diff --git a/Manifest.txt b/Manifest.txt
index 6152c06b2c08..72b806e54974 100644
--- a/Manifest.txt
+++ b/Manifest.txt
@@ -156,6 +156,7 @@ bundler/lib/bundler/match_platform.rb
 bundler/lib/bundler/match_remote_metadata.rb
 bundler/lib/bundler/materialization.rb
 bundler/lib/bundler/mirror.rb
+bundler/lib/bundler/override.rb
 bundler/lib/bundler/plugin.rb
 bundler/lib/bundler/plugin/api.rb
 bundler/lib/bundler/plugin/api/source.rb
diff --git a/bundler/lib/bundler.rb b/bundler/lib/bundler.rb
index 8bec10c0db87..12dde90fc5d8 100644
--- a/bundler/lib/bundler.rb
+++ b/bundler/lib/bundler.rb
@@ -62,6 +62,7 @@ module Bundler
   autoload :MatchRemoteMetadata,    File.expand_path("bundler/match_remote_metadata", __dir__)
   autoload :Materialization,        File.expand_path("bundler/materialization", __dir__)
   autoload :NULL,                   File.expand_path("bundler/constants", __dir__)
+  autoload :Override,               File.expand_path("bundler/override", __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__)
diff --git a/bundler/lib/bundler/definition.rb b/bundler/lib/bundler/definition.rb
index a620475c18cf..a64b67cb44d0 100644
--- a/bundler/lib/bundler/definition.rb
+++ b/bundler/lib/bundler/definition.rb
@@ -10,13 +10,14 @@ class << self
       attr_accessor :no_lock
     end
 
-    attr_writer :lockfile
+    attr_writer :lockfile, :overrides
 
     attr_reader(
       :dependencies,
       :locked_checksums,
       :locked_deps,
       :locked_gems,
+      :overrides,
       :platforms,
       :ruby_version,
       :lockfile,
@@ -58,7 +59,7 @@ def self.build(gemfile, lockfile, unlock)
     #   to be updated or true if all gems should be updated
     # @param ruby_version [Bundler::RubyVersion, nil] Requested Ruby Version
     # @param optional_groups [Array(String)] A list of optional groups
-    def initialize(lockfile, dependencies, sources, unlock, ruby_version = nil, optional_groups = [], gemfiles = [])
+    def initialize(lockfile, dependencies, sources, unlock, ruby_version = nil, optional_groups = [], gemfiles = [], overrides = [])
       unlock ||= {}
 
       if unlock == true
@@ -88,6 +89,7 @@ def initialize(lockfile, dependencies, sources, unlock, ruby_version = nil, opti
       @specs           = nil
       @ruby_version    = ruby_version
       @gemfiles        = gemfiles
+      @overrides       = overrides
 
       @lockfile               = lockfile
       @lockfile_contents      = String.new
@@ -633,7 +635,20 @@ def resolver
     end
 
     def expanded_dependencies
-      dependencies_with_bundler + metadata_dependencies
+      apply_overrides_to(dependencies_with_bundler) + metadata_dependencies
+    end
+
+    def apply_overrides_to(deps)
+      return deps if @overrides.empty?
+      deps.map {|dep| apply_override_to(dep) }
+    end
+
+    def apply_override_to(dep)
+      override = @overrides.find {|o| o.target == dep.name && o.field == :version }
+      return dep unless override
+      new_dep = dep.dup
+      new_dep.instance_variable_set(:@requirement, override.apply_to(dep.requirement))
+      new_dep
     end
 
     def dependencies_with_bundler
@@ -1029,7 +1044,7 @@ def converge_dependencies
               @locked_specs.delete(locked_specs.select {|s| s.source != dep.source })
             end
 
-            unless dep.matches_spec?(locked_specs.first)
+            unless apply_override_to(dep).matches_spec?(locked_specs.first)
               @gems_to_unlock << name
               dep_changed = true
             end
@@ -1039,9 +1054,25 @@ def converge_dependencies
         @changed_dependencies << name if dep_changed
       end
 
+      converge_overrides_outside_dependencies
+
       @changed_dependencies.any?
     end
 
+    def converge_overrides_outside_dependencies
+      @overrides.each do |override|
+        next unless override.target.is_a?(String)
+
+        name = override.target
+        next if @changed_dependencies.include?(name)
+        next if @dependencies.any? {|d| d.name == name }
+        next if @originally_locked_specs[name].empty?
+
+        @gems_to_unlock << name
+        @changed_dependencies << name
+      end
+    end
+
     # Remove elements from the locked specs that are expired. This will most
     # commonly happen if the Gemfile has changed since the lockfile was last
     # generated
@@ -1273,7 +1304,7 @@ def unlocked_resolution_base
 
     def new_resolution_base(last_resolve:, unlock:)
       new_resolution_platforms = @current_platform_missing ? @new_platforms + [Bundler.local_platform] : @new_platforms
-      Resolver::Base.new(source_requirements, expanded_dependencies, last_resolve, @platforms, locked_specs: @originally_locked_specs, unlock: unlock, prerelease: gem_version_promoter.pre?, prefer_local: @prefer_local, new_platforms: new_resolution_platforms)
+      Resolver::Base.new(source_requirements, expanded_dependencies, last_resolve, @platforms, locked_specs: @originally_locked_specs, unlock: unlock, prerelease: gem_version_promoter.pre?, prefer_local: @prefer_local, new_platforms: new_resolution_platforms, overrides: @overrides)
     end
 
     def new_resolver(base)
diff --git a/bundler/lib/bundler/dsl.rb b/bundler/lib/bundler/dsl.rb
index 6f06c4e91879..c7a7d855eef1 100644
--- a/bundler/lib/bundler/dsl.rb
+++ b/bundler/lib/bundler/dsl.rb
@@ -22,7 +22,7 @@ def self.evaluate(gemfile, lockfile, unlock)
     GITHUB_PULL_REQUEST_URL = %r{\Ahttps://github\.com/([A-Za-z0-9_\-\.]+/[A-Za-z0-9_\-\.]+)/pull/(\d+)\z}
     GITLAB_MERGE_REQUEST_URL = %r{\Ahttps://gitlab\.com/([A-Za-z0-9_\-\./]+)/-/merge_requests/(\d+)\z}
 
-    attr_reader :gemspecs, :gemfile
+    attr_reader :gemspecs, :gemfile, :overrides
     attr_accessor :dependencies
 
     def initialize
@@ -40,6 +40,7 @@ def initialize
       @gemfile              = nil
       @gemfiles             = []
       @lockfile             = nil
+      @overrides            = []
       add_git_sources
     end
 
@@ -184,10 +185,31 @@ def github(repo, options = {})
       with_source(git_source) { yield }
     end
 
+    SUPPORTED_OVERRIDE_FIELDS = [:version].freeze
+    SUPPORTED_OVERRIDE_SYMBOL_OPERATIONS = [:ignore_upper].freeze
+
+    def override(target, **operations)
+      validate_override_target!(target)
+
+      if target == :all && operations.key?(:version)
+        raise ArgumentError, "`override :all, version:` is not allowed; version requirements are per-gem"
+      end
+
+      operations.each do |field, operation|
+        validate_override_field!(field)
+        validate_override_operation!(operation)
+        validate_override_uniqueness!(target, field)
+      end
+
+      operations.each do |field, operation|
+        @overrides << Override.new(target, field, operation)
+      end
+    end
+
     def to_definition(lockfile, unlock)
       check_primary_source_safety
       lockfile = @lockfile unless @lockfile.nil?
-      Definition.new(lockfile, @dependencies, @sources, unlock, @ruby_version, @optional_groups, @gemfiles)
+      Definition.new(lockfile, @dependencies, @sources, unlock, @ruby_version, @optional_groups, @gemfiles, @overrides)
     end
 
     def group(*args, &blk)
@@ -244,6 +266,34 @@ def check_primary_source_safety
 
     private
 
+    def validate_override_target!(target)
+      return if target == :all
+      return if target.is_a?(String)
+      raise ArgumentError, "override target must be :all or a gem name string, got #{target.inspect}"
+    end
+
+    def validate_override_field!(field)
+      return if SUPPORTED_OVERRIDE_FIELDS.include?(field)
+      raise ArgumentError, "unsupported override field `#{field}:`; only `version:` is currently supported"
+    end
+
+    def validate_override_operation!(operation)
+      case operation
+      when String, nil
+        # ok
+      when Symbol
+        return if SUPPORTED_OVERRIDE_SYMBOL_OPERATIONS.include?(operation)
+        raise ArgumentError, "unsupported override operation: #{operation.inspect}"
+      else
+        raise ArgumentError, "override operation must be a String, Symbol, or nil, got #{operation.inspect}"
+      end
+    end
+
+    def validate_override_uniqueness!(target, field)
+      return unless @overrides.any? {|o| o.target == target && o.field == field }
+      raise ArgumentError, "duplicate override for #{target.inspect} `#{field}:`"
+    end
+
     def add_dependency(name, version = nil, options = {})
       options["gemfile"] = @gemfile
       options["source"] ||= @source
diff --git a/bundler/lib/bundler/man/bundle-add.1 b/bundler/lib/bundler/man/bundle-add.1
index f49d8e568c9b..031eef686c94 100644
--- a/bundler/lib/bundler/man/bundle-add.1
+++ b/bundler/lib/bundler/man/bundle-add.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-ADD" "1" "April 2026" ""
+.TH "BUNDLE\-ADD" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-add\fR \- Add gem to the Gemfile and run bundle install
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-binstubs.1 b/bundler/lib/bundler/man/bundle-binstubs.1
index 9dbd4f1d3a1f..246daeae53ed 100644
--- a/bundler/lib/bundler/man/bundle-binstubs.1
+++ b/bundler/lib/bundler/man/bundle-binstubs.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-BINSTUBS" "1" "April 2026" ""
+.TH "BUNDLE\-BINSTUBS" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-binstubs\fR \- Install the binstubs of the listed gems
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-cache.1 b/bundler/lib/bundler/man/bundle-cache.1
index e2052ab0ac16..38ea04796124 100644
--- a/bundler/lib/bundler/man/bundle-cache.1
+++ b/bundler/lib/bundler/man/bundle-cache.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-CACHE" "1" "April 2026" ""
+.TH "BUNDLE\-CACHE" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-cache\fR \- Package your needed \fB\.gem\fR files into your application
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-check.1 b/bundler/lib/bundler/man/bundle-check.1
index 825a2889d57a..6cd474d90ab7 100644
--- a/bundler/lib/bundler/man/bundle-check.1
+++ b/bundler/lib/bundler/man/bundle-check.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-CHECK" "1" "April 2026" ""
+.TH "BUNDLE\-CHECK" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-check\fR \- Verifies if dependencies are satisfied by installed gems
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-clean.1 b/bundler/lib/bundler/man/bundle-clean.1
index 0eae33d08d19..eb90636c1717 100644
--- a/bundler/lib/bundler/man/bundle-clean.1
+++ b/bundler/lib/bundler/man/bundle-clean.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-CLEAN" "1" "April 2026" ""
+.TH "BUNDLE\-CLEAN" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-clean\fR \- Cleans up unused gems in your bundler directory
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-config.1 b/bundler/lib/bundler/man/bundle-config.1
index 8835ae75bd9e..61487ca55e79 100644
--- a/bundler/lib/bundler/man/bundle-config.1
+++ b/bundler/lib/bundler/man/bundle-config.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-CONFIG" "1" "April 2026" ""
+.TH "BUNDLE\-CONFIG" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-config\fR \- Set bundler configuration options
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-console.1 b/bundler/lib/bundler/man/bundle-console.1
index c86b90e3bd23..5d3f65365faa 100644
--- a/bundler/lib/bundler/man/bundle-console.1
+++ b/bundler/lib/bundler/man/bundle-console.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-CONSOLE" "1" "April 2026" ""
+.TH "BUNDLE\-CONSOLE" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-console\fR \- Open an IRB session with the bundle pre\-loaded
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-doctor.1 b/bundler/lib/bundler/man/bundle-doctor.1
index fe9a8a35b9af..4c59871b66ad 100644
--- a/bundler/lib/bundler/man/bundle-doctor.1
+++ b/bundler/lib/bundler/man/bundle-doctor.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-DOCTOR" "1" "April 2026" ""
+.TH "BUNDLE\-DOCTOR" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-doctor\fR \- Checks the bundle for common problems
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-env.1 b/bundler/lib/bundler/man/bundle-env.1
index 29c4ac2a8e21..25fcb648917f 100644
--- a/bundler/lib/bundler/man/bundle-env.1
+++ b/bundler/lib/bundler/man/bundle-env.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-ENV" "1" "April 2026" ""
+.TH "BUNDLE\-ENV" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-env\fR \- Print information about the environment Bundler is running under
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-exec.1 b/bundler/lib/bundler/man/bundle-exec.1
index fec7bee39c33..c3a6a09d578a 100644
--- a/bundler/lib/bundler/man/bundle-exec.1
+++ b/bundler/lib/bundler/man/bundle-exec.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-EXEC" "1" "April 2026" ""
+.TH "BUNDLE\-EXEC" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-exec\fR \- Execute a command in the context of the bundle
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-fund.1 b/bundler/lib/bundler/man/bundle-fund.1
index 2eb07a6c8d8c..caee1f81dd64 100644
--- a/bundler/lib/bundler/man/bundle-fund.1
+++ b/bundler/lib/bundler/man/bundle-fund.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-FUND" "1" "April 2026" ""
+.TH "BUNDLE\-FUND" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-fund\fR \- Lists information about gems seeking funding assistance
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-gem.1 b/bundler/lib/bundler/man/bundle-gem.1
index bdb84faebdd0..87d756824698 100644
--- a/bundler/lib/bundler/man/bundle-gem.1
+++ b/bundler/lib/bundler/man/bundle-gem.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-GEM" "1" "April 2026" ""
+.TH "BUNDLE\-GEM" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-gem\fR \- Generate a project skeleton for creating a rubygem
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-help.1 b/bundler/lib/bundler/man/bundle-help.1
index 6e6ad14624d7..3bcfd047e546 100644
--- a/bundler/lib/bundler/man/bundle-help.1
+++ b/bundler/lib/bundler/man/bundle-help.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-HELP" "1" "April 2026" ""
+.TH "BUNDLE\-HELP" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-help\fR \- Displays detailed help for each subcommand
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-info.1 b/bundler/lib/bundler/man/bundle-info.1
index b18b70309c50..49c2295f8c98 100644
--- a/bundler/lib/bundler/man/bundle-info.1
+++ b/bundler/lib/bundler/man/bundle-info.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-INFO" "1" "April 2026" ""
+.TH "BUNDLE\-INFO" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-info\fR \- Show information for the given gem in your bundle
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-init.1 b/bundler/lib/bundler/man/bundle-init.1
index 5ea1c3b47837..63e2376c3fd3 100644
--- a/bundler/lib/bundler/man/bundle-init.1
+++ b/bundler/lib/bundler/man/bundle-init.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-INIT" "1" "April 2026" ""
+.TH "BUNDLE\-INIT" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-init\fR \- Generates a Gemfile into the current working directory
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-install.1 b/bundler/lib/bundler/man/bundle-install.1
index c2f9bfeea1f7..a764d031ed12 100644
--- a/bundler/lib/bundler/man/bundle-install.1
+++ b/bundler/lib/bundler/man/bundle-install.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-INSTALL" "1" "April 2026" ""
+.TH "BUNDLE\-INSTALL" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-install\fR \- Install the dependencies specified in your Gemfile
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-issue.1 b/bundler/lib/bundler/man/bundle-issue.1
index e99cf67638f3..3af277ef867a 100644
--- a/bundler/lib/bundler/man/bundle-issue.1
+++ b/bundler/lib/bundler/man/bundle-issue.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-ISSUE" "1" "April 2026" ""
+.TH "BUNDLE\-ISSUE" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-issue\fR \- Get help reporting Bundler issues
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-licenses.1 b/bundler/lib/bundler/man/bundle-licenses.1
index eb5f7203ec1d..ab5996d2be7a 100644
--- a/bundler/lib/bundler/man/bundle-licenses.1
+++ b/bundler/lib/bundler/man/bundle-licenses.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-LICENSES" "1" "April 2026" ""
+.TH "BUNDLE\-LICENSES" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-licenses\fR \- Print the license of all gems in the bundle
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-list.1 b/bundler/lib/bundler/man/bundle-list.1
index 69276822d2cd..e759e0d4493b 100644
--- a/bundler/lib/bundler/man/bundle-list.1
+++ b/bundler/lib/bundler/man/bundle-list.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-LIST" "1" "April 2026" ""
+.TH "BUNDLE\-LIST" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-list\fR \- List all the gems in the bundle
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-lock.1 b/bundler/lib/bundler/man/bundle-lock.1
index ba1915af2e15..396c8ff6ca97 100644
--- a/bundler/lib/bundler/man/bundle-lock.1
+++ b/bundler/lib/bundler/man/bundle-lock.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-LOCK" "1" "April 2026" ""
+.TH "BUNDLE\-LOCK" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-lock\fR \- Creates / Updates a lockfile without installing
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-open.1 b/bundler/lib/bundler/man/bundle-open.1
index 99166e8580f4..2aab59f14b9b 100644
--- a/bundler/lib/bundler/man/bundle-open.1
+++ b/bundler/lib/bundler/man/bundle-open.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-OPEN" "1" "April 2026" ""
+.TH "BUNDLE\-OPEN" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-open\fR \- Opens the source directory for a gem in your bundle
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-outdated.1 b/bundler/lib/bundler/man/bundle-outdated.1
index 87725b9029e3..b739234d8daf 100644
--- a/bundler/lib/bundler/man/bundle-outdated.1
+++ b/bundler/lib/bundler/man/bundle-outdated.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-OUTDATED" "1" "April 2026" ""
+.TH "BUNDLE\-OUTDATED" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-outdated\fR \- List installed gems with newer versions available
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-platform.1 b/bundler/lib/bundler/man/bundle-platform.1
index 486e2d4406bf..39b711126353 100644
--- a/bundler/lib/bundler/man/bundle-platform.1
+++ b/bundler/lib/bundler/man/bundle-platform.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-PLATFORM" "1" "April 2026" ""
+.TH "BUNDLE\-PLATFORM" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-platform\fR \- Displays platform compatibility information
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-plugin.1 b/bundler/lib/bundler/man/bundle-plugin.1
index 1c3feead7630..d182c7789ba1 100644
--- a/bundler/lib/bundler/man/bundle-plugin.1
+++ b/bundler/lib/bundler/man/bundle-plugin.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-PLUGIN" "1" "April 2026" ""
+.TH "BUNDLE\-PLUGIN" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-plugin\fR \- Manage Bundler plugins
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-pristine.1 b/bundler/lib/bundler/man/bundle-pristine.1
index cbfc51399a70..f6cc06657161 100644
--- a/bundler/lib/bundler/man/bundle-pristine.1
+++ b/bundler/lib/bundler/man/bundle-pristine.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-PRISTINE" "1" "April 2026" ""
+.TH "BUNDLE\-PRISTINE" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-pristine\fR \- Restores installed gems to their pristine condition
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-remove.1 b/bundler/lib/bundler/man/bundle-remove.1
index f8981f9fcfcb..2ca40e74db4f 100644
--- a/bundler/lib/bundler/man/bundle-remove.1
+++ b/bundler/lib/bundler/man/bundle-remove.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-REMOVE" "1" "April 2026" ""
+.TH "BUNDLE\-REMOVE" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-remove\fR \- Removes gems from the Gemfile
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-show.1 b/bundler/lib/bundler/man/bundle-show.1
index aaf146fa271b..a2142694b8d3 100644
--- a/bundler/lib/bundler/man/bundle-show.1
+++ b/bundler/lib/bundler/man/bundle-show.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-SHOW" "1" "April 2026" ""
+.TH "BUNDLE\-SHOW" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-show\fR \- Shows all the gems in your bundle, or the path to a gem
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-update.1 b/bundler/lib/bundler/man/bundle-update.1
index e5f18f2a1e26..6a749644e31a 100644
--- a/bundler/lib/bundler/man/bundle-update.1
+++ b/bundler/lib/bundler/man/bundle-update.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-UPDATE" "1" "April 2026" ""
+.TH "BUNDLE\-UPDATE" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-update\fR \- Update your gems to the latest available versions
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle-version.1 b/bundler/lib/bundler/man/bundle-version.1
index 24b5dcef45d7..751a408312a9 100644
--- a/bundler/lib/bundler/man/bundle-version.1
+++ b/bundler/lib/bundler/man/bundle-version.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE\-VERSION" "1" "April 2026" ""
+.TH "BUNDLE\-VERSION" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\-version\fR \- Prints Bundler version information
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/bundle.1 b/bundler/lib/bundler/man/bundle.1
index 492de63295a1..167815631a2b 100644
--- a/bundler/lib/bundler/man/bundle.1
+++ b/bundler/lib/bundler/man/bundle.1
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "BUNDLE" "1" "April 2026" ""
+.TH "BUNDLE" "1" "May 2026" ""
 .SH "NAME"
 \fBbundle\fR \- Ruby Dependency Management
 .SH "SYNOPSIS"
diff --git a/bundler/lib/bundler/man/gemfile.5 b/bundler/lib/bundler/man/gemfile.5
index db04250b8b8c..0874bb5a4a7b 100644
--- a/bundler/lib/bundler/man/gemfile.5
+++ b/bundler/lib/bundler/man/gemfile.5
@@ -1,6 +1,6 @@
 .\" generated with Ronn-NG/v0.10.1
 .\" http://github.com/apjanke/ronn-ng/tree/0.10.1
-.TH "GEMFILE" "5" "April 2026" ""
+.TH "GEMFILE" "5" "May 2026" ""
 .SH "NAME"
 \fBGemfile\fR \- A format for describing gem dependencies for Ruby programs
 .SH "SYNOPSIS"
@@ -460,6 +460,42 @@ The \fBgemspec\fR method adds any runtime dependencies as gem requirements in th
 The \fBgemspec\fR method supports optional \fB:path\fR, \fB:glob\fR, \fB:name\fR, and \fB:development_group\fR options, which control where bundler looks for the \fB\.gemspec\fR, the glob it uses to look for the gemspec (defaults to: \fB{,*,*/*}\.gemspec\fR), what named \fB\.gemspec\fR it uses (if more than one is present), and which group development dependencies are included in\.
 .P
 When a \fBgemspec\fR dependency encounters version conflicts during resolution, the local version under development will always be selected \-\- even if there are remote versions that better match other requirements for the \fBgemspec\fR gem\.
+.SH "OVERRIDE"
+The \fBoverride\fR directive rewrites the version requirement on another gem before resolution runs\. It targets the common case where an upstream gem's published metadata is too narrow on the current project's machine \-\- a stale upper bound, an unwanted floor, or a transitive pin that has to be lifted\.
+.IP "" 4
+.nf
+override <target>, <field>: <operation>
+.fi
+.IP "" 0
+.P
+\fB<target>\fR is a gem name string\. \fB<field>\fR is \fBversion:\fR\. \fB<operation>\fR is one of:
+.IP "\(bu" 4
+a version requirement string (e\.g\. \fB">= 8\.0"\fR), which \fBreplaces\fR the target's version requirement absolutely\. The original requirement, both direct and transitive, is discarded in favour of the override\.
+.IP "\(bu" 4
+\fB:ignore_upper\fR, which removes upper\-bound operators (\fB<\fR and \fB<=\fR) from the existing requirement and folds \fB~>\fR into its lower bound (\fB~> 1\.5\fR becomes \fB>= 1\.5\fR)\. Other operators, including \fB!=\fR, are preserved\.
+.IP "\(bu" 4
+\fBnil\fR, which collapses the requirement to \fB>= 0\fR (no constraint at all)\.
+.IP "" 0
+.P
+Multiple \fBoverride\fR calls for distinct targets are allowed; declaring the same \fBtarget\fR and \fBfield\fR twice is an error\.
+.IP "" 4
+.nf
+source "https://rubygems\.org"
+
+# Force every reference to "rails" \-\- direct or transitive \-\- to >= 8\.0\.
+override "rails", version: ">= 8\.0"
+
+# Strip the upper bound on nokogiri\.
+override "nokogiri", version: :ignore_upper
+
+# Drop the version pin on legacy entirely\.
+override "legacy", version: nil
+
+gem "rails", "~> 7\.0"
+.fi
+.IP "" 0
+.P
+The override only affects resolution; \fBGemfile\.lock\fR continues to reflect the resolved versions, not the rewritten requirements\.
 .SH "SOURCE PRIORITY"
 When attempting to locate a gem to satisfy a gem requirement, bundler uses the following priority order:
 .IP "1." 4
diff --git a/bundler/lib/bundler/man/gemfile.5.ronn b/bundler/lib/bundler/man/gemfile.5.ronn
index 18d7bb826e44..1779fc0a0152 100644
--- a/bundler/lib/bundler/man/gemfile.5.ronn
+++ b/bundler/lib/bundler/man/gemfile.5.ronn
@@ -541,6 +541,45 @@ When a `gemspec` dependency encounters version conflicts during resolution, the
 local version under development will always be selected -- even if there are
 remote versions that better match other requirements for the `gemspec` gem.
 
+## OVERRIDE
+
+The `override` directive rewrites the version requirement on another gem
+before resolution runs. It targets the common case where an upstream gem's
+published metadata is too narrow on the current project's machine -- a stale
+upper bound, an unwanted floor, or a transitive pin that has to be lifted.
+
+    override <target>, <field>: <operation>
+
+`<target>` is a gem name string. `<field>` is `version:`. `<operation>` is
+one of:
+
+  * a version requirement string (e.g. `">= 8.0"`), which **replaces** the
+    target's version requirement absolutely. The original requirement, both
+    direct and transitive, is discarded in favour of the override.
+  * `:ignore_upper`, which removes upper-bound operators (`<` and `<=`) from
+    the existing requirement and folds `~>` into its lower bound (`~> 1.5`
+    becomes `>= 1.5`). Other operators, including `!=`, are preserved.
+  * `nil`, which collapses the requirement to `>= 0` (no constraint at all).
+
+Multiple `override` calls for distinct targets are allowed; declaring the
+same `target` and `field` twice is an error.
+
+    source "https://rubygems.org"
+
+    # Force every reference to "rails" -- direct or transitive -- to >= 8.0.
+    override "rails", version: ">= 8.0"
+
+    # Strip the upper bound on nokogiri.
+    override "nokogiri", version: :ignore_upper
+
+    # Drop the version pin on legacy entirely.
+    override "legacy", version: nil
+
+    gem "rails", "~> 7.0"
+
+The override only affects resolution; `Gemfile.lock` continues to reflect
+the resolved versions, not the rewritten requirements.
+
 ## SOURCE PRIORITY
 
 When attempting to locate a gem to satisfy a gem requirement,
diff --git a/bundler/lib/bundler/override.rb b/bundler/lib/bundler/override.rb
new file mode 100644
index 000000000000..1ca6d2fde5d4
--- /dev/null
+++ b/bundler/lib/bundler/override.rb
@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+module Bundler
+  class Override
+    UPPER_BOUND_OPERATORS = ["<", "<="].freeze
+
+    attr_reader :target, :field, :operation
+
+    def initialize(target, field, operation)
+      @target = target
+      @field = field
+      @operation = operation
+    end
+
+    def apply_to(requirement)
+      case operation
+      when nil
+        Gem::Requirement.default
+      when :ignore_upper
+        remove_upper_bounds(requirement)
+      when String
+        Gem::Requirement.new(operation)
+      else
+        raise ArgumentError, "unsupported override operation: #{operation.inspect}"
+      end
+    end
+
+    private
+
+    def remove_upper_bounds(requirement)
+      return Gem::Requirement.default if requirement.nil? || requirement.none?
+
+      preserved = requirement.requirements.filter_map do |op, version|
+        if UPPER_BOUND_OPERATORS.include?(op)
+          nil
+        elsif op == "~>"
+          [">=", version]
+        else
+          [op, version]
+        end
+      end
+
+      return Gem::Requirement.default if preserved.empty?
+
+      Gem::Requirement.new(preserved.map {|op, v| "#{op} #{v}" })
+    end
+  end
+end
diff --git a/bundler/lib/bundler/resolver.rb b/bundler/lib/bundler/resolver.rb
index 3c361d8ea51a..5e934e2a12e6 100644
--- a/bundler/lib/bundler/resolver.rb
+++ b/bundler/lib/bundler/resolver.rb
@@ -510,7 +510,7 @@ def requirement_to_range(requirement)
     end
 
     def to_dependency_hash(dependencies, packages)
-      dependencies.inject({}) do |deps, dep|
+      apply_overrides(dependencies).inject({}) do |deps, dep|
         package = packages[dep.name]
 
         current_req = deps[package]
@@ -526,6 +526,16 @@ def to_dependency_hash(dependencies, packages)
       end
     end
 
+    def apply_overrides(dependencies)
+      return dependencies if @base.overrides.empty?
+
+      dependencies.map do |dep|
+        override = @base.overrides.find {|o| o.target == dep.name && o.field == :version }
+        next dep unless override
+        Gem::Dependency.new(dep.name, override.apply_to(dep.requirement))
+      end
+    end
+
     def bundler_not_found_message(conflict_dependencies)
       candidate_specs = filter_matching_specs(default_bundler_source.specs.search("bundler"), conflict_dependencies)
 
diff --git a/bundler/lib/bundler/resolver/base.rb b/bundler/lib/bundler/resolver/base.rb
index 932a92ff4156..00bdd08303df 100644
--- a/bundler/lib/bundler/resolver/base.rb
+++ b/bundler/lib/bundler/resolver/base.rb
@@ -5,9 +5,10 @@
 module Bundler
   class Resolver
     class Base
-      attr_reader :packages, :requirements, :source_requirements, :locked_specs
+      attr_reader :packages, :requirements, :source_requirements, :locked_specs, :overrides
 
       def initialize(source_requirements, dependencies, base, platforms, options)
+        @overrides = options.delete(:overrides) || []
         @source_requirements = source_requirements
         @locked_specs = options[:locked_specs]
 
diff --git a/spec/bundler/definition_spec.rb b/spec/bundler/definition_spec.rb
index 8c7d5667ac66..8c4a5a0331e2 100644
--- a/spec/bundler/definition_spec.rb
+++ b/spec/bundler/definition_spec.rb
@@ -3,6 +3,24 @@
 require "bundler/definition"
 
 RSpec.describe Bundler::Definition do
+  describe "#overrides" do
+    before do
+      allow(Bundler::SharedHelpers).to receive(:find_gemfile) { bundled_app_gemfile }
+    end
+
+    subject { Bundler::Definition.new(bundled_app_lock, [], Bundler::SourceList.new, {}) }
+
+    it "defaults to an empty array" do
+      expect(subject.overrides).to eq([])
+    end
+
+    it "is writable" do
+      override = Bundler::Override.new("rails", :version, ">= 8.0")
+      subject.overrides = [override]
+      expect(subject.overrides).to eq([override])
+    end
+  end
+
   describe "#lock" do
     before do
       allow(Bundler::SharedHelpers).to receive(:find_gemfile) { bundled_app_gemfile }
diff --git a/spec/bundler/dsl_spec.rb b/spec/bundler/dsl_spec.rb
index 6ba2e728b573..39f745c05efe 100644
--- a/spec/bundler/dsl_spec.rb
+++ b/spec/bundler/dsl_spec.rb
@@ -366,4 +366,108 @@
       end
     end
   end
+
+  describe "#override" do
+    it "stores an Override for a gem with a version: operation" do
+      subject.override("rails", version: ">= 8.0")
+
+      expect(subject.overrides.size).to eq(1)
+      override = subject.overrides.first
+      expect(override.target).to eq("rails")
+      expect(override.field).to eq(:version)
+      expect(override.operation).to eq(">= 8.0")
+    end
+
+    it "accepts :ignore_upper as the operation" do
+      subject.override("nokogiri", version: :ignore_upper)
+      expect(subject.overrides.first.operation).to eq(:ignore_upper)
+    end
+
+    it "accepts nil as the operation" do
+      subject.override("legacy", version: nil)
+      expect(subject.overrides.first.operation).to be_nil
+    end
+
+    it "appends to overrides across multiple statements" do
+      subject.override("rails", version: ">= 8.0")
+      subject.override("nokogiri", version: :ignore_upper)
+      expect(subject.overrides.map(&:target)).to eq(["rails", "nokogiri"])
+    end
+
+    it "is empty by default" do
+      expect(subject.overrides).to eq([])
+    end
+
+    it "raises ArgumentError when target is :all and version: is given" do
+      expect do
+        subject.override(:all, version: ">= 8.0")
+      end.to raise_error(ArgumentError, /`override :all, version:` is not allowed/)
+    end
+
+    it "rejects :all + version: even when other fields are also given" do
+      expect do
+        subject.override(:all, required_ruby_version: :ignore_upper, version: ">= 8.0")
+      end.to raise_error(ArgumentError, /`override :all, version:` is not allowed/)
+    end
+
+    it "does not record any override when :all + version: is rejected" do
+      expect do
+        subject.override(:all, version: ">= 8.0")
+      end.to raise_error(ArgumentError)
+      expect(subject.overrides).to eq([])
+    end
+
+    it "raises ArgumentError when target is neither :all nor a string" do
+      expect do
+        subject.override(:rails, version: ">= 8.0")
+      end.to raise_error(ArgumentError, /target must be :all or a gem name string/)
+    end
+
+    it "raises ArgumentError for an unsupported field" do
+      expect do
+        subject.override("rails", required_ruby_version: :ignore_upper)
+      end.to raise_error(ArgumentError, /unsupported override field `required_ruby_version:`/)
+    end
+
+    it "raises ArgumentError for a non-string, non-symbol, non-nil operation" do
+      expect do
+        subject.override("rails", version: 42)
+      end.to raise_error(ArgumentError, /override operation must be a String, Symbol, or nil/)
+    end
+
+    it "raises ArgumentError for an unsupported symbol operation" do
+      expect do
+        subject.override("rails", version: :explode)
+      end.to raise_error(ArgumentError, /unsupported override operation/)
+    end
+
+    it "rejects atomically when one field in a multi-field call is invalid" do
+      expect do
+        subject.override("rails", version: ">= 8.0", required_ruby_version: :ignore_upper)
+      end.to raise_error(ArgumentError, /unsupported override field/)
+      expect(subject.overrides).to eq([])
+    end
+
+    it "raises ArgumentError when the same target and field are overridden twice" do
+      subject.override("rails", version: ">= 8.0")
+      expect do
+        subject.override("rails", version: :ignore_upper)
+      end.to raise_error(ArgumentError, /duplicate override for "rails" `version:`/)
+    end
+
+    it "keeps the original override when a duplicate is rejected" do
+      subject.override("rails", version: ">= 8.0")
+      expect do
+        subject.override("rails", version: :ignore_upper)
+      end.to raise_error(ArgumentError)
+      expect(subject.overrides.size).to eq(1)
+      expect(subject.overrides.first.operation).to eq(">= 8.0")
+    end
+
+    it "allows different targets with the same field" do
+      subject.override("rails", version: ">= 8.0")
+      subject.override("nokogiri", version: :ignore_upper)
+      expect(subject.overrides.size).to eq(2)
+    end
+  end
 end
diff --git a/spec/bundler/override_spec.rb b/spec/bundler/override_spec.rb
new file mode 100644
index 000000000000..da3b5aad87a0
--- /dev/null
+++ b/spec/bundler/override_spec.rb
@@ -0,0 +1,76 @@
+# frozen_string_literal: true
+
+RSpec.describe Bundler::Override do
+  describe "#apply_to" do
+    context "when operation is a version spec string" do
+      it "replaces the existing requirement entirely" do
+        override = described_class.new("rails", :version, ">= 8.0")
+        result = override.apply_to(Gem::Requirement.new(">= 1.0", "< 2.0"))
+        expect(result).to eq(Gem::Requirement.new(">= 8.0"))
+      end
+
+      it "ignores the existing requirement regardless of its content" do
+        override = described_class.new("rails", :version, "= 1.0")
+        result = override.apply_to(Gem::Requirement.new(">= 99.0"))
+        expect(result).to eq(Gem::Requirement.new("= 1.0"))
+      end
+    end
+
+    context "when operation is :ignore_upper" do
+      it "removes < and <= operators" do
+        override = described_class.new("rails", :version, :ignore_upper)
+        result = override.apply_to(Gem::Requirement.new(">= 1.0", "< 2.0"))
+        expect(result).to eq(Gem::Requirement.new(">= 1.0"))
+      end
+
+      it "keeps >, >=, = operators" do
+        override = described_class.new("rails", :version, :ignore_upper)
+        result = override.apply_to(Gem::Requirement.new("> 1.0", "<= 2.0"))
+        expect(result).to eq(Gem::Requirement.new("> 1.0"))
+      end
+
+      it "converts ~> to >= preserving the lower bound" do
+        override = described_class.new("rails", :version, :ignore_upper)
+        result = override.apply_to(Gem::Requirement.new("~> 1.5"))
+        expect(result).to eq(Gem::Requirement.new(">= 1.5"))
+      end
+
+      it "preserves != exclusion constraints" do
+        override = described_class.new("rails", :version, :ignore_upper)
+        result = override.apply_to(Gem::Requirement.new(">= 1.0", "!= 1.5.0", "< 2.0"))
+        expect(result).to eq(Gem::Requirement.new(">= 1.0", "!= 1.5.0"))
+      end
+
+      it "returns the default requirement when only upper bounds remain" do
+        override = described_class.new("rails", :version, :ignore_upper)
+        result = override.apply_to(Gem::Requirement.new("< 2.0"))
+        expect(result).to eq(Gem::Requirement.default)
+      end
+
+      it "returns the default requirement when the input is nil" do
+        override = described_class.new("rails", :version, :ignore_upper)
+        expect(override.apply_to(nil)).to eq(Gem::Requirement.default)
+      end
+
+      it "returns the default requirement when the input is already the default" do
+        override = described_class.new("rails", :version, :ignore_upper)
+        expect(override.apply_to(Gem::Requirement.default)).to eq(Gem::Requirement.default)
+      end
+    end
+
+    context "when operation is nil" do
+      it "returns the default requirement" do
+        override = described_class.new("rails", :version, nil)
+        result = override.apply_to(Gem::Requirement.new(">= 1.0", "< 2.0"))
+        expect(result).to eq(Gem::Requirement.default)
+      end
+    end
+
+    context "when operation is unsupported" do
+      it "raises ArgumentError" do
+        override = described_class.new("rails", :version, 42)
+        expect { override.apply_to(Gem::Requirement.default) }.to raise_error(ArgumentError, /unsupported override operation/)
+      end
+    end
+  end
+end
diff --git a/spec/install/gemfile/override_spec.rb b/spec/install/gemfile/override_spec.rb
new file mode 100644
index 000000000000..7a7f8078a817
--- /dev/null
+++ b/spec/install/gemfile/override_spec.rb
@@ -0,0 +1,132 @@
+# frozen_string_literal: true
+
+RSpec.describe "override DSL" do
+  context "with a version: string operation" do
+    it "replaces a direct dependency requirement with the override version spec" do
+      install_gemfile <<-G
+        source "https://gem.repo1"
+        override "myrack", version: "= 0.9.1"
+        gem "myrack"
+      G
+
+      expect(the_bundle).to include_gems "myrack 0.9.1"
+    end
+
+    it "replaces a transitive dependency requirement" do
+      install_gemfile <<-G
+        source "https://gem.repo1"
+        override "myrack", version: "= 1.0.0"
+        gem "myrack_middleware"
+      G
+
+      expect(the_bundle).to include_gems "myrack 1.0.0", "myrack_middleware 1.0"
+    end
+
+    it "replaces the requirement even when the Gemfile pins a different version" do
+      install_gemfile <<-G
+        source "https://gem.repo1"
+        override "myrack", version: "= 0.9.1"
+        gem "myrack", "= 1.0.0"
+      G
+
+      expect(the_bundle).to include_gems "myrack 0.9.1"
+    end
+
+    it "applies the override against an existing lockfile" do
+      install_gemfile <<-G
+        source "https://gem.repo1"
+        gem "myrack"
+      G
+
+      expect(the_bundle).to include_gems "myrack 1.0.0"
+
+      gemfile <<-G
+        source "https://gem.repo1"
+        override "myrack", version: "= 0.9.1"
+        gem "myrack"
+      G
+
+      bundle :install
+
+      expect(the_bundle).to include_gems "myrack 0.9.1"
+    end
+
+    it "pins a prerelease version that the Gemfile dependency would otherwise filter out" do
+      build_repo2 do
+        build_gem "has_prerelease", "1.0"
+        build_gem "has_prerelease", "1.1.pre"
+      end
+
+      install_gemfile <<-G
+        source "https://gem.repo2"
+        override "has_prerelease", version: "= 1.1.pre"
+        gem "has_prerelease"
+      G
+
+      expect(the_bundle).to include_gems "has_prerelease 1.1.pre"
+    end
+  end
+
+  context "with a version: :ignore_upper operation" do
+    it "strips a < upper bound on a direct dependency" do
+      install_gemfile <<-G
+        source "https://gem.repo1"
+        override "myrack", version: :ignore_upper
+        gem "myrack", "< 1.0"
+      G
+
+      expect(the_bundle).to include_gems "myrack 1.0.0"
+    end
+
+    it "folds ~> into >= so newer versions become reachable" do
+      install_gemfile <<-G
+        source "https://gem.repo1"
+        override "myrack", version: :ignore_upper
+        gem "myrack", "~> 0.9.1"
+      G
+
+      expect(the_bundle).to include_gems "myrack 1.0.0"
+    end
+  end
+
+  context "with a version: nil operation" do
+    it "drops a direct dependency's pin entirely" do
+      install_gemfile <<-G
+        source "https://gem.repo1"
+        override "myrack", version: nil
+        gem "myrack", "= 0.9.1"
+      G
+
+      expect(the_bundle).to include_gems "myrack 1.0.0"
+    end
+
+    it "drops a transitive dependency's pin entirely" do
+      install_gemfile <<-G
+        source "https://gem.repo1"
+        override "myrack", version: nil
+        gem "myrack_middleware"
+      G
+
+      expect(the_bundle).to include_gems "myrack 1.0.0", "myrack_middleware 1.0"
+    end
+
+    it "applies a transitive-only override against an existing lockfile" do
+      install_gemfile <<-G
+        source "https://gem.repo1"
+        gem "myrack_middleware"
+      G
+
+      expect(the_bundle).to include_gems "myrack 0.9.1", "myrack_middleware 1.0"
+
+      gemfile <<-G
+        source "https://gem.repo1"
+        override "myrack", version: "= 1.0.0"
+        gem "myrack_middleware"
+      G
+
+      bundle :install
+
+      expect(the_bundle).to include_gems "myrack 1.0.0", "myrack_middleware 1.0"
+    end
+  end
+end
diff --git a/spec/support/windows_tag_group.rb b/spec/support/windows_tag_group.rb
index b91deb7ed3e6..fb9c0811493f 100644
--- a/spec/support/windows_tag_group.rb
+++ b/spec/support/windows_tag_group.rb
@@ -189,6 +189,8 @@ module WindowsTagGroup
         "spec/bundler/uri_normalizer_spec.rb",
         "spec/install/gems/no_build_extension_spec.rb",
         "spec/install/gems/no_install_plugin_spec.rb",
+        "spec/bundler/override_spec.rb",
+        "spec/install/gemfile/override_spec.rb",
       ],
     }.freeze
   end