diff --git a/internal/corazawaf/rule.go b/internal/corazawaf/rule.go
index bfc700f7..4e04ff8d 100644
--- a/internal/corazawaf/rule.go
+++ b/internal/corazawaf/rule.go
@@ -586,18 +586,22 @@ func (r *Rule) AddVariableNegation(v variables.RuleVariable, key string) error {
 }
 
 var transformationIDToName = []string{""}
-var transformationNameToID = sync.Map{} // map[string]int
+var transformationNameToID = map[string]int{"": 0}
+var transformationIDsLock = sync.Mutex{}
 
 func transformationID(currentID int, transformationName string) int {
+	transformationIDsLock.Lock()
+	defer transformationIDsLock.Unlock()
+
 	currName := transformationIDToName[currentID]
 	nextName := fmt.Sprintf("%s+%s", currName, transformationName)
-	if id, ok := transformationNameToID.Load(nextName); ok {
-		return id.(int)
+	if id, ok := transformationNameToID[nextName]; ok {
+		return id
 	}
 
 	id := len(transformationIDToName)
 	transformationIDToName = append(transformationIDToName, nextName)
-	transformationNameToID.Store(nextName, id)
+	transformationNameToID[nextName] = id
 	return id
 }
 
diff --git a/internal/corazawaf/rule_test.go b/internal/corazawaf/rule_test.go
index f96eb402..d999bb0c 100644
--- a/internal/corazawaf/rule_test.go
+++ b/internal/corazawaf/rule_test.go
@@ -384,40 +384,6 @@ func TestAddTransformation(t *testing.T) {
 	}
 }
 
-func BenchmarkAddTransformationUnique(b *testing.B) {
-	transformation := func(input string) (string, bool, error) {
-		return "Test", true, nil
-	}
-	b.ResetTimer()
-	b.RunParallel(func(p *testing.PB) {
-		rule := NewRule()
-		for p.Next() {
-			transformationName := "transformation" + b.Name()
-			err := rule.AddTransformation(transformationName, transformation)
-			if err != nil {
-				b.Fatalf("Failed to add a transformation: %s", err.Error())
-			}
-		}
-	})
-}
-
-func BenchmarkAddTransformationSame(b *testing.B) {
-	transformation := func(input string) (string, bool, error) {
-		return "Test", true, nil
-	}
-	b.ResetTimer()
-	b.RunParallel(func(p *testing.PB) {
-		for p.Next() {
-			rule := NewRule()
-			transformationName := "transformation"
-			err := rule.AddTransformation(transformationName, transformation)
-			if err != nil {
-				b.Fatalf("Failed to add a transformation: %s", err.Error())
-			}
-		}
-	})
-}
-
 func TestAddTransformationEmpty(t *testing.T) {
 	rule := NewRule()
 	transformationName := ""