diff --git a/packages/encoder/encoder.test.ts b/packages/encoder/encoder.test.ts
index a672e9c..b2f40fd 100644
--- a/packages/encoder/encoder.test.ts
+++ b/packages/encoder/encoder.test.ts
@@ -1,3 +1,5 @@
+/* eslint-disable no-secrets/no-secrets */
+/* eslint-disable max-len */
 import { encode, decode } from './encoder';
 
 describe('encoder', () => {
@@ -43,8 +45,19 @@ describe('encoder', () => {
 
     it('nested', () => {
       expect(
-        encode({ num: 123, obj1: { obj2: { str: 'my_str' } } }),
-      ).toStrictEqual("❴'num':'∓123','obj1':❴'obj2':❴'str':'my_str'❵❵❵");
+        encode({
+          num: 123,
+          num2: 3.14,
+          b1: true,
+          b2: false,
+          str: 'test string',
+          n: null,
+          und: undefined,
+          obj1: { obj2: { str: 'my_str' } },
+        }),
+      ).toStrictEqual(
+        "❴'num':'∓123','num2':'∓3.14','b1':'🗵true','b2':'🗵false','str':'test%20string','n':'∙null','und':'∙undefined','obj1':❴'obj2':❴'str':'my_str'❵❵❵",
+      );
     });
   });
 
@@ -143,16 +156,16 @@ describe('real life example', () => {
   const encoded =
     "❴'emails':❴'sha1':⦋'f37224933f5e906904ef1f9aeca3486941664555','8a3c1b25c63e3a402e5e3a8e981054ddfec20a18'⦌,'sha256':⦋'9d67f9cab3b2775dbe38e9f6521c23d20037391c0879e4700fea9e9a7672a79e','65c4bbea793b0ac3d5adb86beac555294df2aac05c932374d1d2e382bfd3ea4c'⦌❵,'client':❴'deviceType':'Personal%20computer','browserLanguage':'en-GB','isUserLoggedIn':'🗵true','countryCode':'ge','isInternalRequest':'🗵false'❵,'id':❴'dmp':'AT56sgZZhNi6E_vvdRIAFf-HXftr%26v%3D2'❵,'numb1':'∓100500','numb2':'∓100.12345','compliance':❴'isCCPAOptIn':'🗵true','isLinkedInEmployee':'🗵false','isFunctionalOptIn':'🗵true','isGeoOptIn':'🗵true','isGDPROptIn':'🗵true','isAdvertisingOptIn':'🗵true','isAnalyticsAndResearchOptIn':'🗵true'❵,'primaryEmail':❴'sha1':'f37224933f5e906904ef1f9aeca3486941664555','sha256':'9d67f9cab3b2775dbe38e9f6521c23d20037391c0879e4700fea9e9a7672a79e'❵,'preference':❴'language':'en-us'❵❵";
   it('encode', () => {
-    let a1 = performance.now();
+    const a1 = performance.now();
     const result = encode(bigObj);
-    let a2 = performance.now();
+    const a2 = performance.now();
     console.log('encode time', a2 - a1 + ' milliseconds');
     expect(result).toEqual(encoded);
   });
   it('decode', () => {
-    let a1 = performance.now();
+    const a1 = performance.now();
     const result = decode(encoded);
-    let a2 = performance.now();
+    const a2 = performance.now();
     expect(result).toStrictEqual(bigObj);
     console.log('decode time ', a2 - a1 + ' milliseconds');
   });
diff --git a/packages/encoder/encoder.ts b/packages/encoder/encoder.ts
index cdfb122..2a069a8 100644
--- a/packages/encoder/encoder.ts
+++ b/packages/encoder/encoder.ts
@@ -57,6 +57,7 @@ const parseJSON = (str: string) => {
 
   try {
     result = JSON.parse(str, reviver);
+    // eslint-disable-next-line no-empty
   } catch {}
 
   return result;
diff --git a/rollup.config.js b/rollup.config.js
index ef2bf31..997e17a 100644
--- a/rollup.config.js
+++ b/rollup.config.js
@@ -31,7 +31,7 @@ const plugins = [
   commonjs(),
 
   !isProduction && sourcemaps(),
-  isProduction && terser(),
+  isProduction && terser({ ecma: '2020' }),
   filesize(),
 ].filter(Boolean);