diff --git a/nodejs/src/monte.ts b/nodejs/src/monte.ts
index d1ea578..2bb30b1 100644
--- a/nodejs/src/monte.ts
+++ b/nodejs/src/monte.ts
@@ -27,8 +27,8 @@ export class MonteSocket extends Duplex {
   #pending: EventEmitter = new EventEmitter();
   #counter: number = 0;
 
-  #readNonce: bigint = 0n;
-  #writeNonce: bigint = 0n;
+  #readNonce: bigint = BigInt(0);
+  #writeNonce: bigint = BigInt(0);
 
   #sock: net.Socket;
   #secret: Uint8Array;
@@ -122,7 +122,7 @@ export class MonteSocket extends Duplex {
   public encrypt(buf: Buffer): Buffer {
     const nonce = Buffer.alloc(12);
     nonce.writeBigUInt64BE(this.#writeNonce);
-    this.#writeNonce += 1n;
+    this.#writeNonce++;
 
     const cipher = crypto.createCipheriv("aes-256-gcm", this.#secret, nonce, {
       authTagLength: 16,
@@ -138,7 +138,7 @@ export class MonteSocket extends Duplex {
 
     const nonce = Buffer.alloc(12);
     nonce.writeBigUInt64BE(this.#readNonce);
-    this.#readNonce += 1n;
+    this.#readNonce++;
 
     const decipher = crypto.createDecipheriv(
       "aes-256-gcm",
diff --git a/nodejs/tsconfig.json b/nodejs/tsconfig.json
index 290c877..55fa89d 100644
--- a/nodejs/tsconfig.json
+++ b/nodejs/tsconfig.json
@@ -5,7 +5,7 @@
     /* Basic Options */
     //    "incremental": true,
     /* Enable incremental compilation */
-    "target": "es2020",
+    "target": "es2015",
     /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019', 'ES2020', or 'ESNEXT'. */
     "module": "commonjs",
     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', 'es2020', or 'ESNext'. */