diff --git a/mapset/go.mod b/mapset/go.mod
new file mode 100644
index 0000000..e0a758f
--- /dev/null
+++ b/mapset/go.mod
@@ -0,0 +1,3 @@
+module git.blauwelle.com/go/crate/mapset
+
+go 1.20
diff --git a/mapset/mapset.go b/mapset/mapset.go
new file mode 100644
index 0000000..8535146
--- /dev/null
+++ b/mapset/mapset.go
@@ -0,0 +1,294 @@
+package mapset
+
+import (
+	"encoding/json"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// New 返回 [MapSet]
+func New[T comparable](keys ...T) MapSet[T] {
+	s := make(MapSet[T], len(keys))
+	s.AddMany(keys...)
+	return s
+}
+
+// MapSet 是集合的范型实现
+type MapSet[T comparable] map[T]struct{}
+
+// Cardinality 返回集合的元素个数
+func (s MapSet[T]) Cardinality() int {
+	return len(s)
+}
+
+// AddOne 添加元素到集合
+func (s MapSet[T]) AddOne(key T) {
+	s[key] = struct{}{}
+}
+
+// AddOneOk 添加元素到集合并返回是否添加成功
+func (s MapSet[T]) AddOneOk(key T) bool {
+	size := len(s)
+	s[key] = struct{}{}
+	return len(s) > size
+}
+
+// AddMany 添加多个元素到集合
+func (s MapSet[T]) AddMany(keys ...T) {
+	for _, key := range keys {
+		s[key] = struct{}{}
+	}
+}
+
+// AddManyOk 添加多个元素到集合并返回添加成功的个数
+func (s MapSet[T]) AddManyOk(keys ...T) int {
+	size := len(s)
+	for _, key := range keys {
+		s[key] = struct{}{}
+	}
+	return len(s) - size
+}
+
+// DeleteOne 从集合中删除元素
+func (s MapSet[T]) DeleteOne(key T) {
+	delete(s, key)
+}
+
+// DeleteOneOk 从集合中删除元素并返回是否删除成功
+func (s MapSet[T]) DeleteOneOk(key T) bool {
+	size := len(s)
+	delete(s, key)
+	return size > len(s)
+}
+
+// DeleteMany 从集合删除多个元素
+func (s MapSet[T]) DeleteMany(keys ...T) {
+	for _, key := range keys {
+		delete(s, key)
+	}
+}
+
+// DeleteManyOk 从集合删除多个元素并返回成功删除的个数
+func (s MapSet[T]) DeleteManyOk(keys ...T) int {
+	size := len(s)
+	for _, key := range keys {
+		delete(s, key)
+	}
+	return size - len(s)
+}
+
+// PopOne 从集合中删除1个元素, 并把被删除的元素返回
+func (s MapSet[T]) PopOne() (key T, ok bool) {
+	for k := range s {
+		key, ok = k, true
+		return
+	}
+	return
+}
+
+// Clear 清空集合
+func (s MapSet[T]) Clear() {
+	for key := range s {
+		delete(s, key)
+	}
+}
+
+// Clone 返回集合的浅拷贝
+func (s MapSet[T]) Clone() MapSet[T] {
+	n := make(MapSet[T], len(s))
+	for key := range s {
+		n[key] = struct{}{}
+	}
+	return n
+}
+
+// IsEmpty 判断集合是否为空
+func (s MapSet[T]) IsEmpty() bool {
+	return len(s) == 0
+}
+
+// Equal 判断集合是否和另1个集合相等
+func (s MapSet[T]) Equal(o MapSet[T]) bool {
+	if len(s) != len(o) {
+		return false
+	}
+	for key := range s {
+		if _, exists := o[key]; !exists {
+			return false
+		}
+	}
+	return true
+}
+
+// ContainsOne 判断集合是否包含1个元素
+func (s MapSet[T]) ContainsOne(key T) bool {
+	_, exists := s[key]
+	return exists
+}
+
+// ContainsAll 判断集合是否包含全部元素
+// 参数为空时返回 true
+func (s MapSet[T]) ContainsAll(keys ...T) bool {
+	for _, key := range keys {
+		if _, exists := s[key]; !exists {
+			return false
+		}
+	}
+	return true
+}
+
+// ContainsAny 判断集合是否包含任意元素
+// 参数为空时返回 false
+func (s MapSet[T]) ContainsAny(keys ...T) bool {
+	for _, key := range keys {
+		if _, exists := s[key]; exists {
+			return true
+		}
+	}
+	return false
+}
+
+// IsSubsetOf 判断集合是否是另1个集合的子集
+func (s MapSet[T]) IsSubsetOf(o MapSet[T]) bool {
+	if len(s) > len(o) {
+		return false
+	}
+	for key := range s {
+		if _, exists := o[key]; !exists {
+			return false
+		}
+	}
+	return true
+}
+
+// IsProperSubsetOf 判断集合是否是另1个集合的真子集
+func (s MapSet[T]) IsProperSubsetOf(o MapSet[T]) bool {
+	if len(s) >= len(o) {
+		return false
+	}
+	for key := range s {
+		if _, exists := o[key]; !exists {
+			return false
+		}
+	}
+	return true
+}
+
+// Union 返回集合和另1个集合的并集
+func (s MapSet[T]) Union(o MapSet[T]) MapSet[T] {
+	r := make(MapSet[T], maxInt(len(s), len(o)))
+	for key := range s {
+		r[key] = struct{}{}
+	}
+	for key := range o {
+		r[key] = struct{}{}
+	}
+	return r
+}
+
+// Intersection 返回集合和另1个集合的交集
+func (s MapSet[T]) Intersection(o MapSet[T]) MapSet[T] {
+	a, b := s, o
+	if len(a) > len(b) {
+		a, b = b, a
+	}
+	r := make(MapSet[T], len(a))
+	for key := range a {
+		if _, exists := b[key]; exists {
+			r[key] = struct{}{}
+		}
+	}
+	return r
+}
+
+// Difference 返回集合和另1个集合的差集
+func (s MapSet[T]) Difference(o MapSet[T]) MapSet[T] {
+	r := make(MapSet[T])
+	for key := range s {
+		if _, exists := o[key]; !exists {
+			r[key] = struct{}{}
+		}
+	}
+	return r
+}
+
+// SymmetricDifference 返回集合和另1个集合相互差集的并集
+func (s MapSet[T]) SymmetricDifference(o MapSet[T]) MapSet[T] {
+	r := make(MapSet[T])
+	for key := range s {
+		if _, exists := o[key]; !exists {
+			r[key] = struct{}{}
+		}
+	}
+	for key := range o {
+		if _, exists := s[key]; !exists {
+			r[key] = struct{}{}
+		}
+	}
+	return r
+}
+
+// ToSlice 把集合转换成切片
+func (s MapSet[T]) ToSlice() []T {
+	keys := make([]T, 0, len(s))
+	for key := range s {
+		keys = append(keys, key)
+	}
+	return keys
+}
+
+// ToAnySlice 把集合转换成 []any
+func (s MapSet[T]) ToAnySlice() []any {
+	keys := make([]any, 0, len(s))
+	for key := range s {
+		keys = append(keys, key)
+	}
+	return keys
+}
+
+// MarshalJSON 实现 [encoding/json.Marshaler]
+func (s MapSet[T]) MarshalJSON() ([]byte, error) {
+	return json.Marshal(s.ToSlice())
+}
+
+// UnmarshalJSON 实现 [encoding/json.Unmarshaler]
+func (s *MapSet[T]) UnmarshalJSON(b []byte) error {
+	var keys []T
+	if *s == nil {
+		*s = New[T]()
+	}
+	if err := json.Unmarshal(b, &keys); err != nil {
+		return err
+	}
+	s.AddMany(keys...)
+	return nil
+}
+
+func (s MapSet[T]) String() string {
+	size := s.Cardinality()
+	if size > 64 {
+		size = 64
+	}
+	keys := make([]string, 0, size)
+	for key := range s {
+		switch any(key).(type) {
+		case string:
+			keys = append(keys, fmt.Sprintf("%q", any(key)))
+		default:
+			keys = append(keys, fmt.Sprintf("%v", any(key)))
+		}
+		size--
+		if size == 0 {
+			break
+		}
+	}
+	return "MapSet(" + strconv.Itoa(s.Cardinality()) + "){" + strings.Join(keys, ",") + "}"
+}
+
+func maxInt(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}
diff --git a/mapset/mapset_test.go b/mapset/mapset_test.go
new file mode 100644
index 0000000..c796ed9
--- /dev/null
+++ b/mapset/mapset_test.go
@@ -0,0 +1,523 @@
+package mapset_test
+
+import (
+	"encoding/json"
+	"sort"
+	"testing"
+
+	"git.blauwelle.com/go/crate/mapset"
+)
+
+func TestNewEmpty(t *testing.T) {
+	s := mapset.New[int]()
+	if size := s.Cardinality(); size != 0 {
+		t.Fatalf("got %d, want cardinality 0", size)
+	}
+}
+
+func TestNew(t *testing.T) {
+	s := mapset.New(1, 2, 3, 4, 5)
+	if size := s.Cardinality(); size != 5 {
+		t.Fatalf("got %d, want cardinality 5", size)
+	}
+	keys := make([]int, 0, 10)
+	for i := 1; i < 6; i++ {
+		keys = append(keys, i)
+		if ok := s.ContainsOne(i); !ok {
+			t.Fatalf("got false, want contains %d", i)
+		}
+	}
+	if ok := s.ContainsAll(keys...); !ok {
+		t.Fatalf("want contains all of %v", keys)
+	}
+	for i := 6; i < 11; i++ {
+		keys = append(keys, i)
+		if ok := s.ContainsOne(i); ok {
+			t.Fatalf("want do not contain %d", i)
+		}
+	}
+	if ok := s.ContainsAll(keys...); ok {
+		t.Fatalf("want do not contain all of %v", keys)
+	}
+	if ok := s.ContainsAny(keys...); !ok {
+		t.Fatalf("want contains any of %v", keys)
+	}
+}
+
+func TestAddOne(t *testing.T) {
+	s := mapset.New[int]()
+	s.AddOne(1)
+	if size := s.Cardinality(); size != 1 {
+		t.Fatalf("got %d, want cardinality 1", size)
+	}
+	if ok := s.ContainsOne(1); !ok {
+		t.Fatalf("want contains 1")
+	}
+}
+
+func TestAddOneOk(t *testing.T) {
+	t.Run("ok", func(t *testing.T) {
+		s := mapset.New[int]()
+		ok := s.AddOneOk(1)
+		if size := s.Cardinality(); size != 1 {
+			t.Fatalf("got %d, want cardinality 1", size)
+		}
+		if !ok {
+			t.Fatalf("fail")
+		}
+		if ok := s.ContainsOne(1); !ok {
+			t.Fatalf("want contains 1")
+		}
+	})
+	t.Run("exists", func(t *testing.T) {
+		s := mapset.New[int](1)
+		ok := s.AddOneOk(1)
+		if size := s.Cardinality(); size != 1 {
+			t.Fatalf("got %d, want cardinality 1", size)
+		}
+		if ok {
+			t.Fatalf("fail")
+		}
+		if ok := s.ContainsOne(1); !ok {
+			t.Fatalf("want contains 1")
+		}
+	})
+}
+
+func TestAddManyOk(t *testing.T) {
+	t.Run("ok", func(t *testing.T) {
+		s := mapset.New[int]()
+		n := s.AddManyOk(1, 2, 3)
+		if n != 3 {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("exists", func(t *testing.T) {
+		s := mapset.New(1, 2)
+		n := s.AddManyOk(1, 2, 3, 4)
+		if n != 2 {
+			t.Fatalf("fail")
+		}
+	})
+}
+
+func TestDeleteOneOk(t *testing.T) {
+	t.Run("ok", func(t *testing.T) {
+		s := mapset.New(1, 2, 3)
+		ok := s.DeleteOneOk(1)
+		if !ok {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("not_exists", func(t *testing.T) {
+		s := mapset.New(1, 2, 3)
+		ok := s.DeleteOneOk(4)
+		if ok {
+			t.Fatalf("faila")
+		}
+	})
+}
+
+func TestDeleteManyOk(t *testing.T) {
+	t.Run("ok", func(t *testing.T) {
+		s := mapset.New(1, 2, 3)
+		n := s.DeleteManyOk(1, 2, 3)
+		if n != 3 {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("delete_more", func(t *testing.T) {
+		s := mapset.New(1, 2, 3)
+		n := s.DeleteManyOk(1, 2, 3, 4)
+		if n != 3 {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("delete_partial", func(t *testing.T) {
+		s := mapset.New(1, 2, 3)
+		n := s.DeleteManyOk(1, 2, 4)
+		if n != 2 {
+			t.Fatalf("fail")
+		}
+	})
+}
+
+func TestDelete(t *testing.T) {
+	s := mapset.New(1)
+	s.DeleteOne(1)
+	if size := s.Cardinality(); size != 0 {
+		t.Fatalf("got %d, want cardinality 0", size)
+	}
+}
+
+func TestDeleteMany(t *testing.T) {
+	s := mapset.New(1, 2, 3)
+	s.DeleteMany(1, 3)
+	if size := s.Cardinality(); size != 1 {
+		t.Fatalf("got %d, want cardinality 1", size)
+	}
+}
+
+func TestContainsAny(t *testing.T) {
+	s := mapset.New(1, 2, 3)
+	if ok := s.ContainsAny(); ok {
+		t.Fatalf("got true, should not contains empty")
+	}
+	if ok := s.ContainsAny(-1, -2); ok {
+		t.Fatalf("got true, should not contains any of -1, -2")
+	}
+}
+
+func TestPopOne(t *testing.T) {
+	s := mapset.New[int]()
+	if _, ok := s.PopOne(); ok {
+		t.Fatalf("should not pop any key")
+	}
+	s.AddMany(1, 2, 3)
+	if key, ok := s.PopOne(); !ok {
+		t.Fatalf("should pop 1 key")
+	} else if key < 1 || key > 3 {
+		t.Fatalf("wrong key")
+	}
+}
+
+func TestClear(t *testing.T) {
+	s := mapset.New(1, 2, 3)
+	s.Clear()
+	if size := s.Cardinality(); size != 0 {
+		t.Fatalf("got %d, want 0 cardinality after clean", size)
+	}
+}
+
+func TestClone(t *testing.T) {
+	s := mapset.New(1, 2)
+	c := s.Clone()
+	if ok := s.Equal(c); !ok {
+		t.Fatalf("got false, want equal")
+	}
+	s.AddOne(3)
+	if size := c.Cardinality(); size != 2 {
+		t.Fatalf("got %d, want 2", size)
+	}
+	if ok := s.Equal(c); ok {
+		t.Fatalf("got true, want not equal")
+	}
+}
+
+func TestIsEmpty(t *testing.T) {
+	t.Run("empty", func(t *testing.T) {
+		s := mapset.New[int]()
+		if ok := s.IsEmpty(); !ok {
+			t.Fatalf("got false, want empty")
+		}
+	})
+	t.Run("not_empty", func(t *testing.T) {
+		s := mapset.New(1)
+		if ok := s.IsEmpty(); ok {
+			t.Fatalf("got true, want not empty")
+		}
+	})
+}
+
+func TestEqual(t *testing.T) {
+	s := mapset.New(1, 2)
+	c := mapset.New(1, 2)
+	v := mapset.New(1, 2, 3)
+	p := mapset.New(2, 3)
+	t.Run("equal", func(t *testing.T) {
+		if ok := s.Equal(c); !ok {
+			t.Fatalf("got false, want equal")
+		}
+	})
+	t.Run("not_equal_1", func(t *testing.T) {
+		if ok := s.Equal(v); ok {
+			t.Fatalf("got true, want not equal")
+		}
+	})
+	t.Run("not_equal_2", func(t *testing.T) {
+		if ok := s.Equal(p); ok {
+			t.Fatalf("got true, want not equal")
+		}
+	})
+}
+
+func TestIsSubsetOf(t *testing.T) {
+	s := mapset.New(1, 2)
+	c := mapset.New(1, 2, 3)
+	v := mapset.New(2, 3)
+	e := mapset.New[int]()
+	t.Run("is_subset_of_self", func(t *testing.T) {
+		if ok := s.IsSubsetOf(s); !ok {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("is_subset", func(t *testing.T) {
+		if ok := s.IsSubsetOf(c); !ok {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("not_subset_1", func(t *testing.T) {
+		if ok := s.IsSubsetOf(v); ok {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("not_subset_2", func(t *testing.T) {
+		if ok := c.IsSubsetOf(s); ok {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("empty_is_subset_of_empty", func(t *testing.T) {
+		if ok := e.IsSubsetOf(e); !ok {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("empty_is_subset_of_other", func(t *testing.T) {
+		if ok := e.IsSubsetOf(s); !ok {
+			t.Fatalf("fail")
+		}
+	})
+}
+
+func TestIsProperSubsetOf(t *testing.T) {
+	s := mapset.New(1, 2)
+	c := mapset.New(1, 2, 3)
+	v := mapset.New(2, 3)
+	p := mapset.New(1, 3, 5, 7)
+	t.Run("not_proper_subset_of_self", func(t *testing.T) {
+		if ok := s.IsProperSubsetOf(s); ok {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("is_proper_subset", func(t *testing.T) {
+		if ok := s.IsProperSubsetOf(c); !ok {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("not_proper_subset_1", func(t *testing.T) {
+		if ok := s.IsProperSubsetOf(v); ok {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("not_proper_subset_2", func(t *testing.T) {
+		if ok := c.IsProperSubsetOf(s); ok {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("not_proper_subset_3", func(t *testing.T) {
+		if ok := s.IsProperSubsetOf(p); ok {
+			t.Fatalf("fail")
+		}
+	})
+}
+
+func TestUnion(t *testing.T) {
+	t.Run("union_1", func(t *testing.T) {
+		s := mapset.New(1, 2)
+		c := mapset.New(2, 3)
+		u := mapset.New(1, 2, 3)
+		if g := s.Union(c); !g.Equal(u) {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("union_2", func(t *testing.T) {
+		s := mapset.New(1, 2, 5, 7)
+		c := mapset.New(2, 3)
+		u := mapset.New(1, 2, 3, 5, 7)
+		if g := s.Union(c); !g.Equal(u) {
+			t.Fatalf("fail")
+		}
+	})
+}
+
+func TestIntersection(t *testing.T) {
+	t.Run("intersection_1", func(t *testing.T) {
+		s := mapset.New(1, 2)
+		c := mapset.New(2, 3)
+		u := mapset.New(2)
+		if g := s.Intersection(c); !g.Equal(u) {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("intersection_2", func(t *testing.T) {
+		s := mapset.New(1, 2, 4)
+		c := mapset.New(2, 3)
+		u := mapset.New(2)
+		if g := s.Intersection(c); !g.Equal(u) {
+			t.Fatalf("fail")
+		}
+	})
+}
+
+func TestDifference(t *testing.T) {
+	s := mapset.New(1, 2, 3)
+	c := mapset.New(1, 2)
+	t.Run("diff_1", func(t *testing.T) {
+		o := s.Difference(c)
+		if !o.Equal(mapset.New(3)) {
+			t.Fatalf("fail")
+		}
+	})
+}
+
+func TestSymmetricDifference(t *testing.T) {
+	s := mapset.New(1, 2, 3)
+	c := mapset.New(1, 2, 4)
+	t.Run("diff_1", func(t *testing.T) {
+		o := s.SymmetricDifference(c)
+		if !o.Equal(mapset.New(3, 4)) {
+			t.Fatalf("fail")
+		}
+	})
+}
+
+func TestToSlice(t *testing.T) {
+	s := mapset.New(1, 2, 3)
+	r := s.ToSlice()
+	sort.Ints(r)
+	if size := len(r); size != 3 {
+		t.Fatalf("got %d, want 3", size)
+	}
+	if !([3]int(r) == [3]int{1, 2, 3}) {
+		t.Fatalf("fail")
+	}
+}
+
+func TestToAnySlice(t *testing.T) {
+	s := mapset.New(1, 2, 3)
+	r := s.ToAnySlice()
+	if size := len(r); size != 3 {
+		t.Fatalf("got %d, want 3", size)
+	}
+	sort.Slice(r, func(i, j int) bool {
+		return r[i].(int) < r[j].(int)
+	})
+	if !([3]any(r) == [3]any{1, 2, 3}) {
+		t.Fatalf("fail")
+	}
+}
+
+func TestString(t *testing.T) {
+	t.Run("int", func(t *testing.T) {
+		s := mapset.New(1, 2, 3)
+		str := s.String()
+		t.Log(str)
+	})
+	t.Run("int_large", func(t *testing.T) {
+		s := mapset.New[int]()
+		for i := 0; i < 80; i++ {
+			s.AddOne(i)
+		}
+		str := s.String()
+		t.Log(str)
+	})
+	t.Run("string", func(t *testing.T) {
+		s := mapset.New("a", "aa,bb", `"cc"`)
+		t.Log(s.String())
+	})
+}
+
+func TestMarshalUnmarshal(t *testing.T) {
+	t.Run("marshal", func(t *testing.T) {
+		s := mapset.New(1)
+		b, err := json.Marshal(s)
+		if err != nil {
+			t.Fatalf("err: %v", err)
+		}
+		if string(b) != "[1]" {
+			t.Fatalf("fail")
+		}
+	})
+	t.Run("unmarshal", func(t *testing.T) {
+		b := []byte(`[1, 2]`)
+		var s mapset.MapSet[int]
+		if err := json.Unmarshal(b, &s); err != nil {
+			t.Fatalf("err: %v", err)
+		}
+		if !s.Equal(mapset.New(1, 2)) {
+			t.Fatalf("failed")
+		}
+	})
+	t.Run("unmarshal_error", func(t *testing.T) {
+		b := []byte(`1`)
+		var s mapset.MapSet[int]
+		if err := json.Unmarshal(b, &s); err == nil {
+			t.Fatalf("fail")
+		}
+	})
+}
+
+func BenchmarkAdd(b *testing.B) {
+	size := 1024 * 1
+	s := mapset.New[int]()
+	keys := make([]int, size)
+	for i := 0; i < size; i++ {
+		s.AddOne(i)
+		keys[i] = i
+	}
+	b.Run("addOne", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			for i := 0; i < size; i++ {
+				s.AddOne(i)
+			}
+		}
+	})
+	b.Run("addMany", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			for i := 0; i < size; i++ {
+				keys[i] = i
+			}
+			s.AddMany(keys...)
+		}
+	})
+	b.Run("addManyPrepared", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			s.AddMany(keys...)
+		}
+	})
+}
+
+func BenchmarkContains(b *testing.B) {
+	s := mapset.New[int]()
+	for i := 0; i < 1024; i++ {
+		s.AddOne(i)
+	}
+	b.Run("containsAll_keyExists", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			s.ContainsAll(1)
+		}
+	})
+	b.Run("containsAll_keyNotExists", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			s.ContainsAll(-1)
+		}
+	})
+	b.Run("containsOne_keyExists", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			s.ContainsOne(1)
+		}
+	})
+	b.Run("containsOne_keyNotExists", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			s.ContainsOne(-1)
+		}
+	})
+}
+
+func BenchmarkRaw(b *testing.B) {
+	b.Run("raw-64", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			m := map[int]struct{}{}
+			for j := 0; j < 64; j++ {
+				m[j] = struct{}{}
+			}
+		}
+	})
+	b.Run("mapset-64", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			s := mapset.New[int]()
+			for j := 0; j < 64; j++ {
+				s.AddOne(j)
+			}
+		}
+	})
+}