diff --git a/Library/.rubocop.yml b/Library/.rubocop.yml
index 819723b411..01a6d8819b 100644
--- a/Library/.rubocop.yml
+++ b/Library/.rubocop.yml
@@ -15,8 +15,7 @@ AllCops:
   TargetRubyVersion: 3.1
   NewCops: enable
   Include:
-    # FIXME: https://github.com/rubocop/rubocop/issues/12695
-    - "Homebrew/**/*.rbi"
+    - "**/*.rbi"
   Exclude:
     - "Homebrew/sorbet/rbi/{dsl,gems}/**/*.rbi"
     - "Homebrew/sorbet/rbi/parlour.rbi"
@@ -228,8 +227,6 @@ RSpec:
 # Intentionally disabled as it doesn't fit with our code style.
 RSpec/AnyInstance:
   Enabled: false
-RSpec/DescribeClass:
-  Enabled: false
 RSpec/SpecFilePathFormat:
   Enabled: false
 RSpec/StubbedMock:
diff --git a/Library/Homebrew/test/api/internal_tap_json/formula_spec.rb b/Library/Homebrew/test/api/internal_tap_json/formula_spec.rb
index a6347e1806..b6a495922c 100644
--- a/Library/Homebrew/test/api/internal_tap_json/formula_spec.rb
+++ b/Library/Homebrew/test/api/internal_tap_json/formula_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-RSpec.describe "Internal Tap JSON -- Formula" do
+RSpec.describe "Internal Tap JSON -- Formula", type: :system do
   include FileUtils
 
   let(:internal_tap_json) { File.read(TEST_FIXTURE_DIR/"internal_tap_json/homebrew-core.json").chomp }
diff --git a/Library/Homebrew/test/cask/conflicts_with_spec.rb b/Library/Homebrew/test/cask/conflicts_with_spec.rb
deleted file mode 100644
index 329a10e66a..0000000000
--- a/Library/Homebrew/test/cask/conflicts_with_spec.rb
+++ /dev/null
@@ -1,25 +0,0 @@
-# frozen_string_literal: true
-
-RSpec.describe "conflicts_with", :cask do
-  describe "conflicts_with cask" do
-    let(:local_caffeine) do
-      Cask::CaskLoader.load(cask_path("local-caffeine"))
-    end
-
-    let(:with_conflicts_with) do
-      Cask::CaskLoader.load(cask_path("with-conflicts-with"))
-    end
-
-    it "installs the dependency of a Cask and the Cask itself" do
-      Cask::Installer.new(local_caffeine).install
-
-      expect(local_caffeine).to be_installed
-
-      expect do
-        Cask::Installer.new(with_conflicts_with).install
-      end.to raise_error(Cask::CaskConflictError, "Cask 'with-conflicts-with' conflicts with 'local-caffeine'.")
-
-      expect(with_conflicts_with).not_to be_installed
-    end
-  end
-end
diff --git a/Library/Homebrew/test/cask/depends_on_spec.rb b/Library/Homebrew/test/cask/depends_on_spec.rb
index dfb444abc5..c2f0373ddb 100644
--- a/Library/Homebrew/test/cask/depends_on_spec.rb
+++ b/Library/Homebrew/test/cask/depends_on_spec.rb
@@ -2,7 +2,9 @@
 
 # TODO: this test should be named after the corresponding class, once
 #       that class is abstracted from installer.rb
+# rubocop:disable RSpec/DescribeClass
 RSpec.describe "Satisfy Dependencies and Requirements", :cask do
+  # rubocop:enable RSpec/DescribeClass
   subject(:install) do
     Cask::Installer.new(cask).install
   end
diff --git a/Library/Homebrew/test/cask/dsl_spec.rb b/Library/Homebrew/test/cask/dsl_spec.rb
index 3cc70983d1..891c33a3a1 100644
--- a/Library/Homebrew/test/cask/dsl_spec.rb
+++ b/Library/Homebrew/test/cask/dsl_spec.rb
@@ -444,6 +444,28 @@ RSpec.describe Cask::DSL, :cask do
     end
   end
 
+  describe "conflicts_with cask" do
+    let(:local_caffeine) do
+      Cask::CaskLoader.load(cask_path("local-caffeine"))
+    end
+
+    let(:with_conflicts_with) do
+      Cask::CaskLoader.load(cask_path("with-conflicts-with"))
+    end
+
+    it "installs the dependency of a Cask and the Cask itself" do
+      Cask::Installer.new(local_caffeine).install
+
+      expect(local_caffeine).to be_installed
+
+      expect do
+        Cask::Installer.new(with_conflicts_with).install
+      end.to raise_error(Cask::CaskConflictError, "Cask 'with-conflicts-with' conflicts with 'local-caffeine'.")
+
+      expect(with_conflicts_with).not_to be_installed
+    end
+  end
+
   describe "conflicts_with stanza" do
     context "when valid" do
       let(:token) { "with-conflicts-with" }
diff --git a/Library/Homebrew/test/cmd/--version_spec.rb b/Library/Homebrew/test/cmd/--version_spec.rb
index 75cf483a52..772fd5348c 100644
--- a/Library/Homebrew/test/cmd/--version_spec.rb
+++ b/Library/Homebrew/test/cmd/--version_spec.rb
@@ -1,8 +1,6 @@
 # frozen_string_literal: true
 
-require "cmd/shared_examples/args_parse"
-
-RSpec.describe "brew --version" do
+RSpec.describe "brew --version", type: :system do
   it "prints the Homebrew's version", :integration_test do
     expect { brew_sh "--version" }
       .to output(/^Homebrew #{Regexp.escape(HOMEBREW_VERSION)}\n/o).to_stdout
diff --git a/Library/Homebrew/test/cmd/custom-external-command_spec.rb b/Library/Homebrew/test/cmd/custom-external-command_spec.rb
index d16bb4ad54..cabfc5efd1 100644
--- a/Library/Homebrew/test/cmd/custom-external-command_spec.rb
+++ b/Library/Homebrew/test/cmd/custom-external-command_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-RSpec.describe "brew custom-external-command", :integration_test do
+RSpec.describe "brew custom-external-command", :integration_test, type: :system do
   it "is supported" do
     mktmpdir do |path|
       cmd = "custom-external-command-#{rand}"
diff --git a/Library/Homebrew/test/extend/kernel_spec.rb b/Library/Homebrew/test/extend/kernel_spec.rb
index eb81687878..200756b4cf 100644
--- a/Library/Homebrew/test/extend/kernel_spec.rb
+++ b/Library/Homebrew/test/extend/kernel_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-RSpec.describe "globally-scoped helper methods" do
+RSpec.describe Kernel do
   let(:dir) { mktmpdir }
 
   def esc(code)
diff --git a/Library/Homebrew/test/global_spec.rb b/Library/Homebrew/test/global_spec.rb
index 76abb380f0..9a7450abd8 100644
--- a/Library/Homebrew/test/global_spec.rb
+++ b/Library/Homebrew/test/global_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-RSpec.describe "brew", :integration_test do
+RSpec.describe Homebrew, :integration_test do
   it "does not invoke `require \"formula\"` at startup" do
     expect { brew "verify-formula-undefined" }
       .to not_to_output.to_stdout
diff --git a/Library/Homebrew/test/os/mac/mach_spec.rb b/Library/Homebrew/test/os/mac/mach_spec.rb
index 4f6da3938f..28d4f1f882 100644
--- a/Library/Homebrew/test/os/mac/mach_spec.rb
+++ b/Library/Homebrew/test/os/mac/mach_spec.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-RSpec.describe "Mach-O" do
+RSpec.describe MachOShim do
   describe "Pathname tests" do
     specify "fat dylib" do
       pn = dylib_path("fat")
diff --git a/Library/Homebrew/test/os/mac/pkgconfig_spec.rb b/Library/Homebrew/test/os/mac/pkgconfig_spec.rb
index 849c17b332..21177c94d6 100644
--- a/Library/Homebrew/test/os/mac/pkgconfig_spec.rb
+++ b/Library/Homebrew/test/os/mac/pkgconfig_spec.rb
@@ -12,7 +12,7 @@
 # Additionally, libffi version detection cannot be performed on systems running Mojave or earlier.
 #
 # For indeterminable cases, consult https://opensource.apple.com for the version used.
-RSpec.describe "pkg-config", :needs_ci do
+RSpec.describe "pkg-config", :needs_ci, type: :system do
   def pc_version(library)
     path = HOMEBREW_LIBRARY_PATH/"os/mac/pkgconfig/#{MacOS.version}/#{library}.pc"
     version = File.foreach(path)
diff --git a/Library/Homebrew/test/patching_spec.rb b/Library/Homebrew/test/patching_spec.rb
index 7ca14c511c..74171d0535 100644
--- a/Library/Homebrew/test/patching_spec.rb
+++ b/Library/Homebrew/test/patching_spec.rb
@@ -2,7 +2,7 @@
 
 require "formula"
 
-RSpec.describe "patching" do
+RSpec.describe "patching", type: :system do
   let(:formula_subclass) do
     Class.new(Formula) do
       # These are defined within an anonymous class to avoid polluting the global namespace.
@@ -229,15 +229,3 @@ RSpec.describe "patching" do
     end.to raise_error(BuildError)
   end
 end
-
-__END__
-diff --git a/libexec/NOOP b/libexec/NOOP
-index bfdda4c..e08d8f4 100755
---- a/libexec/NOOP
-+++ b/libexec/NOOP
-@@ -1,2 +1,2 @@
- #!/bin/bash
--echo NOOP
-\ No newline at end of file
-+echo ABCD
-\ No newline at end of file
diff --git a/Library/Homebrew/test/sorbet/tapioca/config_spec.rb b/Library/Homebrew/test/sorbet/tapioca/config_spec.rb
index 6a1449bc7c..3fb5101618 100644
--- a/Library/Homebrew/test/sorbet/tapioca/config_spec.rb
+++ b/Library/Homebrew/test/sorbet/tapioca/config_spec.rb
@@ -3,7 +3,7 @@
 require "rubygems"
 require "yaml"
 
-RSpec.describe "Tapioca Config" do
+RSpec.describe "Tapioca Config", type: :system do
   let(:config) { YAML.load_file(File.join(__dir__, "../../../sorbet/tapioca/config.yml")) }
 
   it "only excludes dependencies" do