diff --git a/dist/index.js b/dist/index.js
index 5c3e27c2..11280627 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -376,14 +376,14 @@ var NodeUtils = function () {
                             value = node;
                         } else {
                             value = Node_1.Node.getProgramNode([node]);
-                            value['parentNode'] = value;
+                            value.parentNode = value;
                         }
                         isRootNode = false;
                     } else {
                         value = parentNode || node;
                     }
-                    node['parentNode'] = value;
-                    node['obfuscated'] = false;
+                    node.parentNode = value;
+                    node.obfuscated = false;
                 }
             });
         }
@@ -1539,7 +1539,6 @@ var Obfuscator = function () {
     return Obfuscator;
 }();
 
-Obfuscator.counter = 0;
 Obfuscator.nodeGroups = [DomainLockNodesGroup_1.DomainLockNodesGroup, SelfDefendingNodesGroup_1.SelfDefendingNodesGroup, ConsoleOutputNodesGroup_1.ConsoleOutputNodesGroup, DebugProtectionNodesGroup_1.DebugProtectionNodesGroup, UnicodeArrayNodesGroup_1.UnicodeArrayNodesGroup];
 Obfuscator.nodeObfuscators = new Map([[NodeType_1.NodeType.ArrowFunctionExpression, [FunctionObfuscator_1.FunctionObfuscator]], [NodeType_1.NodeType.ClassDeclaration, [FunctionDeclarationObfuscator_1.FunctionDeclarationObfuscator]], [NodeType_1.NodeType.CatchClause, [CatchClauseObfuscator_1.CatchClauseObfuscator]], [NodeType_1.NodeType.FunctionDeclaration, [FunctionDeclarationObfuscator_1.FunctionDeclarationObfuscator, FunctionObfuscator_1.FunctionObfuscator]], [NodeType_1.NodeType.FunctionExpression, [FunctionObfuscator_1.FunctionObfuscator]], [NodeType_1.NodeType.MemberExpression, [MemberExpressionObfuscator_1.MemberExpressionObfuscator]], [NodeType_1.NodeType.MethodDefinition, [MethodDefinitionObfuscator_1.MethodDefinitionObfuscator]], [NodeType_1.NodeType.ObjectExpression, [ObjectExpressionObfuscator_1.ObjectExpressionObfuscator]], [NodeType_1.NodeType.VariableDeclaration, [VariableDeclarationObfuscator_1.VariableDeclarationObfuscator]], [NodeType_1.NodeType.Literal, [LiteralObfuscator_1.LiteralObfuscator]]]);
 exports.Obfuscator = Obfuscator;
diff --git a/src/Obfuscator.ts b/src/Obfuscator.ts
index e3373c74..5f5e2a8d 100644
--- a/src/Obfuscator.ts
+++ b/src/Obfuscator.ts
@@ -31,8 +31,6 @@ import { VariableDeclarationObfuscator } from './node-obfuscators/VariableDeclar
 import { StackTraceAnalyzer } from './stack-trace-analyzer/StackTraceAnalyzer';
 
 export class Obfuscator implements IObfuscator {
-    static counter: number = 0;
-
     /**
      * @type {TNodeGroup[]}
      */
diff --git a/src/node/NodeAppender.ts b/src/node/NodeAppender.ts
index 137583a6..b5abe4a6 100644
--- a/src/node/NodeAppender.ts
+++ b/src/node/NodeAppender.ts
@@ -170,7 +170,7 @@ export class NodeAppender {
      * @returns {boolean}
      */
     private static validateBodyStatements (nodeBodyStatements: TStatement[]): boolean {
-        return nodeBodyStatements.every(statementNode => {
+        return nodeBodyStatements.every((statementNode: TStatement) => {
             return !!statementNode && statementNode.hasOwnProperty('type');
         });
     }
diff --git a/src/node/NodeUtils.ts b/src/node/NodeUtils.ts
index 7e57863c..6996df93 100644
--- a/src/node/NodeUtils.ts
+++ b/src/node/NodeUtils.ts
@@ -115,7 +115,7 @@ export class NodeUtils {
                         value = node;
                     } else {
                         value = Node.getProgramNode(<TStatement[]>[node]);
-                        value['parentNode'] = value;
+                        value.parentNode = value;
                     }
 
                     isRootNode = false;
@@ -123,8 +123,8 @@ export class NodeUtils {
                     value = parentNode || node;
                 }
 
-                node['parentNode'] = value;
-                node['obfuscated'] = false;
+                node.parentNode = value;
+                node.obfuscated = false;
             }
         });
     }