diff --git a/benchmarks/ostruct.yml b/benchmarks/ostruct.yml
new file mode 100644
index 0000000..26c2185
--- /dev/null
+++ b/benchmarks/ostruct.yml
@@ -0,0 +1,154 @@
+prelude: |
+  # frozen_string_literal: true
+
+  require "ostruct"
+  keys = (0..29).map { :"method_#{_1}" }
+  input = keys.to_h { [_1, _1] }
+
+benchmark:
+  new: |
+    OpenStruct.new(input)
+
+  attr_write_read: |
+    ostruct = OpenStruct.new
+    ostruct.method_0 = "foo"
+    ostruct.method_1 = "bar"
+    ostruct.method_2 = "baz"
+    ostruct.method_3 = "quux"
+    ostruct.method_4 = "foo"
+    ostruct.method_5 = "bar"
+    ostruct.method_6 = "baz"
+    ostruct.method_7 = "quux"
+    ostruct.method_8 = "quux"
+    ostruct.method_9 = "quux"
+    ostruct.method_10 = "foo"
+    ostruct.method_11 = "bar"
+    ostruct.method_12 = "baz"
+    ostruct.method_13 = "quux"
+    ostruct.method_14 = "foo"
+    ostruct.method_15 = "bar"
+    ostruct.method_16 = "baz"
+    ostruct.method_17 = "quux"
+    ostruct.method_18 = "quux"
+    ostruct.method_19 = "quux"
+    ostruct.method_20 = "foo"
+    ostruct.method_21 = "bar"
+    ostruct.method_22 = "baz"
+    ostruct.method_23 = "quux"
+    ostruct.method_24 = "foo"
+    ostruct.method_25 = "bar"
+    ostruct.method_26 = "baz"
+    ostruct.method_27 = "quux"
+    ostruct.method_28 = "quux"
+    ostruct.method_29 = "quux"
+    ostruct.method_0
+    ostruct.method_1
+    ostruct.method_2
+    ostruct.method_3
+    ostruct.method_4
+    ostruct.method_5
+    ostruct.method_6
+    ostruct.method_7
+    ostruct.method_8
+    ostruct.method_9
+    ostruct.method_10
+    ostruct.method_11
+    ostruct.method_12
+    ostruct.method_13
+    ostruct.method_14
+    ostruct.method_15
+    ostruct.method_16
+    ostruct.method_17
+    ostruct.method_18
+    ostruct.method_19
+    ostruct.method_20
+    ostruct.method_21
+    ostruct.method_22
+    ostruct.method_23
+    ostruct.method_24
+    ostruct.method_25
+    ostruct.method_26
+    ostruct.method_27
+    ostruct.method_28
+    ostruct.method_29
+
+  index_write_attr_read: |
+    ostruct = OpenStruct.new
+    keys.each_with_index do ostruct[_1] = _2 end
+    keys.each do ostruct.send(_1) end
+
+  index_write_attr_read: |
+    ostruct = OpenStruct.new
+    keys.each_with_index do ostruct[_1] = _2 end
+    keys.each do ostruct.send(_1) end
+
+  null_reads: |
+    ostruct = OpenStruct.new
+    ostruct.method_0
+    ostruct.method_1
+    ostruct.method_2
+    ostruct.method_3
+    ostruct.method_4
+    ostruct.method_5
+    ostruct.method_6
+    ostruct.method_7
+    ostruct.method_8
+    ostruct.method_9
+    ostruct.method_10
+    ostruct.method_11
+    ostruct.method_12
+    ostruct.method_13
+    ostruct.method_14
+    ostruct.method_15
+    ostruct.method_16
+    ostruct.method_17
+    ostruct.method_18
+    ostruct.method_19
+    ostruct.method_20
+    ostruct.method_21
+    ostruct.method_22
+    ostruct.method_23
+    ostruct.method_24
+    ostruct.method_25
+    ostruct.method_26
+    ostruct.method_27
+    ostruct.method_28
+    ostruct.method_29
+
+  10x_reads: |
+    ostruct = OpenStruct.new(input)
+    10.times do
+      ostruct.method_0
+      ostruct.method_1
+      ostruct.method_2
+      ostruct.method_3
+      ostruct.method_4
+      ostruct.method_5
+      ostruct.method_6
+      ostruct.method_7
+      ostruct.method_8
+      ostruct.method_9
+    end
+
+  100x_reads: |
+    ostruct = OpenStruct.new(input)
+    100.times do
+      ostruct.method_0
+      ostruct.method_1
+      ostruct.method_2
+      ostruct.method_3
+      ostruct.method_4
+      ostruct.method_5
+      ostruct.method_6
+      ostruct.method_7
+      ostruct.method_8
+      ostruct.method_9
+    end
+
+contexts:
+  - name: v0.6.0
+    gems:
+      ostruct: 0.6.0
+  - name: local
+    prelude: |
+      $LOAD_PATH.unshift "./lib"
diff --git a/lib/ostruct.rb b/lib/ostruct.rb
index 3793e5d..09f4c8c 100644
--- a/lib/ostruct.rb
+++ b/lib/ostruct.rb
@@ -231,7 +231,7 @@ def marshal_dump # :nodoc:
   # OpenStruct. It does this by using the metaprogramming function
   # define_singleton_method for both the getter method and the setter method.
   #
-  def new_ostruct_member!(name) # :nodoc:
+  def override_ostruct_method!(name) # :nodoc:
     unless @table.key?(name) || is_method_protected!(name)
       if defined?(::Ractor)
         getter_proc = nil.instance_eval{ Proc.new { @table[name] } }
@@ -246,11 +246,11 @@ def new_ostruct_member!(name) # :nodoc:
       define_singleton_method!("#{name}=", &setter_proc)
     end
   end
-  private :new_ostruct_member!
+  private :override_ostruct_method!
 
   private def is_method_protected!(name) # :nodoc:
     if !respond_to?(name, true)
-      false
+      true
     elsif name.match?(/!$/)
       true
     else
@@ -271,6 +271,29 @@ def freeze
     super
   end
 
+  def singleton_methods(*) # :nodoc:
+    (super + @table.keys.flat_map {|k| [k, :"#{k}="] }).uniq
+  end
+
+  def methods(*) # :nodoc:
+    (super + @table.keys.flat_map {|k| [k, :"#{k}="] }).uniq
+  end
+
+  def respond_to_missing?(mid, *) # :nodoc:
+    if (mname = mid[/.*(?==\z)/m])
+      @table&.key?(mname.to_sym)
+    elsif @table&.key?(mid)
+      true
+    else
+      begin
+        super
+      rescue NoMethodError => err
+        err.backtrace.shift
+        raise!
+      end
+    end
+  end
+
   private def method_missing(mid, *args) # :nodoc:
     len = args.length
     if mname = mid[/.*(?==\z)/m]
@@ -317,7 +340,7 @@ def [](name)
   #
   def []=(name, value)
     name = name.to_sym
-    new_ostruct_member!(name)
+    override_ostruct_method!(name)
     @table[name] = value
   end
   alias_method :set_ostruct_member_value!, :[]=
diff --git a/test/ostruct/test_ostruct.rb b/test/ostruct/test_ostruct.rb
index 19bb606..78a794d 100644
--- a/test/ostruct/test_ostruct.rb
+++ b/test/ostruct/test_ostruct.rb
@@ -195,6 +195,7 @@ def test_accessor_defines_method
     assert_respond_to(os, :foo)
     assert_equal(42, os.foo)
     assert_equal([:foo, :foo=], os.singleton_methods.sort)
+    assert_equal([:foo, :foo=], os.methods(false).sort)
   end
 
   def test_does_not_redefine