     ENV.delete("HOMEBREW_DEVELOPER")
     ENV.delete("HOMEBREW_NO_INSTALL_FROM_API")
 
-    allow(CoreTap).to receive(:installed?).and_return(true)
+    expect_any_instance_of(CoreTap).to receive(:installed?).and_return(true)
 
     expect(checks.check_for_unnecessary_core_tap).to match("You have an unnecessary local Core tap")
   end
@@ -128,9 +128,7 @@ describe Homebrew::Diagnostic::Checks do
     ENV.delete("HOMEBREW_DEVELOPER")
     ENV.delete("HOMEBREW_NO_INSTALL_FROM_API")
 
-    cask_tap = Tap.new("homebrew", "cask")
-    allow(Tap).to receive(:fetch).with("homebrew", "cask").and_return(cask_tap)
-    allow(cask_tap).to receive(:installed?).and_return(true)
+    expect_any_instance_of(CoreCaskTap).to receive(:installed?).and_return(true)
 
     expect(checks.check_for_unnecessary_cask_tap).to match("unnecessary local Cask tap")
   end
diff --git a/Library/Homebrew/test/support/helper/spec/shared_context/homebrew_cask.rb b/Library/Homebrew/test/support/helper/spec/shared_context/homebrew_cask.rb
index c0067277a2..003705110a 100644
--- a/Library/Homebrew/test/support/helper/spec/shared_context/homebrew_cask.rb
+++ b/Library/Homebrew/test/support/helper/spec/shared_context/homebrew_cask.rb
@@ -38,7 +38,7 @@ RSpec.shared_context "Homebrew Cask", :needs_macos do # rubocop:disable RSpec/Co
     begin
       Cask::Config::DEFAULT_DIRS_PATHNAMES.each_value(&:mkpath)
 
-      Tap.default_cask_tap.tap do |tap|
+      CoreCaskTap.instance.tap do |tap|
         FileUtils.mkdir_p tap.path.dirname
         FileUtils.ln_sf TEST_FIXTURE_DIR.join("cask"), tap.path
       end
@@ -52,7 +52,7 @@ RSpec.shared_context "Homebrew Cask", :needs_macos do # rubocop:disable RSpec/Co
     ensure
       FileUtils.rm_rf Cask::Config::DEFAULT_DIRS_PATHNAMES.values
       FileUtils.rm_rf [Cask::Config.new.binarydir, Cask::Caskroom.path, Cask::Cache.path]
-      Tap.default_cask_tap.path.unlink
+      CoreCaskTap.instance.path.unlink
       third_party_tap.path.unlink
       FileUtils.rm_rf third_party_tap.path.parent
     end