diff --git a/lib/bundler.rb b/lib/bundler.rb
index 7df22ab3a5..24785ef5eb 100644
--- a/lib/bundler.rb
+++ b/lib/bundler.rb
@@ -53,13 +53,12 @@ module Bundler
   autoload :GemHelpers,             File.expand_path("bundler/gem_helpers", __dir__)
   autoload :GemVersionPromoter,     File.expand_path("bundler/gem_version_promoter", __dir__)
   autoload :Graph,                  File.expand_path("bundler/graph", __dir__)
-  autoload :IncompleteSpecification, File.expand_path("bundler/incomplete_specification", __dir__)
   autoload :Index,                  File.expand_path("bundler/index", __dir__)
   autoload :Injector,               File.expand_path("bundler/injector", __dir__)
   autoload :Installer,              File.expand_path("bundler/installer", __dir__)
   autoload :LazySpecification,      File.expand_path("bundler/lazy_specification", __dir__)
   autoload :LockfileParser,         File.expand_path("bundler/lockfile_parser", __dir__)
-  autoload :MatchPlatform,          File.expand_path("bundler/match_platform", __dir__)
+  autoload :MatchRemoteMetadata,    File.expand_path("bundler/match_remote_metadata", __dir__)
   autoload :ProcessLock,            File.expand_path("bundler/process_lock", __dir__)
   autoload :RemoteSpecification,    File.expand_path("bundler/remote_specification", __dir__)
   autoload :Resolver,               File.expand_path("bundler/resolver", __dir__)
@@ -332,9 +331,9 @@ module Bundler
       FileUtils.remove_entry_secure(path) if path && File.exist?(path)
     rescue ArgumentError
       message = <<EOF
-It is a security vulnerability to allow your home directory to be world-writable, and bundler can not continue.
+It is a security vulnerability to allow your home directory to be world-writable, and bundler cannot continue.
 You should probably consider fixing this issue by running `chmod o-w ~` on *nix.
-Please refer to https://ruby-doc.org/stdlib-2.1.2/libdoc/fileutils/rdoc/FileUtils.html#method-c-remove_entry_secure for details.
+Please refer to https://ruby-doc.org/stdlib-3.1.2/libdoc/fileutils/rdoc/FileUtils.html#method-c-remove_entry_secure for details.
 EOF
       File.world_writable?(path) ? Bundler.ui.warn(message) : raise
       raise PathError, "Please fix the world-writable issue with your #{path} directory"
diff --git a/lib/bundler/cli/platform.rb b/lib/bundler/cli/platform.rb
index 16d4e0145a..73da8cf80e 100644
--- a/lib/bundler/cli/platform.rb
+++ b/lib/bundler/cli/platform.rb
@@ -9,7 +9,7 @@ module Bundler
 
     def run
       platforms, ruby_version = Bundler.ui.silence do
-        locked_ruby_version = Bundler.locked_gems && Bundler.locked_gems.ruby_version.gsub(/p\d+\Z/, "")
+        locked_ruby_version = Bundler.locked_gems && Bundler.locked_gems.ruby_version&.gsub(/p\d+\Z/, "")
         gemfile_ruby_version = Bundler.definition.ruby_version && Bundler.definition.ruby_version.single_version_string
         [Bundler.definition.platforms.map {|p| "* #{p}" },
          locked_ruby_version || gemfile_ruby_version]
diff --git a/lib/bundler/definition.rb b/lib/bundler/definition.rb
index 21c06e55ba..66efd82b53 100644
--- a/lib/bundler/definition.rb
+++ b/lib/bundler/definition.rb
@@ -145,8 +145,6 @@ module Bundler
       @dependency_changes = converge_dependencies
       @local_changes = converge_locals
 
-      @reresolve = nil
-
       @requires = compute_requires
     end
 
@@ -218,6 +216,7 @@ module Bundler
       true
     rescue BundlerError => e
       @resolve = nil
+      @resolver = nil
       @specs = nil
       @gem_version_promoter = nil
 
@@ -288,7 +287,7 @@ module Bundler
         end
       else
         Bundler.ui.debug("Found changes from the lockfile, re-resolving dependencies because #{change_reason}")
-        @reresolve = reresolve
+        resolver.start(expanded_dependencies)
       end
     end
 
@@ -482,11 +481,18 @@ module Bundler
 
     private
 
-    def reresolve
-      last_resolve = converge_locked_specs
-      remove_ruby_from_platforms_if_necessary!(dependencies)
-      expanded_dependencies = expand_dependencies(dependencies + metadata_dependencies, true)
-      Resolver.resolve(expanded_dependencies, source_requirements, last_resolve, gem_version_promoter, additional_base_requirements_for_resolve, platforms)
+    def resolver
+      @resolver ||= begin
+        last_resolve = converge_locked_specs
+        Resolver.new(source_requirements, last_resolve, gem_version_promoter, additional_base_requirements_for_resolve, platforms)
+      end
+    end
+
+    def expanded_dependencies
+      @expanded_dependencies ||= begin
+        remove_ruby_from_platforms_if_necessary!(dependencies)
+        expand_dependencies(dependencies + metadata_dependencies, true)
+      end
     end
 
     def filter_specs(specs, deps)
@@ -514,15 +520,13 @@ module Bundler
         raise GemNotFound, "Could not find #{missing_specs_list.join(" nor ")}"
       end
 
-      if @reresolve.nil?
+      loop do
         incomplete_specs = specs.incomplete_specs
+        break if incomplete_specs.empty?
 
-        if incomplete_specs.any?
-          Bundler.ui.debug("The lockfile does not have all gems needed for the current platform though, Bundler will still re-resolve dependencies")
-          @unlock[:gems].concat(incomplete_specs.map(&:name))
-          @resolve = reresolve
-          specs = resolve.materialize(dependencies)
-        end
+        Bundler.ui.debug("The lockfile does not have all gems needed for the current platform though, Bundler will still re-resolve dependencies")
+        @resolve = resolver.start(expanded_dependencies, :exclude_specs => incomplete_specs)
+        specs = resolve.materialize(dependencies)
       end
 
       bundler = sources.metadata_source.specs.search(Gem::Dependency.new("bundler", VERSION)).last
@@ -715,7 +719,9 @@ module Bundler
     # commonly happen if the Gemfile has changed since the lockfile was last
     # generated
     def converge_locked_specs
-      resolve = converge_specs(@locked_specs)
+      converged = converge_specs(@locked_specs)
+
+      resolve = SpecSet.new(converged.reject {|s| @unlock[:gems].include?(s.name) })
 
       diff = nil
 
@@ -788,7 +794,7 @@ module Bundler
         end
       end
 
-      SpecSet.new(filter_specs(converged, deps).reject {|s| @unlock[:gems].include?(s.name) })
+      filter_specs(converged, deps)
     end
 
     def metadata_dependencies
@@ -877,10 +883,8 @@ module Bundler
     def additional_base_requirements_for_resolve
       return [] unless @locked_gems && unlocking? && !sources.expired_sources?(@locked_gems.sources)
       converge_specs(@originally_locked_specs).map do |locked_spec|
-        name = locked_spec.name
-        dep = Dependency.new(name, ">= #{locked_spec.version}")
-        DepProxy.get_proxy(dep, locked_spec.platform)
-      end
+        Dependency.new(locked_spec.name, ">= #{locked_spec.version}")
+      end.uniq
     end
 
     def remove_ruby_from_platforms_if_necessary!(dependencies)
@@ -888,10 +892,11 @@ module Bundler
                 Bundler.local_platform == Gem::Platform::RUBY ||
                 !platforms.include?(Gem::Platform::RUBY) ||
                 (@new_platform && platforms.last == Gem::Platform::RUBY) ||
-                !@originally_locked_specs.incomplete_ruby_specs?(dependencies)
+                !@originally_locked_specs.incomplete_ruby_specs?(expand_dependencies(dependencies))
 
       remove_platform(Gem::Platform::RUBY)
       add_current_platform
+      resolver.platforms = @platforms
     end
 
     def source_map
diff --git a/lib/bundler/endpoint_specification.rb b/lib/bundler/endpoint_specification.rb
index e9aa366b41..ea197328ba 100644
--- a/lib/bundler/endpoint_specification.rb
+++ b/lib/bundler/endpoint_specification.rb
@@ -3,7 +3,7 @@
 module Bundler
   # used for Creating Specifications from the Gemcutter Endpoint
   class EndpointSpecification < Gem::Specification
-    include MatchPlatform
+    include MatchRemoteMetadata
 
     attr_reader :name, :version, :platform, :checksum
     attr_accessor :source, :remote, :dependencies
@@ -22,17 +22,6 @@ module Bundler
       parse_metadata(metadata)
     end
 
-    def required_ruby_version
-      @required_ruby_version ||= _remote_specification.required_ruby_version
-    end
-
-    # A fallback is included because the original version of the specification
-    # API didn't include that field, so some marshalled specs in the index have it
-    # set to +nil+.
-    def required_rubygems_version
-      @required_rubygems_version ||= _remote_specification.required_rubygems_version || Gem::Requirement.default
-    end
-
     def fetch_platform
       @platform
     end
diff --git a/lib/bundler/gem_version_promoter.rb b/lib/bundler/gem_version_promoter.rb
index 3cce3f2139..ddf7446dd2 100644
--- a/lib/bundler/gem_version_promoter.rb
+++ b/lib/bundler/gem_version_promoter.rb
@@ -88,6 +88,10 @@ module Bundler
       end
     end
 
+    def reset
+      @sort_versions = {}
+    end
+
     # @return [bool] Convenience method for testing value of level variable.
     def major?
       level == :major
diff --git a/lib/bundler/incomplete_specification.rb b/lib/bundler/incomplete_specification.rb
deleted file mode 100644
index 6d0b9b901c..0000000000
--- a/lib/bundler/incomplete_specification.rb
+++ /dev/null
@@ -1,12 +0,0 @@
-# frozen_string_literal: true
-
-module Bundler
-  class IncompleteSpecification
-    attr_reader :name, :platform
-
-    def initialize(name, platform)
-      @name = name
-      @platform = platform
-    end
-  end
-end
diff --git a/lib/bundler/inline.rb b/lib/bundler/inline.rb
index 8ef580f1f0..25e055fbe4 100644
--- a/lib/bundler/inline.rb
+++ b/lib/bundler/inline.rb
@@ -54,7 +54,7 @@ def gemfile(install = false, options = {}, &gemfile)
 
       Bundler.ui = install ? ui : Bundler::UI::Silent.new
       if install || definition.missing_specs?
-        Bundler.settings.temporary(:inline => true) do
+        Bundler.settings.temporary(:inline => true, :no_install => false) do
           installer = Bundler::Installer.install(Bundler.root, definition, :system => true)
           installer.post_install_messages.each do |name, message|
             Bundler.ui.info "Post-install message from #{name}:\n#{message}"
diff --git a/lib/bundler/installer.rb b/lib/bundler/installer.rb
index b7b0e36dfd..1b17de5d4e 100644
--- a/lib/bundler/installer.rb
+++ b/lib/bundler/installer.rb
@@ -238,19 +238,14 @@ module Bundler
     end
 
     def ensure_specs_are_compatible!
-      system_ruby = Bundler::RubyVersion.system
-      rubygems_version = Bundler.rubygems.version
       @definition.specs.each do |spec|
-        if required_ruby_version = spec.required_ruby_version
-          unless required_ruby_version.satisfied_by?(system_ruby.gem_version)
-            raise InstallError, "#{spec.full_name} requires ruby version #{required_ruby_version}, " \
-              "which is incompatible with the current version, #{system_ruby}"
-          end
+        unless spec.matches_current_ruby?
+          raise InstallError, "#{spec.full_name} requires ruby version #{spec.required_ruby_version}, " \
+            "which is incompatible with the current version, #{Gem.ruby_version}"
         end
-        next unless required_rubygems_version = spec.required_rubygems_version
-        unless required_rubygems_version.satisfied_by?(rubygems_version)
-          raise InstallError, "#{spec.full_name} requires rubygems version #{required_rubygems_version}, " \
-            "which is incompatible with the current version, #{rubygems_version}"
+        unless spec.matches_current_rubygems?
+          raise InstallError, "#{spec.full_name} requires rubygems version #{spec.required_rubygems_version}, " \
+            "which is incompatible with the current version, #{Gem.rubygems_version}"
         end
       end
     end
diff --git a/lib/bundler/lazy_specification.rb b/lib/bundler/lazy_specification.rb
index 5b40bec5a8..ec141cfa27 100644
--- a/lib/bundler/lazy_specification.rb
+++ b/lib/bundler/lazy_specification.rb
@@ -1,7 +1,5 @@
 # frozen_string_literal: true
 
-require_relative "match_platform"
-
 module Bundler
   class LazySpecification
     include MatchPlatform
@@ -97,8 +95,8 @@ module Bundler
       @specification = begin
         search = candidates.reverse.find do |spec|
           spec.is_a?(StubSpecification) ||
-            (spec.required_ruby_version.satisfied_by?(Gem.ruby_version) &&
-              spec.required_rubygems_version.satisfied_by?(Gem.rubygems_version))
+            (spec.matches_current_ruby? &&
+              spec.matches_current_rubygems?)
         end
         if search.nil? && Bundler.frozen_bundle?
           search = candidates.last
diff --git a/lib/bundler/man/bundle-add.1 b/lib/bundler/man/bundle-add.1
index 20430a78a0..f6e5004b5b 100644
--- a/lib/bundler/man/bundle-add.1
+++ b/lib/bundler/man/bundle-add.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-ADD" "1" "July 2022" "" ""
+.TH "BUNDLE\-ADD" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-add\fR \- Add gem to the Gemfile and run bundle install
diff --git a/lib/bundler/man/bundle-binstubs.1 b/lib/bundler/man/bundle-binstubs.1
index 9c57c7c9c5..d1204104b1 100644
--- a/lib/bundler/man/bundle-binstubs.1
+++ b/lib/bundler/man/bundle-binstubs.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-BINSTUBS" "1" "July 2022" "" ""
+.TH "BUNDLE\-BINSTUBS" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-binstubs\fR \- Install the binstubs of the listed gems
diff --git a/lib/bundler/man/bundle-cache.1 b/lib/bundler/man/bundle-cache.1
index fdaaa3b92a..1393caec65 100644
--- a/lib/bundler/man/bundle-cache.1
+++ b/lib/bundler/man/bundle-cache.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CACHE" "1" "July 2022" "" ""
+.TH "BUNDLE\-CACHE" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-cache\fR \- Package your needed \fB\.gem\fR files into your application
diff --git a/lib/bundler/man/bundle-check.1 b/lib/bundler/man/bundle-check.1
index 5be7886274..71ddb5cee3 100644
--- a/lib/bundler/man/bundle-check.1
+++ b/lib/bundler/man/bundle-check.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CHECK" "1" "July 2022" "" ""
+.TH "BUNDLE\-CHECK" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-check\fR \- Verifies if dependencies are satisfied by installed gems
diff --git a/lib/bundler/man/bundle-clean.1 b/lib/bundler/man/bundle-clean.1
index 2bb95ed2de..e5dc4ccf92 100644
--- a/lib/bundler/man/bundle-clean.1
+++ b/lib/bundler/man/bundle-clean.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CLEAN" "1" "July 2022" "" ""
+.TH "BUNDLE\-CLEAN" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-clean\fR \- Cleans up unused gems in your bundler directory
diff --git a/lib/bundler/man/bundle-config.1 b/lib/bundler/man/bundle-config.1
index 9f7887ca91..ffc91ed492 100644
--- a/lib/bundler/man/bundle-config.1
+++ b/lib/bundler/man/bundle-config.1
@@ -1,13 +1,22 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-CONFIG" "1" "July 2022" "" ""
+.TH "BUNDLE\-CONFIG" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-config\fR \- Set bundler configuration options
 .
 .SH "SYNOPSIS"
-\fBbundle config\fR [list|get|set|unset] [\fIname\fR [\fIvalue\fR]]
+\fBbundle config\fR list
+.
+.br
+\fBbundle config\fR [get] NAME
+.
+.br
+\fBbundle config\fR [set] NAME VALUE
+.
+.br
+\fBbundle config\fR unset NAME
 .
 .SH "DESCRIPTION"
 This command allows you to interact with Bundler\'s configuration system\.
diff --git a/lib/bundler/man/bundle-config.1.ronn b/lib/bundler/man/bundle-config.1.ronn
index 905c85fcd9..6f9edc9c39 100644
--- a/lib/bundler/man/bundle-config.1.ronn
+++ b/lib/bundler/man/bundle-config.1.ronn
@@ -3,7 +3,10 @@ bundle-config(1) -- Set bundler configuration options
 
 ## SYNOPSIS
 
-`bundle config` [list|get|set|unset] [<name> [<value>]]
+`bundle config` list<br>
+`bundle config` [get] NAME<br>
+`bundle config` [set] NAME VALUE<br>
+`bundle config` unset NAME
 
 ## DESCRIPTION
 
diff --git a/lib/bundler/man/bundle-doctor.1 b/lib/bundler/man/bundle-doctor.1
index 6aad9858db..3f18aaf569 100644
--- a/lib/bundler/man/bundle-doctor.1
+++ b/lib/bundler/man/bundle-doctor.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-DOCTOR" "1" "July 2022" "" ""
+.TH "BUNDLE\-DOCTOR" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-doctor\fR \- Checks the bundle for common problems
diff --git a/lib/bundler/man/bundle-exec.1 b/lib/bundler/man/bundle-exec.1
index 210dd178e8..7f6a892f6c 100644
--- a/lib/bundler/man/bundle-exec.1
+++ b/lib/bundler/man/bundle-exec.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-EXEC" "1" "July 2022" "" ""
+.TH "BUNDLE\-EXEC" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-exec\fR \- Execute a command in the context of the bundle
diff --git a/lib/bundler/man/bundle-gem.1 b/lib/bundler/man/bundle-gem.1
index 0fb6f7d0ab..63d611bdd2 100644
--- a/lib/bundler/man/bundle-gem.1
+++ b/lib/bundler/man/bundle-gem.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-GEM" "1" "July 2022" "" ""
+.TH "BUNDLE\-GEM" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-gem\fR \- Generate a project skeleton for creating a rubygem
diff --git a/lib/bundler/man/bundle-info.1 b/lib/bundler/man/bundle-info.1
index d3bad843b8..ae9bc48539 100644
--- a/lib/bundler/man/bundle-info.1
+++ b/lib/bundler/man/bundle-info.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INFO" "1" "July 2022" "" ""
+.TH "BUNDLE\-INFO" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-info\fR \- Show information for the given gem in your bundle
diff --git a/lib/bundler/man/bundle-init.1 b/lib/bundler/man/bundle-init.1
index 0b3abfeefc..0b06ce8997 100644
--- a/lib/bundler/man/bundle-init.1
+++ b/lib/bundler/man/bundle-init.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INIT" "1" "July 2022" "" ""
+.TH "BUNDLE\-INIT" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-init\fR \- Generates a Gemfile into the current working directory
diff --git a/lib/bundler/man/bundle-inject.1 b/lib/bundler/man/bundle-inject.1
index 53f2eaae0a..4ad37ec3eb 100644
--- a/lib/bundler/man/bundle-inject.1
+++ b/lib/bundler/man/bundle-inject.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INJECT" "1" "July 2022" "" ""
+.TH "BUNDLE\-INJECT" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-inject\fR \- Add named gem(s) with version requirements to Gemfile
diff --git a/lib/bundler/man/bundle-install.1 b/lib/bundler/man/bundle-install.1
index 8e94fe2437..f219a062b1 100644
--- a/lib/bundler/man/bundle-install.1
+++ b/lib/bundler/man/bundle-install.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-INSTALL" "1" "July 2022" "" ""
+.TH "BUNDLE\-INSTALL" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-install\fR \- Install the dependencies specified in your Gemfile
diff --git a/lib/bundler/man/bundle-list.1 b/lib/bundler/man/bundle-list.1
index 3a9cc9a237..6e89f810a1 100644
--- a/lib/bundler/man/bundle-list.1
+++ b/lib/bundler/man/bundle-list.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-LIST" "1" "July 2022" "" ""
+.TH "BUNDLE\-LIST" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-list\fR \- List all the gems in the bundle
diff --git a/lib/bundler/man/bundle-lock.1 b/lib/bundler/man/bundle-lock.1
index ac03c5478e..f5f0ce2bdb 100644
--- a/lib/bundler/man/bundle-lock.1
+++ b/lib/bundler/man/bundle-lock.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-LOCK" "1" "July 2022" "" ""
+.TH "BUNDLE\-LOCK" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-lock\fR \- Creates / Updates a lockfile without installing
diff --git a/lib/bundler/man/bundle-open.1 b/lib/bundler/man/bundle-open.1
index be6c5af248..7bda0afd33 100644
--- a/lib/bundler/man/bundle-open.1
+++ b/lib/bundler/man/bundle-open.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-OPEN" "1" "July 2022" "" ""
+.TH "BUNDLE\-OPEN" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-open\fR \- Opens the source directory for a gem in your bundle
diff --git a/lib/bundler/man/bundle-outdated.1 b/lib/bundler/man/bundle-outdated.1
index fc3d5e8caf..a2b8e2bf92 100644
--- a/lib/bundler/man/bundle-outdated.1
+++ b/lib/bundler/man/bundle-outdated.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-OUTDATED" "1" "July 2022" "" ""
+.TH "BUNDLE\-OUTDATED" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-outdated\fR \- List installed gems with newer versions available
diff --git a/lib/bundler/man/bundle-platform.1 b/lib/bundler/man/bundle-platform.1
index f5a90c59e9..7fda4ef046 100644
--- a/lib/bundler/man/bundle-platform.1
+++ b/lib/bundler/man/bundle-platform.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-PLATFORM" "1" "July 2022" "" ""
+.TH "BUNDLE\-PLATFORM" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-platform\fR \- Displays platform compatibility information
diff --git a/lib/bundler/man/bundle-plugin.1 b/lib/bundler/man/bundle-plugin.1
new file mode 100644
index 0000000000..7210806327
--- /dev/null
+++ b/lib/bundler/man/bundle-plugin.1
@@ -0,0 +1,81 @@
+.\" generated with Ronn/v0.7.3
+.\" http://github.com/rtomayko/ronn/tree/0.7.3
+.
+.TH "BUNDLE\-PLUGIN" "1" "August 2022" "" ""
+.
+.SH "NAME"
+\fBbundle\-plugin\fR \- Manage Bundler plugins
+.
+.SH "SYNOPSIS"
+\fBbundle plugin\fR install PLUGINS [\-\-source=\fISOURCE\fR] [\-\-version=\fIversion\fR] [\-\-git|\-\-local_git=\fIgit\-url\fR] [\-\-branch=\fIbranch\fR|\-\-ref=\fIrev\fR]
+.
+.br
+\fBbundle plugin\fR uninstall PLUGINS
+.
+.br
+\fBbundle plugin\fR list
+.
+.br
+\fBbundle plugin\fR help [COMMAND]
+.
+.SH "DESCRIPTION"
+You can install, uninstall, and list plugin(s) with this command to extend functionalities of Bundler\.
+.
+.SH "SUB\-COMMANDS"
+.
+.SS "install"
+Install the given plugin(s)\.
+.
+.IP "\(bu" 4
+\fBbundle plugin install bundler\-graph\fR: Install bundler\-graph gem from RubyGems\.org\. The global source, specified in source in Gemfile is ignored\.
+.
+.IP "\(bu" 4
+\fBbundle plugin install bundler\-graph \-\-source https://example\.com\fR: Install bundler\-graph gem from example\.com\. The global source, specified in source in Gemfile is not considered\.
+.
+.IP "\(bu" 4
+\fBbundle plugin install bundler\-graph \-\-version 0\.2\.1\fR: You can specify the version of the gem via \fB\-\-version\fR\.
+.
+.IP "\(bu" 4
+\fBbundle plugin install bundler\-graph \-\-git https://github\.com/rubygems/bundler\-graph\fR: Install bundler\-graph gem from Git repository\. \fB\-\-git\fR can be replaced with \fB\-\-local\-git\fR\. You cannot use both \fB\-\-git\fR and \fB\-\-local\-git\fR\. You can use standard Git URLs like:
+.
+.IP "\(bu" 4
+\fBssh://[user@]host\.xz[:port]/path/to/repo\.git\fR
+.
+.IP "\(bu" 4
+\fBhttp[s]://host\.xz[:port]/path/to/repo\.git\fR
+.
+.IP "\(bu" 4
+\fB/path/to/repo\fR
+.
+.IP "\(bu" 4
+\fBfile:///path/to/repo\fR
+.
+.IP "" 0
+.
+.IP
+When you specify \fB\-\-git\fR/\fB\-\-local\-git\fR, you can use \fB\-\-branch\fR or \fB\-\-ref\fR to specify any branch, tag, or commit hash (revision) to use\. When you specify both, only the latter is used\.
+.
+.IP "" 0
+.
+.SS "uninstall"
+Uninstall the plugin(s) specified in PLUGINS\.
+.
+.SS "list"
+List the installed plugins and available commands\.
+.
+.P
+No options\.
+.
+.SS "help"
+Describe subcommands or one specific subcommand\.
+.
+.P
+No options\.
+.
+.SH "SEE ALSO"
+.
+.IP "\(bu" 4
+How to write a Bundler plugin \fIhttps://bundler\.io/guides/bundler_plugins\.html\fR
+.
+.IP "" 0
+
diff --git a/lib/bundler/man/bundle-plugin.1.ronn b/lib/bundler/man/bundle-plugin.1.ronn
new file mode 100644
index 0000000000..4f234eeba7
--- /dev/null
+++ b/lib/bundler/man/bundle-plugin.1.ronn
@@ -0,0 +1,59 @@
+bundle-plugin(1) -- Manage Bundler plugins
+==========================================
+
+## SYNOPSIS
+
+`bundle plugin` install PLUGINS [--source=<SOURCE>] [--version=<version>]
+                              [--git|--local_git=<git-url>] [--branch=<branch>|--ref=<rev>]<br>
+`bundle plugin` uninstall PLUGINS<br>
+`bundle plugin` list<br>
+`bundle plugin` help [COMMAND]
+
+## DESCRIPTION
+
+You can install, uninstall, and list plugin(s) with this command to extend functionalities of Bundler.
+
+## SUB-COMMANDS
+
+### install
+
+Install the given plugin(s).
+
+* `bundle plugin install bundler-graph`:
+  Install bundler-graph gem from RubyGems.org. The global source, specified in source in Gemfile is ignored.
+
+* `bundle plugin install bundler-graph --source https://example.com`:
+  Install bundler-graph gem from example.com. The global source, specified in source in Gemfile is not considered.
+
+* `bundle plugin install bundler-graph --version 0.2.1`:
+  You can specify the version of the gem via `--version`.
+
+* `bundle plugin install bundler-graph --git https://github.com/rubygems/bundler-graph`:
+  Install bundler-graph gem from Git repository. `--git` can be replaced with `--local-git`. You cannot use both `--git` and `--local-git`. You can use standard Git URLs like:
+
+  * `ssh://[user@]host.xz[:port]/path/to/repo.git`
+  * `http[s]://host.xz[:port]/path/to/repo.git`
+  * `/path/to/repo`
+  * `file:///path/to/repo`
+
+  When you specify `--git`/`--local-git`, you can use `--branch` or `--ref` to specify any branch, tag, or commit hash (revision) to use. When you specify both, only the latter is used.
+
+### uninstall
+
+Uninstall the plugin(s) specified in PLUGINS.
+
+### list
+
+List the installed plugins and available commands.
+
+No options.
+
+### help
+
+Describe subcommands or one specific subcommand.
+
+No options.
+
+## SEE ALSO
+
+* [How to write a Bundler plugin](https://bundler.io/guides/bundler_plugins.html)
diff --git a/lib/bundler/man/bundle-pristine.1 b/lib/bundler/man/bundle-pristine.1
index 44e5a83a01..d635d24e2d 100644
--- a/lib/bundler/man/bundle-pristine.1
+++ b/lib/bundler/man/bundle-pristine.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-PRISTINE" "1" "July 2022" "" ""
+.TH "BUNDLE\-PRISTINE" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-pristine\fR \- Restores installed gems to their pristine condition
diff --git a/lib/bundler/man/bundle-remove.1 b/lib/bundler/man/bundle-remove.1
index 29ec246018..4952e8094e 100644
--- a/lib/bundler/man/bundle-remove.1
+++ b/lib/bundler/man/bundle-remove.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-REMOVE" "1" "July 2022" "" ""
+.TH "BUNDLE\-REMOVE" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-remove\fR \- Removes gems from the Gemfile
diff --git a/lib/bundler/man/bundle-show.1 b/lib/bundler/man/bundle-show.1
index 227b1c8a1e..72ef3283cc 100644
--- a/lib/bundler/man/bundle-show.1
+++ b/lib/bundler/man/bundle-show.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-SHOW" "1" "July 2022" "" ""
+.TH "BUNDLE\-SHOW" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-show\fR \- Shows all the gems in your bundle, or the path to a gem
diff --git a/lib/bundler/man/bundle-update.1 b/lib/bundler/man/bundle-update.1
index 7d0988bfa5..06ceef85db 100644
--- a/lib/bundler/man/bundle-update.1
+++ b/lib/bundler/man/bundle-update.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-UPDATE" "1" "July 2022" "" ""
+.TH "BUNDLE\-UPDATE" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-update\fR \- Update your gems to the latest available versions
diff --git a/lib/bundler/man/bundle-viz.1 b/lib/bundler/man/bundle-viz.1
index f6f51cde0e..cf63dd8f9e 100644
--- a/lib/bundler/man/bundle-viz.1
+++ b/lib/bundler/man/bundle-viz.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE\-VIZ" "1" "July 2022" "" ""
+.TH "BUNDLE\-VIZ" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\-viz\fR \- Generates a visual dependency graph for your Gemfile
diff --git a/lib/bundler/man/bundle.1 b/lib/bundler/man/bundle.1
index f683e78cc6..22e102e053 100644
--- a/lib/bundler/man/bundle.1
+++ b/lib/bundler/man/bundle.1
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "BUNDLE" "1" "July 2022" "" ""
+.TH "BUNDLE" "1" "August 2022" "" ""
 .
 .SH "NAME"
 \fBbundle\fR \- Ruby Dependency Management
@@ -120,6 +120,10 @@ Display warnings about common problems
 \fBbundle remove(1)\fR \fIbundle\-remove\.1\.html\fR
 Removes gems from the Gemfile
 .
+.TP
+\fBbundle plugin(1)\fR \fIbundle\-plugin\.1\.html\fR
+Manage Bundler plugins
+.
 .SH "PLUGINS"
 When running a command that isn\'t listed in PRIMARY COMMANDS or UTILITIES, Bundler will try to find an executable on your path named \fBbundler\-<command>\fR and execute it, passing down any extra arguments to it\.
 .
diff --git a/lib/bundler/man/bundle.1.ronn b/lib/bundler/man/bundle.1.ronn
index 8f0159eee5..94106b183c 100644
--- a/lib/bundler/man/bundle.1.ronn
+++ b/lib/bundler/man/bundle.1.ronn
@@ -97,6 +97,9 @@ We divide `bundle` subcommands into primary commands and utilities:
 * [`bundle remove(1)`](bundle-remove.1.html):
   Removes gems from the Gemfile
 
+* [`bundle plugin(1)`](bundle-plugin.1.html):
+  Manage Bundler plugins
+
 ## PLUGINS
 
 When running a command that isn't listed in PRIMARY COMMANDS or UTILITIES,
diff --git a/lib/bundler/man/gemfile.5 b/lib/bundler/man/gemfile.5
index 63a16ca3ff..3d3994153b 100644
--- a/lib/bundler/man/gemfile.5
+++ b/lib/bundler/man/gemfile.5
@@ -1,7 +1,7 @@
 .\" generated with Ronn/v0.7.3
 .\" http://github.com/rtomayko/ronn/tree/0.7.3
 .
-.TH "GEMFILE" "5" "July 2022" "" ""
+.TH "GEMFILE" "5" "August 2022" "" ""
 .
 .SH "NAME"
 \fBGemfile\fR \- A format for describing gem dependencies for Ruby programs
diff --git a/lib/bundler/man/index.txt b/lib/bundler/man/index.txt
index ef2956b2f9..b895aa537d 100644
--- a/lib/bundler/man/index.txt
+++ b/lib/bundler/man/index.txt
@@ -18,6 +18,7 @@ bundle-lock(1)        bundle-lock.1
 bundle-open(1)        bundle-open.1
 bundle-outdated(1)    bundle-outdated.1
 bundle-platform(1)    bundle-platform.1
+bundle-plugin(1)      bundle-plugin.1
 bundle-pristine(1)    bundle-pristine.1
 bundle-remove(1)      bundle-remove.1
 bundle-show(1)        bundle-show.1
diff --git a/lib/bundler/match_metadata.rb b/lib/bundler/match_metadata.rb
new file mode 100644
index 0000000000..499036ca93
--- /dev/null
+++ b/lib/bundler/match_metadata.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module Bundler
+  module MatchMetadata
+    def matches_current_ruby?
+      @required_ruby_version.satisfied_by?(Gem.ruby_version)
+    end
+
+    def matches_current_rubygems?
+      @required_rubygems_version.satisfied_by?(Gem.rubygems_version)
+    end
+  end
+end
diff --git a/lib/bundler/match_remote_metadata.rb b/lib/bundler/match_remote_metadata.rb
new file mode 100644
index 0000000000..e1b2f4d0e2
--- /dev/null
+++ b/lib/bundler/match_remote_metadata.rb
@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+module Bundler
+  module FetchMetadata
+    def matches_current_ruby?
+      @required_ruby_version ||= _remote_specification.required_ruby_version
+
+      super
+    end
+
+    def matches_current_rubygems?
+      # A fallback is included because the original version of the specification
+      # API didn't include that field, so some marshalled specs in the index have it
+      # set to +nil+.
+      @required_rubygems_version ||= _remote_specification.required_rubygems_version || Gem::Requirement.default
+
+      super
+    end
+  end
+
+  module MatchRemoteMetadata
+    include MatchMetadata
+
+    prepend FetchMetadata
+  end
+end
diff --git a/lib/bundler/plugin.rb b/lib/bundler/plugin.rb
index 158c69e1a1..26458bd596 100644
--- a/lib/bundler/plugin.rb
+++ b/lib/bundler/plugin.rb
@@ -36,6 +36,8 @@ module Bundler
     # @param [Hash] options various parameters as described in description.
     #               Refer to cli/plugin for available options
     def install(names, options)
+      raise InvalidOption, "You cannot specify `--branch` and `--ref` at the same time." if options["branch"] && options["ref"]
+
       specs = Installer.new.install(names, options)
 
       save_plugins names, specs
diff --git a/lib/bundler/remote_specification.rb b/lib/bundler/remote_specification.rb
index b5d7e3a6c9..601957746f 100644
--- a/lib/bundler/remote_specification.rb
+++ b/lib/bundler/remote_specification.rb
@@ -6,6 +6,7 @@ module Bundler
   # be seeded with what we're given from the source's abbreviated index - the
   # full specification will only be fetched when necessary.
   class RemoteSpecification
+    include MatchRemoteMetadata
     include MatchPlatform
     include Comparable
 
@@ -28,13 +29,6 @@ module Bundler
       @platform = _remote_specification.platform
     end
 
-    # A fallback is included because the original version of the specification
-    # API didn't include that field, so some marshalled specs in the index have it
-    # set to +nil+.
-    def required_rubygems_version
-      @required_rubygems_version ||= _remote_specification.required_rubygems_version || Gem::Requirement.default
-    end
-
     def full_name
       if @original_platform == Gem::Platform::RUBY
         "#{@name}-#{@version}"
diff --git a/lib/bundler/resolver.rb b/lib/bundler/resolver.rb
index ca1bdbda7b..e382319112 100644
--- a/lib/bundler/resolver.rb
+++ b/lib/bundler/resolver.rb
@@ -7,6 +7,8 @@ module Bundler
 
     include GemHelpers
 
+    attr_writer :platforms
+
     # Figures out the best possible configuration of gems that satisfies
     # the list of passed dependencies and any child dependencies without
     # causing any gem activation errors.
@@ -19,41 +21,48 @@ module Bundler
     #   collection of gemspecs is returned. Otherwise, nil is returned.
     def self.resolve(requirements, source_requirements = {}, base = [], gem_version_promoter = GemVersionPromoter.new, additional_base_requirements = [], platforms = nil)
       base = SpecSet.new(base) unless base.is_a?(SpecSet)
-      metadata_requirements, regular_requirements = requirements.partition {|dep| dep.name.end_with?("\0") }
-      resolver = new(source_requirements, base, gem_version_promoter, additional_base_requirements, platforms, metadata_requirements)
-      result = resolver.start(requirements)
-      SpecSet.new(SpecSet.new(result).for(regular_requirements, false, platforms))
+      resolver = new(source_requirements, base, gem_version_promoter, additional_base_requirements, platforms)
+      resolver.start(requirements)
     end
 
-    def initialize(source_requirements, base, gem_version_promoter, additional_base_requirements, platforms, metadata_requirements)
+    def initialize(source_requirements, base, gem_version_promoter, additional_base_requirements, platforms)
       @source_requirements = source_requirements
-      @metadata_requirements = metadata_requirements
       @base = base
       @resolver = Molinillo::Resolver.new(self, self)
+      @results_for = {}
       @search_for = {}
-      @base_dg = Molinillo::DependencyGraph.new
-      base.each do |ls|
-        dep = Dependency.new(ls.name, ls.version)
-        @base_dg.add_vertex(ls.name, DepProxy.get_proxy(dep, ls.platform), true)
-      end
-      additional_base_requirements.each {|d| @base_dg.add_vertex(d.name, d) }
-      @platforms = platforms.reject {|p| p != Gem::Platform::RUBY && (platforms - [p]).any? {|pl| generic(pl) == p } }
+      @additional_base_requirements = additional_base_requirements
+      @platforms = platforms
       @resolving_only_for_ruby = platforms == [Gem::Platform::RUBY]
       @gem_version_promoter = gem_version_promoter
       @use_gvp = Bundler.feature_flag.use_gem_version_promoter_for_major_updates? || !@gem_version_promoter.major?
     end
 
-    def start(requirements)
+    def start(requirements, exclude_specs: [])
+      @metadata_requirements, regular_requirements = requirements.partition {|dep| dep.name.end_with?("\0") }
+
+      exclude_specs.each do |spec|
+        remove_from_candidates(spec)
+      end
+
+      @base_dg = Molinillo::DependencyGraph.new
+      @base.each do |ls|
+        dep = Dependency.new(ls.name, ls.version)
+        @base_dg.add_vertex(ls.name, DepProxy.get_proxy(dep, ls.platform), true)
+      end
+      @additional_base_requirements.each {|d| @base_dg.add_vertex(d.name, d) }
+
       @gem_version_promoter.prerelease_specified = @prerelease_specified = {}
       requirements.each {|dep| @prerelease_specified[dep.name] ||= dep.prerelease? }
 
       verify_gemfile_dependencies_are_found!(requirements)
-      dg = @resolver.resolve(requirements, @base_dg)
-      dg.
+      result = @resolver.resolve(requirements, @base_dg).
         map(&:payload).
         reject {|sg| sg.name.end_with?("\0") }.
         map(&:to_specs).
         flatten
+
+      SpecSet.new(SpecSet.new(result).for(regular_requirements, false, @platforms))
     rescue Molinillo::VersionConflict => e
       message = version_conflict_message(e)
       raise VersionConflict.new(e.conflicts.keys.uniq, message)
@@ -177,7 +186,7 @@ module Bundler
     end
 
     def results_for(dependency)
-      index_for(dependency).search(dependency)
+      @results_for[dependency] ||= index_for(dependency).search(dependency)
     end
 
     def name_for(dependency)
@@ -228,6 +237,19 @@ module Bundler
 
     private
 
+    def remove_from_candidates(spec)
+      @base.delete(spec)
+      @gem_version_promoter.reset
+
+      @results_for.keys.each do |dep|
+        next unless dep.name == spec.name
+
+        @results_for[dep].reject {|s| s.name == spec.name && s.version == spec.version }
+      end
+
+      @search_for = {}
+    end
+
     # returns an integer \in (-\infty, 0]
     # a number closer to 0 means the dependency is less constraining
     #
diff --git a/lib/bundler/resolver/spec_group.rb b/lib/bundler/resolver/spec_group.rb
index 4de5b91aa6..4e5b0082d3 100644
--- a/lib/bundler/resolver/spec_group.rb
+++ b/lib/bundler/resolver/spec_group.rb
@@ -97,14 +97,17 @@ module Bundler
       def metadata_dependencies(platform)
         spec = @specs[platform].first
         return [] if spec.is_a?(LazySpecification)
-        dependencies = []
-        unless spec.required_ruby_version.none?
-          dependencies << DepProxy.get_proxy(Dependency.new("Ruby\0", spec.required_ruby_version), platform)
-        end
-        unless spec.required_rubygems_version.none?
-          dependencies << DepProxy.get_proxy(Dependency.new("RubyGems\0", spec.required_rubygems_version), platform)
-        end
-        dependencies
+
+        [
+          metadata_dependency("Ruby", spec.required_ruby_version, platform),
+          metadata_dependency("RubyGems", spec.required_rubygems_version, platform),
+        ].compact
+      end
+
+      def metadata_dependency(name, requirement, platform)
+        return if requirement.nil? || requirement.none?
+
+        DepProxy.get_proxy(Dependency.new("#{name}\0", requirement), platform)
       end
     end
   end
diff --git a/lib/bundler/rubygems_ext.rb b/lib/bundler/rubygems_ext.rb
index 938c58e64d..d976170f12 100644
--- a/lib/bundler/rubygems_ext.rb
+++ b/lib/bundler/rubygems_ext.rb
@@ -15,6 +15,7 @@ require "rubygems/specification"
 # `Gem::Source` from the redefined `Gem::Specification#source`.
 require "rubygems/source"
 
+require_relative "match_metadata"
 require_relative "match_platform"
 
 # Cherry-pick fixes to `Gem.ruby_version` to be useful for modern Bundler
@@ -28,6 +29,7 @@ end
 
 module Gem
   class Specification
+    include ::Bundler::MatchMetadata
     include ::Bundler::MatchPlatform
 
     attr_accessor :remote, :location, :relative_loaded_from
@@ -235,6 +237,32 @@ module Gem
     MINGW = Gem::Platform.new("x86-mingw32")
     X64_MINGW = [Gem::Platform.new("x64-mingw32"),
                  Gem::Platform.new("x64-mingw-ucrt")].freeze
+
+    if Gem::Platform.new("x86_64-linux-musl") === Gem::Platform.new("x86_64-linux")
+      remove_method :===
+
+      def ===(other)
+        return nil unless Gem::Platform === other
+
+        # universal-mingw32 matches x64-mingw-ucrt
+        return true if (@cpu == "universal" || other.cpu == "universal") &&
+                       @os.start_with?("mingw") && other.os.start_with?("mingw")
+
+        # cpu
+        ([nil,"universal"].include?(@cpu) || [nil, "universal"].include?(other.cpu) || @cpu == other.cpu ||
+        (@cpu == "arm" && other.cpu.start_with?("arm"))) &&
+
+          # os
+          @os == other.os &&
+
+          # version
+          (
+            (@os != "linux" && (@version.nil? || other.version.nil?)) ||
+            (@os == "linux" && ((@version.nil? && ["gnu", "musl"].include?(other.version)) || (@version == "gnu" && other.version.nil?))) ||
+            @version == other.version
+          )
+      end
+    end
   end
 
   Platform.singleton_class.module_eval do
diff --git a/lib/bundler/spec_set.rb b/lib/bundler/spec_set.rb
index 14733269d6..4965ca9e60 100644
--- a/lib/bundler/spec_set.rb
+++ b/lib/bundler/spec_set.rb
@@ -7,8 +7,11 @@ module Bundler
     include Enumerable
     include TSort
 
-    def initialize(specs)
+    attr_reader :incomplete_specs
+
+    def initialize(specs, incomplete_specs = [])
       @specs = specs
+      @incomplete_specs = incomplete_specs
     end
 
     def for(dependencies, check = false, platforms = [nil])
@@ -19,7 +22,10 @@ module Bundler
       loop do
         break unless dep = deps.shift
 
-        key = [dep[0].name, dep[1]]
+        name = dep[0].name
+        platform = dep[1]
+
+        key = [name, platform]
         next if handled.key?(key)
 
         handled[key] = true
@@ -33,7 +39,7 @@ module Bundler
             deps << [d, dep[1]]
           end
         elsif check
-          specs << IncompleteSpecification.new(*key)
+          @incomplete_specs += lookup[name]
         end
       end
 
@@ -51,6 +57,12 @@ module Bundler
       @sorted = nil
     end
 
+    def delete(spec)
+      @specs.delete(spec)
+      @lookup = nil
+      @sorted = nil
+    end
+
     def sort!
       self
     end
@@ -66,7 +78,7 @@ module Bundler
     def materialize(deps)
       materialized = self.for(deps, true)
 
-      SpecSet.new(materialized)
+      SpecSet.new(materialized, incomplete_specs)
     end
 
     # Materialize for all the specs in the spec set, regardless of what platform they're for
@@ -83,17 +95,15 @@ module Bundler
     end
 
     def incomplete_ruby_specs?(deps)
-      self.class.new(self.for(deps, true, [Gem::Platform::RUBY])).incomplete_specs.any?
+      self.for(deps, true, [Gem::Platform::RUBY])
+
+      @incomplete_specs.any?
     end
 
     def missing_specs
       @specs.select {|s| s.is_a?(LazySpecification) }
     end
 
-    def incomplete_specs
-      @specs.select {|s| s.is_a?(IncompleteSpecification) }
-    end
-
     def merge(set)
       arr = sorted.dup
       set.each do |set_spec|
diff --git a/lib/bundler/version.rb b/lib/bundler/version.rb
index f15165f86d..a37c989aa8 100644
--- a/lib/bundler/version.rb
+++ b/lib/bundler/version.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: false
 
 module Bundler
-  VERSION = "2.3.20".freeze
+  VERSION = "2.3.21".freeze
 
   def self.bundler_major_version
     @bundler_major_version ||= VERSION.split(".").first.to_i
diff --git a/lib/rubygems.rb b/lib/rubygems.rb
index 616428475f..afe9a73b9c 100644
--- a/lib/rubygems.rb
+++ b/lib/rubygems.rb
@@ -8,7 +8,7 @@
 require "rbconfig"
 
 module Gem
-  VERSION = "3.3.20".freeze
+  VERSION = "3.3.21".freeze
 end
 
 # Must be first since it unloads the prelude from 1.9.2
diff --git a/lib/rubygems/platform.rb b/lib/rubygems/platform.rb
index ed3571dbff..8c5e7993ca 100644
--- a/lib/rubygems/platform.rb
+++ b/lib/rubygems/platform.rb
@@ -25,7 +25,7 @@ class Gem::Platform
     platforms.any? do |local_platform|
       platform.nil? ||
         local_platform == platform ||
-        (local_platform != Gem::Platform::RUBY && local_platform =~ platform)
+        (local_platform != Gem::Platform::RUBY && platform =~ local_platform)
     end
   end
   private_class_method :match_platforms?
@@ -70,7 +70,7 @@ class Gem::Platform
     when String then
       arch = arch.split "-"
 
-      if arch.length > 2 && arch.last !~ (/\d/) # reassemble x86-linux-gnu
+      if arch.length > 2 && arch.last !~ /\d+(\.\d+)?$/ # reassemble x86-linux-{libc}
         extra = arch.pop
         arch.last << "-#{extra}"
       end
@@ -102,7 +102,7 @@ class Gem::Platform
       when /^dalvik(\d+)?$/ then        [ "dalvik",    $1  ]
       when /^dotnet$/ then              [ "dotnet",    nil ]
       when /^dotnet([\d.]*)/ then       [ "dotnet",    $1  ]
-      when /linux-?((?!gnu)\w+)?/ then  [ "linux",     $1  ]
+      when /linux-?(\w+)?/ then         [ "linux",     $1  ]
       when /mingw32/ then               [ "mingw32",   nil ]
       when /mingw-?(\w+)?/ then         [ "mingw",     $1  ]
       when /(mswin\d+)(\_(\d+))?/ then
@@ -151,10 +151,17 @@ class Gem::Platform
   ##
   # Does +other+ match this platform?  Two platforms match if they have the
   # same CPU, or either has a CPU of 'universal', they have the same OS, and
-  # they have the same version, or either has no version.
+  # they have the same version, or either one has no version
   #
   # Additionally, the platform will match if the local CPU is 'arm' and the
   # other CPU starts with "arm" (for generic ARM family support).
+  #
+  # Of note, this method is not commutative. Indeed the OS 'linux' has a
+  # special case: the version is the libc name, yet while "no version" stands
+  # as a wildcard for a binary gem platform (as for other OSes), for the
+  # runtime platform "no version" stands for 'gnu'. To be able to disinguish
+  # these, the method receiver is the gem platform, while the argument is
+  # the runtime platform.
 
   def ===(other)
     return nil unless Gem::Platform === other
@@ -171,7 +178,11 @@ class Gem::Platform
       @os == other.os &&
 
       # version
-      (@version.nil? || other.version.nil? || @version == other.version)
+      (
+        (@os != "linux" && (@version.nil? || other.version.nil?)) ||
+        (@os == "linux" && ((@version.nil? && ["gnu", "musl"].include?(other.version)) || (@version == "gnu" && other.version.nil?))) ||
+        @version == other.version
+      )
   end
 
   ##
diff --git a/spec/bundler/bundler/bundler_spec.rb b/spec/bundler/bundler/bundler_spec.rb
index aeadcf9720..9e79bc165f 100644
--- a/spec/bundler/bundler/bundler_spec.rb
+++ b/spec/bundler/bundler/bundler_spec.rb
@@ -167,9 +167,9 @@ RSpec.describe Bundler do
         allow(::Bundler::FileUtils).to receive(:remove_entry_secure).and_raise(ArgumentError)
         allow(File).to receive(:world_writable?).and_return(true)
         message = <<EOF
-It is a security vulnerability to allow your home directory to be world-writable, and bundler can not continue.
+It is a security vulnerability to allow your home directory to be world-writable, and bundler cannot continue.
 You should probably consider fixing this issue by running `chmod o-w ~` on *nix.
-Please refer to https://ruby-doc.org/stdlib-2.1.2/libdoc/fileutils/rdoc/FileUtils.html#method-c-remove_entry_secure for details.
+Please refer to https://ruby-doc.org/stdlib-3.1.2/libdoc/fileutils/rdoc/FileUtils.html#method-c-remove_entry_secure for details.
 EOF
         expect(bundler_ui).to receive(:warn).with(message)
         expect { Bundler.send(:rm_rf, bundled_app) }.to raise_error(Bundler::PathError)
diff --git a/spec/bundler/commands/init_spec.rb b/spec/bundler/commands/init_spec.rb
index 683a453c7d..eaf8fa170a 100644
--- a/spec/bundler/commands/init_spec.rb
+++ b/spec/bundler/commands/init_spec.rb
@@ -42,7 +42,7 @@ RSpec.describe "bundle init" do
   context "when the dir is not writable by the current user" do
     let(:subdir) { "child_dir" }
 
-    it "notifies the user that it can not write to it" do
+    it "notifies the user that it cannot write to it" do
       FileUtils.mkdir bundled_app(subdir)
       # chmod a-w it
       mode = File.stat(bundled_app(subdir)).mode ^ 0o222
diff --git a/spec/bundler/commands/platform_spec.rb b/spec/bundler/commands/platform_spec.rb
index 0b964eac8c..4e8e3946fe 100644
--- a/spec/bundler/commands/platform_spec.rb
+++ b/spec/bundler/commands/platform_spec.rb
@@ -234,6 +234,29 @@ G
       expect(out).to eq("ruby 1.0.0")
     end
 
+    it "handles when there is a lockfile with no requirement" do
+      gemfile <<-G
+        source "#{file_uri_for(gem_repo1)}"
+      G
+
+      lockfile <<-L
+        GEM
+          remote: #{file_uri_for(gem_repo1)}/
+          specs:
+
+        PLATFORMS
+          ruby
+
+        DEPENDENCIES
+
+        BUNDLED WITH
+           #{Bundler::VERSION}
+      L
+
+      bundle "platform --ruby"
+      expect(out).to eq("No ruby version specified")
+    end
+
     it "handles when there is a requirement in the gemfile" do
       gemfile <<-G
         source "#{file_uri_for(gem_repo1)}"
diff --git a/spec/bundler/commands/remove_spec.rb b/spec/bundler/commands/remove_spec.rb
index 093130f7d5..d757e0be4b 100644
--- a/spec/bundler/commands/remove_spec.rb
+++ b/spec/bundler/commands/remove_spec.rb
@@ -522,7 +522,7 @@ RSpec.describe "bundle remove" do
       end
     end
 
-    context "when gems can not be removed from other gemfile" do
+    context "when gems cannot be removed from other gemfile" do
       it "shows error" do
         create_file "Gemfile-other", <<-G
           gem "rails"; gem "rack"
@@ -574,7 +574,7 @@ RSpec.describe "bundle remove" do
     end
 
     context "when gem present in gemfiles but could not be removed from one from one of them" do
-      it "removes gem which can be removed and shows warning for file from which it can not be removed" do
+      it "removes gem which can be removed and shows warning for file from which it cannot be removed" do
         create_file "Gemfile-other", <<-G
           gem "rack"
         G
diff --git a/spec/bundler/commands/update_spec.rb b/spec/bundler/commands/update_spec.rb
index 8ca537ac10..11ff49bf89 100644
--- a/spec/bundler/commands/update_spec.rb
+++ b/spec/bundler/commands/update_spec.rb
@@ -301,6 +301,66 @@ RSpec.describe "bundle update" do
       expect(lockfile).to eq(previous_lockfile)
     end
 
+    it "does not downgrade direct dependencies when run with --conservative" do
+      build_repo4 do
+        build_gem "oauth2", "2.0.6" do |s|
+          s.add_dependency "faraday", ">= 0.17.3", "< 3.0"
+        end
+
+        build_gem "oauth2", "1.4.10" do |s|
+          s.add_dependency "faraday", ">= 0.17.3", "< 3.0"
+          s.add_dependency "multi_json", "~> 1.3"
+        end
+
+        build_gem "faraday", "2.5.2"
+
+        build_gem "multi_json", "1.15.0"
+
+        build_gem "quickbooks-ruby", "1.0.19" do |s|
+          s.add_dependency "oauth2", "~> 1.4"
+        end
+
+        build_gem "quickbooks-ruby", "0.1.9" do |s|
+          s.add_dependency "oauth2"
+        end
+      end
+
+      gemfile <<-G
+        source "#{file_uri_for(gem_repo4)}"
+
+        gem "oauth2"
+        gem "quickbooks-ruby"
+      G
+
+      lockfile <<~L
+        GEM
+          remote: #{file_uri_for(gem_repo4)}/
+          specs:
+            faraday (2.5.2)
+            multi_json (1.15.0)
+            oauth2 (1.4.10)
+              faraday (>= 0.17.3, < 3.0)
+              multi_json (~> 1.3)
+            quickbooks-ruby (1.0.19)
+              oauth2 (~> 1.4)
+
+        PLATFORMS
+          #{lockfile_platforms}
+
+        DEPENDENCIES
+          oauth2
+          quickbooks-ruby
+
+        BUNDLED WITH
+           #{Bundler::VERSION}
+      L
+
+      bundle "update --conservative --verbose"
+
+      expect(out).not_to include("Installing quickbooks-ruby 0.1.9")
+      expect(out).to include("Installing quickbooks-ruby 1.0.19").and include("Installing oauth2 1.4.10")
+    end
+
     it "does not downgrade indirect dependencies unnecessarily" do
       build_repo4 do
         build_gem "a" do |s|
diff --git a/spec/bundler/install/gemfile/specific_platform_spec.rb b/spec/bundler/install/gemfile/specific_platform_spec.rb
index fe1c3b71fe..bb5526203f 100644
--- a/spec/bundler/install/gemfile/specific_platform_spec.rb
+++ b/spec/bundler/install/gemfile/specific_platform_spec.rb
@@ -445,6 +445,47 @@ RSpec.describe "bundle install with specific platforms" do
     L
   end
 
+  it "does not remove ruby if gems for other platforms, and not present in the lockfile, exist in the Gemfile" do
+    build_repo4 do
+      build_gem "nokogiri", "1.13.8"
+      build_gem "nokogiri", "1.13.8" do |s|
+        s.platform = Gem::Platform.local
+      end
+    end
+
+    gemfile <<~G
+      source "#{file_uri_for(gem_repo4)}"
+
+      gem "nokogiri"
+
+      gem "tzinfo", "~> 1.2", platform: :#{not_local_tag}
+    G
+
+    original_lockfile = <<~L
+      GEM
+        remote: #{file_uri_for(gem_repo4)}/
+        specs:
+          nokogiri (1.13.8)
+          nokogiri (1.13.8-#{Gem::Platform.local})
+
+      PLATFORMS
+        #{lockfile_platforms_for([specific_local_platform, "ruby"])}
+
+      DEPENDENCIES
+        nokogiri
+        tzinfo (~> 1.2)
+
+      BUNDLED WITH
+         #{Bundler::VERSION}
+    L
+
+    lockfile original_lockfile
+
+    bundle "lock --update"
+
+    expect(lockfile).to eq(original_lockfile)
+  end
+
   it "can fallback to a source gem when platform gems are incompatible with current ruby version" do
     setup_multiplatform_gem_with_source_gem
 
diff --git a/spec/bundler/install/gems/dependency_api_spec.rb b/spec/bundler/install/gems/dependency_api_spec.rb
index 79317a7fad..a3c5bc32aa 100644
--- a/spec/bundler/install/gems/dependency_api_spec.rb
+++ b/spec/bundler/install/gems/dependency_api_spec.rb
@@ -443,6 +443,22 @@ RSpec.describe "gemcutter's dependency API" do
     expect(the_bundle).to include_gems "back_deps 1.0"
   end
 
+  it "does not fetch all marshaled specs" do
+    build_repo2 do
+      build_gem "foo", "1.0"
+      build_gem "foo", "2.0"
+    end
+
+    install_gemfile <<-G, :artifice => "endpoint", :env => { "BUNDLER_SPEC_GEM_REPO" => gem_repo2.to_s }, :verbose => true
+      source "#{source_uri}"
+
+      gem "foo"
+    G
+
+    expect(out).to include("foo-2.0.gemspec.rz")
+    expect(out).not_to include("foo-1.0.gemspec.rz")
+  end
+
   it "does not refetch if the only unmet dependency is bundler" do
     build_repo2 do
       build_gem "bundler_dep" do |s|
diff --git a/spec/bundler/install/gems/resolving_spec.rb b/spec/bundler/install/gems/resolving_spec.rb
index 9c0d6bfe56..9405f146b9 100644
--- a/spec/bundler/install/gems/resolving_spec.rb
+++ b/spec/bundler/install/gems/resolving_spec.rb
@@ -305,6 +305,77 @@ RSpec.describe "bundle install with install-time dependencies" do
         end
       end
 
+      context "in a transitive dependencies in a lockfile" do
+        before do
+          build_repo2 do
+            build_gem "rubocop", "1.28.2" do |s|
+              s.required_ruby_version = ">= #{current_ruby_minor}"
+
+              s.add_dependency "rubocop-ast", ">= 1.17.0", "< 2.0"
+            end
+
+            build_gem "rubocop", "1.35.0" do |s|
+              s.required_ruby_version = ">= #{next_ruby_minor}"
+
+              s.add_dependency "rubocop-ast", ">= 1.20.1", "< 2.0"
+            end
+
+            build_gem "rubocop-ast", "1.17.0" do |s|
+              s.required_ruby_version = ">= #{current_ruby_minor}"
+            end
+
+            build_gem "rubocop-ast", "1.21.0" do |s|
+              s.required_ruby_version = ">= #{next_ruby_minor}"
+            end
+          end
+
+          gemfile <<-G
+            source "http://localgemserver.test/"
+            gem 'rubocop'
+          G
+
+          lockfile <<~L
+            GEM
+              remote: http://localgemserver.test/
+              specs:
+                rubocop (1.35.0)
+                  rubocop-ast (>= 1.20.1, < 2.0)
+                rubocop-ast (1.21.0)
+
+            PLATFORMS
+              #{lockfile_platforms}
+
+            DEPENDENCIES
+              parallel_tests
+
+            BUNDLED WITH
+               #{Bundler::VERSION}
+          L
+        end
+
+        it "automatically updates lockfile to use the older compatible versions" do
+          bundle "install --verbose", :artifice => "compact_index", :env => { "BUNDLER_SPEC_GEM_REPO" => gem_repo2.to_s }
+
+          expect(lockfile).to eq <<~L
+            GEM
+              remote: http://localgemserver.test/
+              specs:
+                rubocop (1.28.2)
+                  rubocop-ast (>= 1.17.0, < 2.0)
+                rubocop-ast (1.17.0)
+
+            PLATFORMS
+              #{lockfile_platforms}
+
+            DEPENDENCIES
+              rubocop
+
+            BUNDLED WITH
+               #{Bundler::VERSION}
+          L
+        end
+      end
+
       it "gives a meaningful error on ruby version mismatches between dependencies" do
         build_repo4 do
           build_gem "requires-old-ruby" do |s|
diff --git a/spec/bundler/plugins/install_spec.rb b/spec/bundler/plugins/install_spec.rb
index 009516260a..efee5fdd23 100644
--- a/spec/bundler/plugins/install_spec.rb
+++ b/spec/bundler/plugins/install_spec.rb
@@ -32,7 +32,8 @@ RSpec.describe "bundler plugin install" do
   it "shows help when --help flag is given" do
     bundle "plugin install --help"
 
-    expect(out).to include("bundle plugin install PLUGINS    # Install the plugin from the source")
+    # The help message defined in ../../lib/bundler/man/bundle-plugin.1.ronn will be output.
+    expect(out).to include("You can install, uninstall, and list plugin(s)")
   end
 
   context "plugin is already installed" do
@@ -84,6 +85,26 @@ RSpec.describe "bundler plugin install" do
     expect(out).to include("Using foo 1.1")
   end
 
+  it "installs when --branch specified" do
+    bundle "plugin install foo --branch main --source #{file_uri_for(gem_repo2)}"
+
+    expect(out).to include("Installed plugin foo")
+  end
+
+  it "installs when --ref specified" do
+    bundle "plugin install foo --ref v1.2.3 --source #{file_uri_for(gem_repo2)}"
+
+    expect(out).to include("Installed plugin foo")
+  end
+
+  it "raises error when both --branch and --ref options are specified" do
+    bundle "plugin install foo --source #{file_uri_for(gem_repo2)} --branch main --ref v1.2.3", :raise_on_error => false
+
+    expect(out).not_to include("Installed plugin foo")
+
+    expect(err).to include("You cannot specify `--branch` and `--ref` at the same time.")
+  end
+
   it "works with different load paths" do
     build_repo2 do
       build_plugin "testing" do |s|
diff --git a/spec/bundler/resolver/platform_spec.rb b/spec/bundler/resolver/platform_spec.rb
index 8eaed4220a..418293365c 100644
--- a/spec/bundler/resolver/platform_spec.rb
+++ b/spec/bundler/resolver/platform_spec.rb
@@ -82,6 +82,79 @@ RSpec.describe "Resolving platform craziness" do
     should_resolve_as %w[foo-1.0.0-x64-mingw32]
   end
 
+  describe "on a linux platform", :rubygems => ">= 3.1.0.pre.1" do
+    # Ruby's platform is *-linux => platform's libc is glibc, so not musl
+    # Ruby's platform is *-linux-musl => platform's libc is musl, so not glibc
+    # Gem's platform is *-linux => gem is glibc + maybe musl compatible
+    # Gem's platform is *-linux-musl => gem is musl compatible but not glibc
+
+    it "favors the platform version-specific gem on a version-specifying linux platform" do
+      @index = build_index do
+        gem "foo", "1.0.0"
+        gem "foo", "1.0.0", "x86_64-linux"
+        gem "foo", "1.0.0", "x86_64-linux-musl"
+      end
+      dep "foo"
+      platforms "x86_64-linux-musl"
+
+      should_resolve_as %w[foo-1.0.0-x86_64-linux-musl]
+    end
+
+    it "favors the version-less gem over the version-specific gem on a gnu linux platform" do
+      @index = build_index do
+        gem "foo", "1.0.0"
+        gem "foo", "1.0.0", "x86_64-linux"
+        gem "foo", "1.0.0", "x86_64-linux-musl"
+      end
+      dep "foo"
+      platforms "x86_64-linux"
+
+      should_resolve_as %w[foo-1.0.0-x86_64-linux]
+    end
+
+    it "ignores the platform version-specific gem on a gnu linux platform" do
+      @index = build_index do
+        gem "foo", "1.0.0", "x86_64-linux-musl"
+      end
+      dep "foo"
+      platforms "x86_64-linux"
+
+      should_not_resolve
+    end
+
+    it "falls back to the platform version-less gem on a linux platform with a version" do
+      @index = build_index do
+        gem "foo", "1.0.0"
+        gem "foo", "1.0.0", "x86_64-linux"
+      end
+      dep "foo"
+      platforms "x86_64-linux-musl"
+
+      should_resolve_as %w[foo-1.0.0-x86_64-linux]
+    end
+
+    it "falls back to the ruby platform gem on a gnu linux platform when only a version-specifying gem is available" do
+      @index = build_index do
+        gem "foo", "1.0.0"
+        gem "foo", "1.0.0", "x86_64-linux-musl"
+      end
+      dep "foo"
+      platforms "x86_64-linux"
+
+      should_resolve_as %w[foo-1.0.0]
+    end
+
+    it "falls back to the platform version-less gem on a version-specifying linux platform and no ruby platform gem is available" do
+      @index = build_index do
+        gem "foo", "1.0.0", "x86_64-linux"
+      end
+      dep "foo"
+      platforms "x86_64-linux-musl"
+
+      should_resolve_as %w[foo-1.0.0-x86_64-linux]
+    end
+  end
+
   it "takes the latest ruby gem if the platform specific gem doesn't match the required_ruby_version" do
     @index = build_index do
       gem "foo", "1.0.0"
diff --git a/spec/bundler/runtime/inline_spec.rb b/spec/bundler/runtime/inline_spec.rb
index dd22c86f90..e3cf5020ec 100644
--- a/spec/bundler/runtime/inline_spec.rb
+++ b/spec/bundler/runtime/inline_spec.rb
@@ -355,6 +355,20 @@ RSpec.describe "bundler/inline#gemfile" do
     expect(err).to be_empty
   end
 
+  it "still installs if the application has `bundle package` no_install config set" do
+    bundle "config set --local no_install true"
+
+    script <<-RUBY
+      gemfile do
+        source "#{file_uri_for(gem_repo1)}"
+        gem "rack"
+      end
+    RUBY
+
+    expect(last_command).to be_success
+    expect(system_gem_path("gems/rack-1.0.0")).to exist
+  end
+
   it "preserves previous BUNDLE_GEMFILE value" do
     ENV["BUNDLE_GEMFILE"] = ""
     script <<-RUBY
diff --git a/spec/bundler/support/artifice/compact_index_api_missing.rb b/spec/bundler/support/artifice/compact_index_api_missing.rb
index 6514fde01e..2fd8b6d2e9 100644
--- a/spec/bundler/support/artifice/compact_index_api_missing.rb
+++ b/spec/bundler/support/artifice/compact_index_api_missing.rb
@@ -6,12 +6,7 @@ Artifice.deactivate
 
 class CompactIndexApiMissing < CompactIndexAPI
   get "/fetch/actual/gem/:id" do
-    warn params[:id]
-    if params[:id] == "rack-1.0.gemspec.rz"
-      halt 404
-    else
-      File.binread("#{gem_repo2}/quick/Marshal.4.8/#{params[:id]}")
-    end
+    halt 404
   end
 end
 
diff --git a/spec/bundler/support/indexes.rb b/spec/bundler/support/indexes.rb
index 55d798a90a..c496679ee6 100644
--- a/spec/bundler/support/indexes.rb
+++ b/spec/bundler/support/indexes.rb
@@ -33,6 +33,10 @@ module Spec
       Bundler::Resolver.resolve(deps, source_requirements, *args)
     end
 
+    def should_not_resolve
+      expect { resolve }.to raise_error(Bundler::GemNotFound)
+    end
+
     def should_resolve_as(specs)
       got = resolve
       got = got.map(&:full_name).sort
diff --git a/test/rubygems/test_gem_ext_cargo_builder/custom_name/Cargo.lock b/test/rubygems/test_gem_ext_cargo_builder/custom_name/Cargo.lock
index da09e717f0..0f1fa7c430 100644
--- a/test/rubygems/test_gem_ext_cargo_builder/custom_name/Cargo.lock
+++ b/test/rubygems/test_gem_ext_cargo_builder/custom_name/Cargo.lock
@@ -160,9 +160,9 @@ dependencies = [
 
 [[package]]
 name = "rb-sys"
-version = "0.9.29"
+version = "0.9.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0317cb843cdeef14c5622917c55c0a170cee31348eb600c4a1683fb8c9e87e7a"
+checksum = "24b22a374fc2e92eb6f49d7efe4eb7663655c6e9455d9259ed3342cc1599da85"
 dependencies = [
  "bindgen",
  "linkify",
@@ -171,9 +171,9 @@ dependencies = [
 
 [[package]]
 name = "rb-sys-build"
-version = "0.9.29"
+version = "0.9.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4b8274327aecb7edcff86e290d9cbe7b572b7889c1cfc7476358f4831f78ce5"
+checksum = "3cd23b6dd929b7d50ccb35a6d3aa77dec364328ab9cb304dd32c629332491671"
 dependencies = [
  "regex",
  "shell-words",
diff --git a/test/rubygems/test_gem_ext_cargo_builder/custom_name/Cargo.toml b/test/rubygems/test_gem_ext_cargo_builder/custom_name/Cargo.toml
index 2a215a55dd..c9ba5c27bd 100644
--- a/test/rubygems/test_gem_ext_cargo_builder/custom_name/Cargo.toml
+++ b/test/rubygems/test_gem_ext_cargo_builder/custom_name/Cargo.toml
@@ -7,4 +7,4 @@ edition = "2021"
 crate-type = ["cdylib"]
 
 [dependencies]
-rb-sys = { version = "0.9.29", features = ["gem"] }
+rb-sys = { version = "0.9.30", features = ["gem"] }
diff --git a/test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/Cargo.lock b/test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/Cargo.lock
index e351819848..5e602fcf92 100644
--- a/test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/Cargo.lock
+++ b/test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/Cargo.lock
@@ -153,9 +153,9 @@ dependencies = [
 
 [[package]]
 name = "rb-sys"
-version = "0.9.29"
+version = "0.9.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0317cb843cdeef14c5622917c55c0a170cee31348eb600c4a1683fb8c9e87e7a"
+checksum = "24b22a374fc2e92eb6f49d7efe4eb7663655c6e9455d9259ed3342cc1599da85"
 dependencies = [
  "bindgen",
  "linkify",
@@ -164,9 +164,9 @@ dependencies = [
 
 [[package]]
 name = "rb-sys-build"
-version = "0.9.29"
+version = "0.9.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4b8274327aecb7edcff86e290d9cbe7b572b7889c1cfc7476358f4831f78ce5"
+checksum = "3cd23b6dd929b7d50ccb35a6d3aa77dec364328ab9cb304dd32c629332491671"
 dependencies = [
  "regex",
  "shell-words",
diff --git a/test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/Cargo.toml b/test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/Cargo.toml
index 1867db8e66..8e3f623728 100644
--- a/test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/Cargo.toml
+++ b/test/rubygems/test_gem_ext_cargo_builder/rust_ruby_example/Cargo.toml
@@ -7,4 +7,4 @@ edition = "2021"
 crate-type = ["cdylib"]
 
 [dependencies]
-rb-sys = { version = "0.9.29", features = ["gem"] }
+rb-sys = { version = "0.9.30", features = ["gem"] }
diff --git a/test/rubygems/test_gem_platform.rb b/test/rubygems/test_gem_platform.rb
index 0fb5bf59a5..e0e635e533 100644
--- a/test/rubygems/test_gem_platform.rb
+++ b/test/rubygems/test_gem_platform.rb
@@ -119,8 +119,8 @@ class TestGemPlatform < Gem::TestCase
       "i586-linux"             => ["x86",       "linux",     nil],
       "i486-linux"             => ["x86",       "linux",     nil],
       "i386-linux"             => ["x86",       "linux",     nil],
-      "i586-linux-gnu"         => ["x86",       "linux",     nil],
-      "i386-linux-gnu"         => ["x86",       "linux",     nil],
+      "i586-linux-gnu"         => ["x86",       "linux",     "gnu"],
+      "i386-linux-gnu"         => ["x86",       "linux",     "gnu"],
       "i386-mingw32"           => ["x86",       "mingw32",   nil],
       "x64-mingw-ucrt"         => ["x64",       "mingw",     "ucrt"],
       "i386-mswin32"           => ["x86",       "mswin32",   nil],
@@ -135,7 +135,9 @@ class TestGemPlatform < Gem::TestCase
       "i386-solaris2.8"        => ["x86",       "solaris",   "2.8"],
       "mswin32"                => ["x86",       "mswin32",   nil],
       "x86_64-linux"           => ["x86_64",    "linux",     nil],
+      "x86_64-linux-gnu"       => ["x86_64",    "linux",     "gnu"],
       "x86_64-linux-musl"      => ["x86_64",    "linux",     "musl"],
+      "x86_64-linux-uclibc"    => ["x86_64",    "linux",     "uclibc"],
       "x86_64-openbsd3.9"      => ["x86_64",    "openbsd",   "3.9"],
       "x86_64-openbsd4.0"      => ["x86_64",    "openbsd",   "4.0"],
       "x86_64-openbsd"         => ["x86_64",    "openbsd",   nil],
@@ -144,6 +146,7 @@ class TestGemPlatform < Gem::TestCase
     test_cases.each do |arch, expected|
       platform = Gem::Platform.new arch
       assert_equal expected, platform.to_a, arch.inspect
+      assert_equal expected, Gem::Platform.new(platform.to_s).to_a, arch.inspect
     end
   end
 
@@ -262,6 +265,42 @@ class TestGemPlatform < Gem::TestCase
     assert((with_x86_arch === with_nil_arch), "x86 =~ nil")
   end
 
+  def test_nil_version_is_treated_as_any_version
+    x86_darwin_8 = Gem::Platform.new "i686-darwin8.0"
+    x86_darwin_nil = Gem::Platform.new "i686-darwin"
+
+    assert((x86_darwin_8 === x86_darwin_nil), "8.0 =~ nil")
+    assert((x86_darwin_nil === x86_darwin_8), "nil =~ 8.0")
+  end
+
+  def test_nil_version_is_stricter_for_linux_os
+    x86_linux = Gem::Platform.new "i686-linux"
+    x86_linux_gnu = Gem::Platform.new "i686-linux-gnu"
+    x86_linux_musl = Gem::Platform.new "i686-linux-musl"
+    x86_linux_uclibc = Gem::Platform.new "i686-linux-uclibc"
+
+    # a naked linux runtime is implicit gnu, as it represents the common glibc-linked runtime
+    assert(x86_linux === x86_linux_gnu, "linux =~ linux-gnu")
+    assert(x86_linux_gnu === x86_linux, "linux-gnu =~ linux")
+
+    # musl and explicit gnu should differ
+    refute(x86_linux_gnu === x86_linux_musl, "linux-gnu =~ linux-musl")
+    refute(x86_linux_musl === x86_linux_gnu, "linux-musl =~ linux-gnu")
+
+    # explicit libc differ
+    refute(x86_linux_uclibc === x86_linux_musl, "linux-uclibc =~ linux-musl")
+    refute(x86_linux_musl === x86_linux_uclibc, "linux-musl =~ linux-uclibc")
+
+    # musl host runtime accepts libc-generic or statically linked gems...
+    assert(x86_linux === x86_linux_musl, "linux =~ linux-musl")
+    # ...but implicit gnu runtime generally does not accept musl-specific gems
+    refute(x86_linux_musl === x86_linux, "linux-musl =~ linux")
+
+    # other libc are not glibc compatible
+    refute(x86_linux === x86_linux_uclibc, "linux =~ linux-uclibc")
+    refute(x86_linux_uclibc === x86_linux, "linux-uclibc =~ linux")
+  end
+
   def test_equals3_cpu_arm
     arm   = Gem::Platform.new "arm-linux"
     armv5 = Gem::Platform.new "armv5-linux"
diff --git a/test/rubygems/test_gem_resolver.rb b/test/rubygems/test_gem_resolver.rb
index 2271244729..c816d5484b 100644
--- a/test/rubygems/test_gem_resolver.rb
+++ b/test/rubygems/test_gem_resolver.rb
@@ -322,16 +322,15 @@ class TestGemResolver < Gem::TestCase
   def test_picks_best_platform
     is      = Gem::Resolver::IndexSpecification
     unknown = Gem::Platform.new "unknown"
-    a2_p1   = a3_p2 = nil
 
     spec_fetcher do |fetcher|
       fetcher.spec "a", 2
 
-      a2_p1 = fetcher.spec "a", 2 do |s|
+      fetcher.spec "a", 2 do |s|
         s.platform = Gem::Platform.local
       end
 
-      a3_p2 = fetcher.spec "a", 3 do |s|
+      fetcher.spec "a", 3 do |s|
         s.platform = unknown
       end
     end
@@ -357,6 +356,41 @@ class TestGemResolver < Gem::TestCase
     assert_resolves_to [a2_p1.spec], res
   end
 
+  def test_does_not_pick_musl_variants_on_non_musl_linux
+    util_set_arch "aarch64-linux" do
+      is = Gem::Resolver::IndexSpecification
+
+      linux_musl = Gem::Platform.new("aarch64-linux-musl")
+
+      spec_fetcher do |fetcher|
+        fetcher.spec "libv8-node", "15.14.0.1" do |s|
+          s.platform = Gem::Platform.local
+        end
+
+        fetcher.spec "libv8-node", "15.14.0.1" do |s|
+          s.platform = linux_musl
+        end
+      end
+
+      v15 = v("15.14.0.1")
+      source = Gem::Source.new @gem_repo
+
+      s = set
+
+      v15_linux = is.new s, "libv8-node", v15, source, Gem::Platform.local.to_s
+      v15_linux_musl = is.new s, "libv8-node", v15, source, linux_musl.to_s
+
+      s.add v15_linux
+      s.add v15_linux_musl
+
+      ad = make_dep "libv8-node", "= 15.14.0.1"
+
+      res = Gem::Resolver.new([ad], s)
+
+      assert_resolves_to [v15_linux.spec], res
+    end
+  end
+
   def test_only_returns_spec_once
     a1 = util_spec "a", "1", "c" => "= 1"
     b1 = util_spec "b", "1", "c" => "= 1"
diff --git a/tool/bundler/dev_gems.rb.lock b/tool/bundler/dev_gems.rb.lock
index 75d8faf683..994c70d333 100644
--- a/tool/bundler/dev_gems.rb.lock
+++ b/tool/bundler/dev_gems.rb.lock
@@ -53,4 +53,4 @@ DEPENDENCIES
   webrick (~> 1.6)
 
 BUNDLED WITH
-   2.3.20
+   2.3.21
diff --git a/tool/bundler/rubocop_gems.rb.lock b/tool/bundler/rubocop_gems.rb.lock
index 02fdb0b24d..c321d05fc3 100644
--- a/tool/bundler/rubocop_gems.rb.lock
+++ b/tool/bundler/rubocop_gems.rb.lock
@@ -62,4 +62,4 @@ DEPENDENCIES
   test-unit
 
 BUNDLED WITH
-   2.3.20
+   2.3.21
diff --git a/tool/bundler/standard_gems.rb.lock b/tool/bundler/standard_gems.rb.lock
index 570bd99b4c..9f454cf76e 100644
--- a/tool/bundler/standard_gems.rb.lock
+++ b/tool/bundler/standard_gems.rb.lock
@@ -68,4 +68,4 @@ DEPENDENCIES
   test-unit
 
 BUNDLED WITH
-   2.3.20
+   2.3.21
diff --git a/tool/bundler/test_gems.rb.lock b/tool/bundler/test_gems.rb.lock
index 25602cabb2..8203af4c1a 100644
--- a/tool/bundler/test_gems.rb.lock
+++ b/tool/bundler/test_gems.rb.lock
@@ -43,4 +43,4 @@ DEPENDENCIES
   webrick (= 1.7.0)
 
 BUNDLED WITH
-   2.3.20
+   2.3.21