diff --git a/bridgetown-core/lib/bridgetown-core.rb b/bridgetown-core/lib/bridgetown-core.rb
index 2da038198..2823570f2 100644
--- a/bridgetown-core/lib/bridgetown-core.rb
+++ b/bridgetown-core/lib/bridgetown-core.rb
@@ -73,6 +73,8 @@ def to_liquid
 class Rb < String; end
 
 module Bridgetown
+  using Bridgetown::Refinements
+
   autoload :Cache,               "bridgetown-core/cache"
   autoload :Current,             "bridgetown-core/current"
   autoload :Cleaner,             "bridgetown-core/cleaner"
diff --git a/bridgetown-core/lib/bridgetown-core/collection.rb b/bridgetown-core/lib/bridgetown-core/collection.rb
index 39c8dd002..367f0a16f 100644
--- a/bridgetown-core/lib/bridgetown-core/collection.rb
+++ b/bridgetown-core/lib/bridgetown-core/collection.rb
@@ -2,6 +2,7 @@
 
 module Bridgetown
   class Collection
+    using Bridgetown::Refinements
     include Enumerable
 
     # @return [Bridgetown::Site]
diff --git a/bridgetown-core/lib/bridgetown-core/commands/concerns/actions.rb b/bridgetown-core/lib/bridgetown-core/commands/concerns/actions.rb
index f8ab5c038..886a8d6e7 100644
--- a/bridgetown-core/lib/bridgetown-core/commands/concerns/actions.rb
+++ b/bridgetown-core/lib/bridgetown-core/commands/concerns/actions.rb
@@ -3,6 +3,8 @@
 module Bridgetown
   module Commands
     module Actions
+      using Bridgetown::Refinements
+
       GITHUB_REGEX = %r!https://github\.com!
       GITHUB_TREE_REGEX = %r!#{GITHUB_REGEX}/.*/.*/tree/.*/?!
       GITHUB_BLOB_REGEX = %r!#{GITHUB_REGEX}/.*/.*/blob/!
diff --git a/bridgetown-core/lib/bridgetown-core/commands/console.rb b/bridgetown-core/lib/bridgetown-core/commands/console.rb
index 9b1e43bca..8203b1da3 100644
--- a/bridgetown-core/lib/bridgetown-core/commands/console.rb
+++ b/bridgetown-core/lib/bridgetown-core/commands/console.rb
@@ -103,6 +103,7 @@ def console # rubocop:disable Metrics
         Bridgetown.logger.info "",
                                "You can also access #{"collections".cyan} or perform a " \
                                "#{"reload!".cyan}"
+        Bridgetown.logger.info "", "For extra Ruby smarts: #{"using Bridgetown::Refinements".cyan}"
 
         trap("SIGINT") do
           irb.signal_handle
diff --git a/bridgetown-core/lib/bridgetown-core/component.rb b/bridgetown-core/lib/bridgetown-core/component.rb
index 1120db878..16c1b584c 100644
--- a/bridgetown-core/lib/bridgetown-core/component.rb
+++ b/bridgetown-core/lib/bridgetown-core/component.rb
@@ -2,6 +2,7 @@
 
 module Bridgetown
   class Component
+    using Bridgetown::Refinements
     include Bridgetown::Streamlined
     extend Forwardable
 
@@ -120,7 +121,7 @@ def slot(name, input = nil, replace: false, &block)
       content = block.nil? ? input.to_s : view_context.capture(&block)
 
       name = name.to_s
-      slots.reject! { _1.name == name } if replace
+      slots.reject!(&:name.(:==, name)) if replace
 
       slots << Slot.new(name:, content:, context: self, transform: false)
 
diff --git a/bridgetown-core/lib/bridgetown-core/concerns/site/fast_refreshable.rb b/bridgetown-core/lib/bridgetown-core/concerns/site/fast_refreshable.rb
index b7827cb26..84df0404b 100644
--- a/bridgetown-core/lib/bridgetown-core/concerns/site/fast_refreshable.rb
+++ b/bridgetown-core/lib/bridgetown-core/concerns/site/fast_refreshable.rb
@@ -2,6 +2,8 @@
 
 class Bridgetown::Site
   module FastRefreshable
+    using Bridgetown::Refinements
+
     def fast_refresh(paths = [], reload_if_needed: false) # rubocop:todo Metrics
       FileUtils.rm_f(Bridgetown.build_errors_path)
 
@@ -132,7 +134,7 @@ def mark_original_page_resources_for_fast_refresh(pages)
     end
 
     def transform_resources_for_fast_refresh(marked_resources, found_gen_pages)
-      marked_resources.each { _1.transform!.write }
+      marked_resources.each(&:transform!.(:write))
       number_of_resources = marked_resources.length
       number_of_resources += 1 if found_gen_pages
       Bridgetown.logger.info(
diff --git a/bridgetown-core/lib/bridgetown-core/drops/relations_drop.rb b/bridgetown-core/lib/bridgetown-core/drops/relations_drop.rb
index 7c8302cb3..de0399e5a 100644
--- a/bridgetown-core/lib/bridgetown-core/drops/relations_drop.rb
+++ b/bridgetown-core/lib/bridgetown-core/drops/relations_drop.rb
@@ -3,6 +3,7 @@
 module Bridgetown
   module Drops
     class RelationsDrop < Drop
+      using Bridgetown::Refinements
       mutable false
 
       def [](type)
diff --git a/bridgetown-core/lib/bridgetown-core/helpers.rb b/bridgetown-core/lib/bridgetown-core/helpers.rb
index 4d9be29e2..963b1f2dd 100644
--- a/bridgetown-core/lib/bridgetown-core/helpers.rb
+++ b/bridgetown-core/lib/bridgetown-core/helpers.rb
@@ -6,6 +6,7 @@
 module Bridgetown
   class RubyTemplateView
     class Helpers
+      using Bridgetown::Refinements
       include Bridgetown::Filters
       include Bridgetown::Filters::FromLiquid
       include ::Streamlined::Helpers
@@ -208,7 +209,7 @@ def slot(name, input = nil, replace: false, transform: true, &block)
                    end
 
         name = name.to_s
-        resource.slots.reject! { _1.name == name } if replace
+        resource.slots.reject!(&:name.(:==, name)) if replace
         resource.slots << Slot.new(
           name:,
           content:,
diff --git a/bridgetown-core/lib/bridgetown-core/model/repo_origin.rb b/bridgetown-core/lib/bridgetown-core/model/repo_origin.rb
index a456cce22..5a5c0d1f7 100644
--- a/bridgetown-core/lib/bridgetown-core/model/repo_origin.rb
+++ b/bridgetown-core/lib/bridgetown-core/model/repo_origin.rb
@@ -3,6 +3,7 @@
 module Bridgetown
   module Model
     class RepoOrigin < Origin
+      using Bridgetown::Refinements
       include Bridgetown::FrontMatter::Importer
 
       # @return [String]
diff --git a/bridgetown-core/lib/bridgetown-core/resource/relations.rb b/bridgetown-core/lib/bridgetown-core/resource/relations.rb
index fd2eb44c8..6d65c2b92 100644
--- a/bridgetown-core/lib/bridgetown-core/resource/relations.rb
+++ b/bridgetown-core/lib/bridgetown-core/resource/relations.rb
@@ -3,6 +3,8 @@
 module Bridgetown
   module Resource
     class Relations
+      using Bridgetown::Refinements
+
       # @return [Bridgetown::Resource::Base]
       attr_reader :resource
 
diff --git a/bridgetown-core/lib/bridgetown-core/ruby_template_view.rb b/bridgetown-core/lib/bridgetown-core/ruby_template_view.rb
index e5693ce48..260873f2b 100644
--- a/bridgetown-core/lib/bridgetown-core/ruby_template_view.rb
+++ b/bridgetown-core/lib/bridgetown-core/ruby_template_view.rb
@@ -22,6 +22,7 @@ def helper(name, &helper_block)
   class RubyTemplateView
     require "bridgetown-core/helpers"
 
+    using Bridgetown::Refinements
     include Bridgetown::Streamlined
 
     attr_reader :layout, :resource, :paginator, :site, :content
@@ -129,7 +130,7 @@ def _liquid_context
     end
 
     def _partial_path(partial_name, ext)
-      partial_name = partial_name.split("/").tap { _1.last.prepend("_") }.join("/")
+      partial_name = partial_name.split("/").tap(&:last.(:prepend, "_")).join("/")
 
       # TODO: see if there's a workaround for this to speed up performance
       site.in_source_dir(site.config[:partials_dir], "#{partial_name}.#{ext}")
diff --git a/bridgetown-core/lib/bridgetown-core/slot.rb b/bridgetown-core/lib/bridgetown-core/slot.rb
index 53895d9dd..5d12585a5 100644
--- a/bridgetown-core/lib/bridgetown-core/slot.rb
+++ b/bridgetown-core/lib/bridgetown-core/slot.rb
@@ -2,6 +2,8 @@
 
 module Bridgetown
   class Slot
+    using Bridgetown::Refinements
+
     include Transformable
 
     # @return [String]
@@ -33,7 +35,7 @@ def converters
                               context.transformer.send(:converters) :
                               context.send(:converters)
 
-      document_converters.select { _1.class.supports_slots? }
+      document_converters.select(&:class.(:supports_slots?))
     end
   end
 end
diff --git a/bridgetown-foundation/benchmark/refinements.rb b/bridgetown-foundation/benchmark/refinements.rb
new file mode 100644
index 000000000..4de3e2260
--- /dev/null
+++ b/bridgetown-foundation/benchmark/refinements.rb
@@ -0,0 +1,50 @@
+# frozen_string_literal: true
+
+require "benchmark"
+
+class TestInclusion
+  module StringAdder
+    def included_add(num)
+      to_i + num
+    end
+  end
+
+  String.include StringAdder
+
+  def self.perform
+    raise "crash!" unless "10".included_add(20) == 30
+  end
+end
+
+module StringAdderRefinement
+  refine String do
+    def refined_add(num)
+      to_i + num
+    end
+  end
+end
+
+class TestRefinement
+  using StringAdderRefinement
+
+  def self.perform
+    raise "crash!" unless "10".refined_add(20) == 30
+  end
+end
+
+raise "Unconfirmed!" unless "".respond_to?(:included_add)
+raise "Unconfirmed!" if "".respond_to?(:refined_add)
+
+n = 1_000_000
+Benchmark.bmbm(12) do |x|
+  x.report("inclusion:") do
+    n.times do
+      TestInclusion.perform
+    end
+  end
+  x.report("refinements:") do
+    n.times do
+      TestRefinement.perform
+    end
+  end
+end
diff --git a/bridgetown-foundation/lib/bridgetown-foundation.rb b/bridgetown-foundation/lib/bridgetown-foundation.rb
index 6110f15d0..f84499b41 100644
--- a/bridgetown-foundation/lib/bridgetown-foundation.rb
+++ b/bridgetown-foundation/lib/bridgetown-foundation.rb
@@ -3,39 +3,33 @@
 require "bridgetown/foundation/version"
 require "zeitwerk"
 
-class Module
-  # Due to Active Support incompatibility, we can't extend Gem::Deprecate directly in `Object`
-  # So we're pulling this in as `gem_deprecate` from `deprecate`:
-  # https://github.com/rubygems/rubygems/blob/v3.5.9/lib/rubygems/deprecate.rb
-  #
-  # Pass in the deprecated method name, the new method name, and the year & month it'll be removed
+module Bridgetown::Foundation
+  # This is loosly based on the `deprecate` method in `Gem::Deprecate`
   #
+  # @param target [Object]
   # @param name [Symbol] e.g. `:howdy`
   # @param repl [Symbol] e.g. `:hello`
   # @param year [Integer] e.g. `2025`
   # @param month [Integer] e.g. `1` for January
-  def gem_deprecate(name, repl, year, month)
-    # rubocop:disable Style/FormatStringToken
-    class_eval do
-      old = "_deprecated_#{name}"
-      alias_method old, name
-      define_method name do |*args, &block|
-        klass = is_a? Module
-        target = klass ? "#{self}." : "#{self.class}#"
-        msg = [
-          "NOTE: #{target}#{name} is deprecated",
-          repl == :none ? " with no replacement" : "; use #{repl} instead",
-          format(". It will be removed on or after %4d-%02d.", year, month),
-          "\n#{target}#{name} called from #{Gem.location_of_caller.join(":")}",
-        ]
-        warn "#{msg.join}." unless Gem::Deprecate.skip
-        send old, *args, &block
-      end
-    end
-    # rubocop:enable Style/FormatStringToken
+  def self.deprecation_warning(target, name, repl, year, month) # rubocop:disable Metrics/ParameterLists
+    klass = target.is_a?(Module)
+    target = klass ? "#{self}." : "#{self.class}#"
+    msg = [
+      "NOTE: #{target}#{name} is deprecated",
+      repl == :none ? " with no replacement" : "; use #{repl} instead",
+      format(". It will be removed on or after %4d-%02d.", year, month), # rubocop:disable Style/FormatStringToken
+      "\n#{target}#{name} called from #{Gem.location_of_caller.join(":")}",
+    ]
+    warn "#{msg.join}."
   end
 end
 
+# You can add `using Bridgetown::Refinements` to any portion of your Ruby code to load in all
+# of the refinements available in Foundation. Or you can add a using statement for a particular
+# refinement which lives inside `Bridgetown::Foundation::RefineExt`.
+module Bridgetown::Refinements
+end
+
 Zeitwerk.with_loader do |l|
   l.push_dir "#{__dir__}/bridgetown/foundation", namespace: Bridgetown::Foundation
   l.ignore "#{__dir__}/bridgetown/foundation/version.rb"
diff --git a/bridgetown-foundation/lib/bridgetown/foundation/core_ext/string.rb b/bridgetown-foundation/lib/bridgetown/foundation/core_ext/string.rb
index 71e6a53e8..74f31ce58 100644
--- a/bridgetown-foundation/lib/bridgetown/foundation/core_ext/string.rb
+++ b/bridgetown-foundation/lib/bridgetown/foundation/core_ext/string.rb
@@ -3,30 +3,6 @@
 module Bridgetown::Foundation
   module CoreExt
     module String
-      module Indentation
-        def indent!(indent_by, *args)
-          if args.length.positive?
-            Kernel.warn "multiple arguments aren't supported by `indent!' in Bridgetown", uplevel: 1
-          end
-
-          gsub! %r!^(?\!$)!, " " * indent_by
-        end
-
-        def indent(indent_by, *args)
-          if args.length.positive?
-            Kernel.warn "multiple arguments aren't supported by `indent' in Bridgetown", uplevel: 1
-          end
-
-          dup.indent!(indent_by)
-        end
-      end
-
-      module Questionable
-        def questionable = Bridgetown::Foundation::QuestionableString.new(self)
-        alias_method :inquiry, :questionable
-        gem_deprecate :inquiry, :questionable, 2024, 12
-      end
-
       module StartsWithAndEndsWith
         def self.included(klass)
           klass.alias_method :starts_with?, :start_with?
@@ -34,7 +10,7 @@ def self.included(klass)
         end
       end
 
-      ::String.include Indentation, Questionable, StartsWithAndEndsWith
+      ::String.include StartsWithAndEndsWith
     end
   end
 end
diff --git a/bridgetown-foundation/lib/bridgetown/foundation/core_ext/module.rb b/bridgetown-foundation/lib/bridgetown/foundation/refine_ext/module.rb
similarity index 68%
rename from bridgetown-foundation/lib/bridgetown/foundation/core_ext/module.rb
rename to bridgetown-foundation/lib/bridgetown/foundation/refine_ext/module.rb
index 76f025b8b..d432b2401 100644
--- a/bridgetown-foundation/lib/bridgetown/foundation/core_ext/module.rb
+++ b/bridgetown-foundation/lib/bridgetown/foundation/refine_ext/module.rb
@@ -1,11 +1,15 @@
 # frozen_string_literal: true
 
 module Bridgetown::Foundation
-  module CoreExt
+  module RefineExt
     module Module
-      module Nested
+      using RefineExt::Object
+
+      refine ::Module do
         def nested_within?(other)
-          other.nested_parents.within?(nested_parents[1..])
+          return false if self == other
+
+          other.nested_parents.within?(nested_parents) #[1..])
         end
 
         def nested_parents
@@ -25,8 +29,12 @@ def nested_name
           name&.split("::")&.last
         end
       end
-
-      ::Module.include Nested
     end
   end
 end
+
+module Bridgetown
+  module Refinements
+    include Foundation::RefineExt::Module
+  end
+end
diff --git a/bridgetown-foundation/lib/bridgetown/foundation/core_ext/object.rb b/bridgetown-foundation/lib/bridgetown/foundation/refine_ext/object.rb
similarity index 87%
rename from bridgetown-foundation/lib/bridgetown/foundation/core_ext/object.rb
rename to bridgetown-foundation/lib/bridgetown/foundation/refine_ext/object.rb
index d1c0bf448..ac54c889f 100644
--- a/bridgetown-foundation/lib/bridgetown/foundation/core_ext/object.rb
+++ b/bridgetown-foundation/lib/bridgetown/foundation/refine_ext/object.rb
@@ -1,9 +1,9 @@
 # frozen_string_literal: true
 
 module Bridgetown::Foundation
-  module CoreExt
+  module RefineExt
     module Object
-      module WithinOther
+      refine ::Object do
         # This method lets you check if the receiver is "within" the other object. In most cases,
         # this check is accomplished via the `include?` method…aka, `10.within? [5, 10]` would
         # return `true` as `[5, 10].include? 10` is true. And String/String comparison are
@@ -32,6 +32,8 @@ def within?(other) # rubocop:disable Metrics
           end
 
           if is_a?(Array) && other.is_a?(Array)
+            return false if empty?
+
             return difference(other).empty?
           end
 
@@ -51,11 +53,16 @@ def within?(other) # rubocop:disable Metrics
 
         # NOTE: if you _really_ need to preserve Active Support's `in?` functionality, you can just
         #   require "active_support/core_ext/object/inclusion"
-        alias_method :in?, :within?
-        gem_deprecate :in?, :within?, 2024, 12
+        def in?(...) = Bridgetown::Foundation.deprecation_warning(
+          self, :in?, :within?, 2024, 12
+        ).then { within?(...) }
       end
-
-      ::Object.include WithinOther
     end
   end
 end
+
+module Bridgetown
+  module Refinements
+    include Foundation::RefineExt::Object
+  end
+end
diff --git a/bridgetown-foundation/lib/bridgetown/foundation/refine_ext/string.rb b/bridgetown-foundation/lib/bridgetown/foundation/refine_ext/string.rb
new file mode 100644
index 000000000..bf9450b4d
--- /dev/null
+++ b/bridgetown-foundation/lib/bridgetown/foundation/refine_ext/string.rb
@@ -0,0 +1,37 @@
+# frozen_string_literal: true
+
+module Bridgetown::Foundation
+  module RefineExt
+    module String
+      refine ::String do
+        def indent!(indent_by, *args)
+          if args.length.positive?
+            Kernel.warn "multiple arguments aren't supported by `indent!' in Bridgetown", uplevel: 1
+          end
+
+          gsub! %r!^(?\!$)!, " " * indent_by
+        end
+
+        def indent(indent_by, *args)
+          if args.length.positive?
+            Kernel.warn "multiple arguments aren't supported by `indent' in Bridgetown", uplevel: 1
+          end
+
+          dup.indent!(indent_by)
+        end
+
+        def questionable = Bridgetown::Foundation::QuestionableString.new(self)
+
+        def inquiry = Bridgetown::Foundation.deprecation_warning(
+          self, :inquiry, :questionable, 2024, 12
+        ).then { questionable }
+      end
+    end
+  end
+end
+
+module Bridgetown
+  module Refinements
+    include Foundation::RefineExt::String
+  end
+end
diff --git a/bridgetown-foundation/lib/bridgetown/foundation/refine_ext/symbol.rb b/bridgetown-foundation/lib/bridgetown/foundation/refine_ext/symbol.rb
new file mode 100644
index 000000000..e2a65fc0d
--- /dev/null
+++ b/bridgetown-foundation/lib/bridgetown/foundation/refine_ext/symbol.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+module Bridgetown::Foundation
+  module RefineExt
+    module Symbol
+      refine ::Symbol do
+        def with(...)
+          ->(caller, *rest) { caller.public_send(self, *rest, ...) }
+        end
+
+        def call(...)
+          ->(caller, *rest) { caller.public_send(self, *rest).public_send(...) }
+        end
+      end
+    end
+  end
+end
+
+module Bridgetown
+  module Refinements
+    include Foundation::RefineExt::Symbol
+  end
+end
diff --git a/bridgetown-foundation/test/test_string.rb b/bridgetown-foundation/test/test_string.rb
index 5597e644b..4b126dccc 100644
--- a/bridgetown-foundation/test/test_string.rb
+++ b/bridgetown-foundation/test/test_string.rb
@@ -3,6 +3,8 @@
 require "test_helper"
 
 class TestString < Minitest::Test
+  using Bridgetown::Refinements
+
   def test_that_it_has_a_version_number
     refute_nil ::Bridgetown::Foundation::VERSION
   end
@@ -31,4 +33,10 @@ def test_starts_ends_with
     assert "this".ends_with?("is")
     refute "this".ends_with?("si")
   end
+
+  # TODO: more testing of other data types
+  def test_within
+    assert "abc".within? ["def", "abc"]
+    refute "abc".within? ["def"]
+  end
 end