diff --git a/Library/Homebrew/Gemfile.lock b/Library/Homebrew/Gemfile.lock
index 549e4251a3..6499d238a7 100644
--- a/Library/Homebrew/Gemfile.lock
+++ b/Library/Homebrew/Gemfile.lock
@@ -11,7 +11,7 @@ GEM
       public_suffix (>= 2.0.2, < 5.0)
     ast (2.4.2)
     bindata (2.4.10)
-    bootsnap (1.12.0)
+    bootsnap (1.13.0)
       msgpack (~> 1.2)
     byebug (11.1.3)
     coderay (1.1.3)
diff --git a/Library/Homebrew/cmd/update.sh b/Library/Homebrew/cmd/update.sh
index 69cb58ccdb..61f7a401b6 100644
--- a/Library/Homebrew/cmd/update.sh
+++ b/Library/Homebrew/cmd/update.sh
@@ -556,6 +556,9 @@ EOS
     [[ -d "${DIR}/.git" ]] || continue
     cd "${DIR}" || continue
 
+    # Git's fsmonitor prevents the release of our locks
+    git config --bool core.fsmonitor false
+
     if ! git config --local --get remote.origin.url &>/dev/null
     then
       opoo "No remote 'origin' in ${DIR}, skipping update!"
diff --git a/Library/Homebrew/extend/on_system.rb b/Library/Homebrew/extend/on_system.rb
index 5ec59cbdfa..a7f7b3744f 100644
--- a/Library/Homebrew/extend/on_system.rb
+++ b/Library/Homebrew/extend/on_system.rb
@@ -15,8 +15,7 @@ module OnSystem
   def arch_condition_met?(arch)
     raise ArgumentError, "Invalid arch condition: #{arch.inspect}" if ARCH_OPTIONS.exclude?(arch)
 
-    current_arch = Homebrew::SimulateSystem.arch || Hardware::CPU.type
-    arch == current_arch
+    arch == Homebrew::SimulateSystem.current_arch
   end
 
   sig { params(os_name: Symbol, or_condition: T.nilable(Symbol)).returns(T::Boolean) }
@@ -26,14 +25,7 @@ module OnSystem
       return true if [:macos, *MacOSVersions::SYMBOLS.keys].include?(os_name)
     end
 
-    if BASE_OS_OPTIONS.include?(os_name)
-      if Homebrew::SimulateSystem.none?
-        return OS.linux? if os_name == :linux
-        return OS.mac? if os_name == :macos
-      end
-
-      return Homebrew::SimulateSystem.send("#{os_name}?")
-    end
+    return Homebrew::SimulateSystem.send("simulating_or_running_on_#{os_name}?") if BASE_OS_OPTIONS.include?(os_name)
 
     raise ArgumentError, "Invalid OS condition: #{os_name.inspect}" unless MacOSVersions::SYMBOLS.key?(os_name)
 
@@ -41,10 +33,10 @@ module OnSystem
       raise ArgumentError, "Invalid OS `or_*` condition: #{or_condition.inspect}"
     end
 
-    return false if Homebrew::SimulateSystem.linux? || (Homebrew::SimulateSystem.none? && OS.linux?)
+    return false if Homebrew::SimulateSystem.simulating_or_running_on_linux?
 
     base_os = MacOS::Version.from_symbol(os_name)
-    current_os = MacOS::Version.from_symbol(Homebrew::SimulateSystem.os || MacOS.version.to_sym)
+    current_os = MacOS::Version.from_symbol(Homebrew::SimulateSystem.current_os)
 
     return current_os >= base_os if or_condition == :or_newer
     return current_os <= base_os if or_condition == :or_older
diff --git a/Library/Homebrew/extend/os/linux/formula.rb b/Library/Homebrew/extend/os/linux/formula.rb
index da2d162bdf..f3586103bc 100644
--- a/Library/Homebrew/extend/os/linux/formula.rb
+++ b/Library/Homebrew/extend/os/linux/formula.rb
@@ -23,17 +23,4 @@ class Formula
 
   sig { params(targets: T.nilable(T.any(Pathname, String))).void }
   def deuniversalize_machos(*targets); end
-
-  class << self
-    undef ignore_missing_libraries
-
-    def ignore_missing_libraries(*libs)
-      libraries = libs.flatten
-      if libraries.any? { |x| !x.is_a?(String) && !x.is_a?(Regexp) }
-        raise FormulaSpecificationError, "#{__method__} can handle Strings and Regular Expressions only"
-      end
-
-      allowed_missing_libraries.merge(libraries)
-    end
-  end
 end
diff --git a/Library/Homebrew/extend/os/mac/software_spec.rb b/Library/Homebrew/extend/os/mac/software_spec.rb
deleted file mode 100644
index 1be80083e2..0000000000
--- a/Library/Homebrew/extend/os/mac/software_spec.rb
+++ /dev/null
@@ -1,27 +0,0 @@
-# typed: true
-# frozen_string_literal: true
-
-# The Library/Homebrew/extend/os/software_spec.rb conditional logic will need to be more nuanced
-# if this file ever includes more than `uses_from_macos`.
-class SoftwareSpec
-  undef uses_from_macos
-
-  def uses_from_macos(deps, bounds = {})
-    if deps.is_a?(Hash)
-      bounds = deps.dup
-      deps = [bounds.shift].to_h
-    end
-
-    @uses_from_macos_elements << deps
-
-    bounds = bounds.transform_values { |v| MacOS::Version.from_symbol(v) }
-
-    # Linux simulating macOS. Assume oldest macOS version.
-    return if Homebrew::EnvConfig.simulate_macos_on_linux? && !bounds.key?(:since)
-
-    # macOS new enough for dependency to not be required.
-    return if MacOS.version >= bounds[:since]
-
-    depends_on deps
-  end
-end
diff --git a/Library/Homebrew/extend/os/software_spec.rb b/Library/Homebrew/extend/os/software_spec.rb
index 32f46468f7..1e6f8f529c 100644
--- a/Library/Homebrew/extend/os/software_spec.rb
+++ b/Library/Homebrew/extend/os/software_spec.rb
@@ -1,9 +1,4 @@
 # typed: strict
 # frozen_string_literal: true
 
-# This logic will need to be more nuanced if this file includes more than `uses_from_macos`.
-if OS.mac? || Homebrew::EnvConfig.simulate_macos_on_linux?
-  require "extend/os/mac/software_spec"
-elsif OS.linux?
-  require "extend/os/linux/software_spec"
-end
+require "extend/os/linux/software_spec" if OS.linux?
diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index f52caa3650..d2f9ea56f2 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -3214,10 +3214,17 @@ class Formula
     end
 
     # Permit links to certain libraries that don't exist. Available on Linux only.
-    def ignore_missing_libraries(*)
-      return if Homebrew::SimulateSystem.linux?
+    def ignore_missing_libraries(*libs)
+      unless Homebrew::SimulateSystem.simulating_or_running_on_linux?
+        raise FormulaSpecificationError, "#{__method__} is available on Linux only"
+      end
 
-      raise FormulaSpecificationError, "#{__method__} is available on Linux only"
+      libraries = libs.flatten
+      if libraries.any? { |x| !x.is_a?(String) && !x.is_a?(Regexp) }
+        raise FormulaSpecificationError, "#{__method__} can handle Strings and Regular Expressions only"
+      end
+
+      allowed_missing_libraries.merge(libraries)
     end
 
     # @private
diff --git a/Library/Homebrew/formula_auditor.rb b/Library/Homebrew/formula_auditor.rb
index a06941104d..2cc9ad690e 100644
--- a/Library/Homebrew/formula_auditor.rb
+++ b/Library/Homebrew/formula_auditor.rb
@@ -307,6 +307,13 @@ module Homebrew
             EOS
           end
 
+          if dep_f.deprecated? && !formula.deprecated? && !formula.disabled?
+            problem <<~EOS
+              Dependency '#{dep.name}' is deprecated but has un-deprecated dependents. Either
+              un-deprecate '#{dep.name}' or deprecate it and all of its dependents.
+            EOS
+          end
+
           # we want to allow uses_from_macos for aliases but not bare dependencies
           if self.class.aliases.include?(dep.name) && spec.uses_from_macos_names.exclude?(dep.name)
             problem "Dependency '#{dep.name}' is an alias; use the canonical name '#{dep.to_formula.full_name}'."
@@ -410,13 +417,11 @@ module Homebrew
     end
 
     def audit_glibc
-      return if formula.name != "glibc"
       return unless @core_tap
+      return if formula.name != "glibc"
+      return if [OS::CI_GLIBC_VERSION, "2.27", "2.31", "2.35"].include?(formula.version.to_s)
 
-      version = formula.version.to_s
-      return if version == OS::CI_GLIBC_VERSION
-
-      problem "The glibc version must be #{version}, as this is the version used by our CI on Linux. " \
+      problem "The glibc version must be #{OS::CI_GLIBC_VERSION}, as this is the version used by our CI on Linux. " \
               "Glibc is for users who have a system Glibc with a lower version, " \
               "which allows them to use our Linux bottles, which were compiled against system Glibc on CI."
     end
diff --git a/Library/Homebrew/formulary.rb b/Library/Homebrew/formulary.rb
index df7bfff951..658b211c62 100644
--- a/Library/Homebrew/formulary.rb
+++ b/Library/Homebrew/formulary.rb
@@ -136,6 +136,18 @@ module Formulary
     class_s = Formulary.class_s(name)
     json_formula = Homebrew::API::Formula.all_formulae[name]
 
+    if (bottle_tag = Utils::Bottles.tag.to_s.presence) &&
+       (variations = json_formula["variations"].presence) &&
+       (variation = variations[bottle_tag].presence)
+      json_formula = json_formula.merge(variation)
+    end
+
+    uses_from_macos_names = json_formula["uses_from_macos"].map do |dep|
+      next dep unless dep.is_a? Hash
+
+      dep.keys.first
+    end
+
     klass = Class.new(::Formula) do
       desc json_formula["desc"]
       homepage json_formula["homepage"]
@@ -176,20 +188,18 @@ module Formulary
         disable! date: disable_date, because: reason
       end
 
-      json_formula["build_dependencies"].each do |dep|
-        depends_on dep => :build
-      end
-
       json_formula["dependencies"].each do |dep|
+        next if uses_from_macos_names.include? dep
+
         depends_on dep
       end
 
-      json_formula["recommended_dependencies"].each do |dep|
-        depends_on dep => :recommended
-      end
+      [:build, :recommended, :optional].each do |type|
+        json_formula["#{type}_dependencies"].each do |dep|
+          next if uses_from_macos_names.include? dep
 
-      json_formula["optional_dependencies"].each do |dep|
-        depends_on dep => :optional
+          depends_on dep => type
+        end
       end
 
       json_formula["uses_from_macos"].each do |dep|
diff --git a/Library/Homebrew/simulate_system.rb b/Library/Homebrew/simulate_system.rb
index d52a2af752..de61eabef7 100644
--- a/Library/Homebrew/simulate_system.rb
+++ b/Library/Homebrew/simulate_system.rb
@@ -32,19 +32,31 @@ module Homebrew
       end
 
       sig { returns(T::Boolean) }
-      def none?
-        @os.nil? && @arch.nil?
-      end
+      def simulating_or_running_on_macos?
+        return OS.mac? if @os.blank?
 
-      sig { returns(T::Boolean) }
-      def macos?
         [:macos, *MacOSVersions::SYMBOLS.keys].include?(@os)
       end
 
       sig { returns(T::Boolean) }
-      def linux?
+      def simulating_or_running_on_linux?
+        return OS.linux? if @os.blank?
+
         @os == :linux
       end
+
+      sig { returns(Symbol) }
+      def current_arch
+        @arch || Hardware::CPU.type
+      end
+
+      sig { returns(Symbol) }
+      def current_os
+        return @os if @os.present?
+        return :linux if OS.linux?
+
+        MacOS.version.to_sym
+      end
     end
   end
 end
diff --git a/Library/Homebrew/software_spec.rb b/Library/Homebrew/software_spec.rb
index c27f124aa6..30e9856d83 100644
--- a/Library/Homebrew/software_spec.rb
+++ b/Library/Homebrew/software_spec.rb
@@ -162,12 +162,25 @@ class SoftwareSpec
     add_dep_option(dep) if dep
   end
 
-  def uses_from_macos(spec, _bounds = {})
-    spec = [spec.dup.shift].to_h if spec.is_a?(Hash)
+  def uses_from_macos(deps, bounds = {})
+    if deps.is_a?(Hash)
+      bounds = deps.dup
+      deps = [bounds.shift].to_h
+    end
 
-    @uses_from_macos_elements << spec
+    @uses_from_macos_elements << deps
 
-    depends_on(spec)
+    # Linux simulating macOS. Assume oldest macOS version.
+    return if Homebrew::EnvConfig.simulate_macos_on_linux? && !bounds.key?(:since)
+
+    # macOS new enough for dependency to not be required.
+    if Homebrew::SimulateSystem.simulating_or_running_on_macos?
+      current_os = MacOS::Version.from_symbol(Homebrew::SimulateSystem.current_os)
+      since_os = MacOS::Version.from_symbol(bounds[:since]) if bounds.key?(:since)
+      return if current_os >= since_os
+    end
+
+    depends_on deps
   end
 
   def uses_from_macos_names
diff --git a/Library/Homebrew/test/formula_spec.rb b/Library/Homebrew/test/formula_spec.rb
index d4680abd7f..0883985623 100644
--- a/Library/Homebrew/test/formula_spec.rb
+++ b/Library/Homebrew/test/formula_spec.rb
@@ -1845,4 +1845,52 @@ describe Formula do
       expect(f.test).to eq(2)
     end
   end
+
+  describe "#ignore_missing_libraries" do
+    after do
+      Homebrew::SimulateSystem.clear
+    end
+
+    it "adds library to allowed_missing_libraries on Linux", :needs_linux do
+      Homebrew::SimulateSystem.clear
+      f = formula do
+        url "foo-1.0"
+
+        ignore_missing_libraries "bar.so"
+      end
+      expect(f.class.allowed_missing_libraries.to_a).to eq(["bar.so"])
+    end
+
+    it "adds library to allowed_missing_libraries on macOS when simulating Linux", :needs_macos do
+      Homebrew::SimulateSystem.os = :linux
+      f = formula do
+        url "foo-1.0"
+
+        ignore_missing_libraries "bar.so"
+      end
+      expect(f.class.allowed_missing_libraries.to_a).to eq(["bar.so"])
+    end
+
+    it "raises an error on macOS", :needs_macos do
+      Homebrew::SimulateSystem.clear
+      expect {
+        formula do
+          url "foo-1.0"
+
+          ignore_missing_libraries "bar.so"
+        end
+      }.to raise_error("ignore_missing_libraries is available on Linux only")
+    end
+
+    it "raises an error on Linux when simulating macOS", :needs_linux do
+      Homebrew::SimulateSystem.os = :macos
+      expect {
+        formula do
+          url "foo-1.0"
+
+          ignore_missing_libraries "bar.so"
+        end
+      }.to raise_error("ignore_missing_libraries is available on Linux only")
+    end
+  end
 end
diff --git a/Library/Homebrew/test/formulary_spec.rb b/Library/Homebrew/test/formulary_spec.rb
index 6276ecf876..0fc043fe6b 100644
--- a/Library/Homebrew/test/formulary_spec.rb
+++ b/Library/Homebrew/test/formulary_spec.rb
@@ -260,6 +260,26 @@ describe Formulary do
         }
       end
 
+      let(:variations_json) do
+        {
+          "variations" => {
+            Utils::Bottles.tag.to_s => {
+              "dependencies" => ["dep", "variations_dep"],
+            },
+          },
+        }
+      end
+
+      let(:linux_variations_json) do
+        {
+          "variations" => {
+            "x86_64_linux" => {
+              "dependencies" => ["dep", "uses_from_macos_dep"],
+            },
+          },
+        }
+      end
+
       before do
         allow(described_class).to receive(:loader_for).and_return(described_class::FormulaAPILoader.new(formula_name))
       end
@@ -303,6 +323,25 @@ describe Formulary do
           formula.install
         }.to raise_error("Cannot build from source from abstract formula.")
       end
+
+      it "returns a Formula with variations when given a name", :needs_macos do
+        allow(Homebrew::API::Formula).to receive(:all_formulae).and_return formula_json_contents(variations_json)
+
+        formula = described_class.factory(formula_name)
+        expect(formula).to be_kind_of(Formula)
+        expect(formula.deps.count).to eq 5
+        expect(formula.deps.map(&:name).include?("variations_dep")).to be true
+      end
+
+      it "returns a Formula without duplicated deps and uses_from_macos with variations on Linux", :needs_linux do
+        allow(Homebrew::API::Formula)
+          .to receive(:all_formulae).and_return formula_json_contents(linux_variations_json)
+
+        formula = described_class.factory(formula_name)
+        expect(formula).to be_kind_of(Formula)
+        expect(formula.deps.count).to eq 5
+        expect(formula.deps.map(&:name).include?("uses_from_macos_dep")).to be true
+      end
     end
   end
 
diff --git a/Library/Homebrew/test/os/mac/software_spec_spec.rb b/Library/Homebrew/test/os/mac/software_spec_spec.rb
deleted file mode 100644
index c6a72db735..0000000000
--- a/Library/Homebrew/test/os/mac/software_spec_spec.rb
+++ /dev/null
@@ -1,51 +0,0 @@
-# typed: false
-# frozen_string_literal: true
-
-require "software_spec"
-
-describe SoftwareSpec do
-  subject(:spec) { described_class.new }
-
-  describe "#uses_from_macos" do
-    before do
-      allow(OS).to receive(:mac?).and_return(true)
-      allow(OS::Mac).to receive(:version).and_return(OS::Mac::Version.from_symbol(:sierra))
-    end
-
-    it "adds a macOS dependency if the OS version meets requirements" do
-      spec.uses_from_macos("foo", since: :el_capitan)
-
-      expect(spec.deps).to be_empty
-      expect(spec.uses_from_macos_elements.first).to eq("foo")
-    end
-
-    it "doesn't add a macOS dependency if the OS version doesn't meet requirements" do
-      spec.uses_from_macos("foo", since: :high_sierra)
-
-      expect(spec.deps.first.name).to eq("foo")
-      expect(spec.uses_from_macos_elements).to eq(["foo"])
-    end
-
-    it "works with tags" do
-      spec.uses_from_macos("foo" => :build, :since => :high_sierra)
-
-      dep = spec.deps.first
-
-      expect(dep.name).to eq("foo")
-      expect(dep.tags).to include(:build)
-    end
-
-    it "doesn't add a dependency if no OS version is specified" do
-      spec.uses_from_macos("foo")
-      spec.uses_from_macos("bar" => :build)
-
-      expect(spec.deps).to be_empty
-    end
-
-    it "raises an error if passing invalid OS versions" do
-      expect {
-        spec.uses_from_macos("foo", since: :bar)
-      }.to raise_error(MacOSVersionError, "unknown or unsupported macOS version: :bar")
-    end
-  end
-end
diff --git a/Library/Homebrew/test/simulate_system_spec.rb b/Library/Homebrew/test/simulate_system_spec.rb
new file mode 100644
index 0000000000..0b72700d9f
--- /dev/null
+++ b/Library/Homebrew/test/simulate_system_spec.rb
@@ -0,0 +1,118 @@
+# typed: false
+# frozen_string_literal: true
+
+require "settings"
+
+describe Homebrew::SimulateSystem do
+  after do
+    described_class.clear
+  end
+
+  describe "::simulating_or_running_on_macos?" do
+    it "returns true on macOS", :needs_macos do
+      described_class.clear
+      expect(described_class.simulating_or_running_on_macos?).to be true
+    end
+
+    it "returns false on Linux", :needs_linux do
+      described_class.clear
+      expect(described_class.simulating_or_running_on_macos?).to be false
+    end
+
+    it "returns false on macOS when simulating Linux", :needs_macos do
+      described_class.clear
+      described_class.os = :linux
+      expect(described_class.simulating_or_running_on_macos?).to be false
+    end
+
+    it "returns true on Linux when simulating a generic macOS version", :needs_linux do
+      described_class.clear
+      described_class.os = :macos
+      expect(described_class.simulating_or_running_on_macos?).to be true
+    end
+
+    it "returns true on Linux when simulating a specific macOS version", :needs_linux do
+      described_class.clear
+      described_class.os = :monterey
+      expect(described_class.simulating_or_running_on_macos?).to be true
+    end
+  end
+
+  describe "::simulating_or_running_on_linux?" do
+    it "returns true on Linux", :needs_linux do
+      described_class.clear
+      expect(described_class.simulating_or_running_on_linux?).to be true
+    end
+
+    it "returns false on macOS", :needs_macos do
+      described_class.clear
+      expect(described_class.simulating_or_running_on_linux?).to be false
+    end
+
+    it "returns true on macOS when simulating Linux", :needs_macos do
+      described_class.clear
+      described_class.os = :linux
+      expect(described_class.simulating_or_running_on_linux?).to be true
+    end
+
+    it "returns false on Linux when simulating a generic macOS version", :needs_linux do
+      described_class.clear
+      described_class.os = :macos
+      expect(described_class.simulating_or_running_on_linux?).to be false
+    end
+
+    it "returns false on Linux when simulating a specific macOS version", :needs_linux do
+      described_class.clear
+      described_class.os = :monterey
+      expect(described_class.simulating_or_running_on_linux?).to be false
+    end
+  end
+
+  describe "::current_arch" do
+    it "returns the current architecture" do
+      described_class.clear
+      expect(described_class.current_arch).to eq Hardware::CPU.type
+    end
+
+    it "returns the simulated architecture" do
+      described_class.clear
+      simulated_arch = if Hardware::CPU.arm?
+        :intel
+      else
+        :arm
+      end
+      described_class.arch = simulated_arch
+      expect(described_class.current_arch).to eq simulated_arch
+    end
+  end
+
+  describe "::current_os" do
+    it "returns the current macOS version on macOS", :needs_macos do
+      described_class.clear
+      expect(described_class.current_os).to eq MacOS.version.to_sym
+    end
+
+    it "returns `:linux` on Linux", :needs_linux do
+      described_class.clear
+      expect(described_class.current_os).to eq :linux
+    end
+
+    it "returns `:linux` when simulating Linux on macOS", :needs_macos do
+      described_class.clear
+      described_class.os = :linux
+      expect(described_class.current_os).to eq :linux
+    end
+
+    it "returns `:macos` when simulating a generic macOS version on Linux", :needs_linux do
+      described_class.clear
+      described_class.os = :macos
+      expect(described_class.current_os).to eq :macos
+    end
+
+    it "returns `:macos` when simulating a specific macOS version on Linux", :needs_linux do
+      described_class.clear
+      described_class.os = :monterey
+      expect(described_class.current_os).to eq :monterey
+    end
+  end
+end
diff --git a/Library/Homebrew/test/software_spec_spec.rb b/Library/Homebrew/test/software_spec_spec.rb
index 284cf2211a..a737088803 100644
--- a/Library/Homebrew/test/software_spec_spec.rb
+++ b/Library/Homebrew/test/software_spec_spec.rb
@@ -135,27 +135,72 @@ describe SoftwareSpec do
     end
   end
 
-  describe "#uses_from_macos" do
-    it "allows specifying dependencies", :needs_linux do
-      spec.uses_from_macos("foo")
+  describe "#uses_from_macos", :needs_linux do
+    context "when running on Linux", :needs_linux do
+      it "allows specifying dependencies" do
+        spec.uses_from_macos("foo")
 
-      expect(spec.deps.first.name).to eq("foo")
+        expect(spec.deps.first.name).to eq("foo")
+      end
+
+      it "works with tags" do
+        spec.uses_from_macos("foo" => :build)
+
+        expect(spec.deps.first.name).to eq("foo")
+        expect(spec.deps.first.tags).to include(:build)
+      end
+
+      it "ignores OS version specifications" do
+        spec.uses_from_macos("foo", since: :mojave)
+        spec.uses_from_macos("bar" => :build, :since => :mojave)
+
+        expect(spec.deps.first.name).to eq("foo")
+        expect(spec.deps.last.name).to eq("bar")
+        expect(spec.deps.last.tags).to include(:build)
+      end
     end
 
-    it "works with tags", :needs_linux do
-      spec.uses_from_macos("foo" => :build)
+    context "when running on macOS", :needs_macos do
+      before do
+        allow(OS).to receive(:mac?).and_return(true)
+        allow(OS::Mac).to receive(:version).and_return(OS::Mac::Version.from_symbol(:sierra))
+      end
 
-      expect(spec.deps.first.name).to eq("foo")
-      expect(spec.deps.first.tags).to include(:build)
-    end
+      it "adds a macOS dependency if the OS version meets requirements" do
+        spec.uses_from_macos("foo", since: :el_capitan)
 
-    it "ignores OS version specifications", :needs_linux do
-      spec.uses_from_macos("foo", since: :mojave)
-      spec.uses_from_macos("bar" => :build, :since => :mojave)
+        expect(spec.deps).to be_empty
+        expect(spec.uses_from_macos_elements.first).to eq("foo")
+      end
 
-      expect(spec.deps.first.name).to eq("foo")
-      expect(spec.deps.last.name).to eq("bar")
-      expect(spec.deps.last.tags).to include(:build)
+      it "doesn't add a macOS dependency if the OS version doesn't meet requirements" do
+        spec.uses_from_macos("foo", since: :high_sierra)
+
+        expect(spec.deps.first.name).to eq("foo")
+        expect(spec.uses_from_macos_elements).to eq(["foo"])
+      end
+
+      it "works with tags" do
+        spec.uses_from_macos("foo" => :build, :since => :high_sierra)
+
+        dep = spec.deps.first
+
+        expect(dep.name).to eq("foo")
+        expect(dep.tags).to include(:build)
+      end
+
+      it "doesn't add a dependency if no OS version is specified" do
+        spec.uses_from_macos("foo")
+        spec.uses_from_macos("bar" => :build)
+
+        expect(spec.deps).to be_empty
+      end
+
+      it "raises an error if passing invalid OS versions" do
+        expect {
+          spec.uses_from_macos("foo", since: :bar)
+        }.to raise_error(MacOSVersionError, "unknown or unsupported macOS version: :bar")
+      end
     end
   end
 
diff --git a/Library/Homebrew/vendor/bundle/bundler/setup.rb b/Library/Homebrew/vendor/bundle/bundler/setup.rb
index 7fc5627185..b0b852f339 100644
--- a/Library/Homebrew/vendor/bundle/bundler/setup.rb
+++ b/Library/Homebrew/vendor/bundle/bundler/setup.rb
@@ -15,8 +15,8 @@ $:.unshift "#{path}/../#{ruby_engine}/#{ruby_version}/gems/ast-2.4.2/lib"
 $:.unshift "#{path}/../#{ruby_engine}/#{ruby_version}/gems/bindata-2.4.10/lib"
 $:.unshift "#{path}/../#{ruby_engine}/#{ruby_version}/extensions/x86_64-darwin-15/2.6.0-static/msgpack-1.5.4"
 $:.unshift "#{path}/../#{ruby_engine}/#{ruby_version}/gems/msgpack-1.5.4/lib"
-$:.unshift "#{path}/../#{ruby_engine}/#{ruby_version}/extensions/x86_64-darwin-15/2.6.0-static/bootsnap-1.12.0"
-$:.unshift "#{path}/../#{ruby_engine}/#{ruby_version}/gems/bootsnap-1.12.0/lib"
+$:.unshift "#{path}/../#{ruby_engine}/#{ruby_version}/extensions/x86_64-darwin-15/2.6.0-static/bootsnap-1.13.0"
+$:.unshift "#{path}/../#{ruby_engine}/#{ruby_version}/gems/bootsnap-1.13.0/lib"
 $:.unshift "#{path}/"
 $:.unshift "#{path}/../#{ruby_engine}/#{ruby_version}/extensions/x86_64-darwin-15/2.6.0-static/byebug-11.1.3"
 $:.unshift "#{path}/../#{ruby_engine}/#{ruby_version}/gems/byebug-11.1.3/lib"