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Certificates

Certificate for JavaScript Memory and Garbage Collection

JavaScript Memory and Garbage Collection

Issued 6 October 2026

Implement listenTo function

1,431

Company Structure Validator

1,794

Compare Semantic Versions

1,304

Implement a Timeout-Based API Wrapper with Optional Retry

2,862

Measure Function Execution Time

1,991

Breadcrumb Chain Problem

3,409

Build an API Client

3,270

Function Call Counter

2,828

Count Total Comments

4,046

String Compression and Decompression

4,066

Implement Event-Driven Key-Value Store

2,755

Implement Promisify Polyfill

2,851

How to create analytics SDK in JavaScript?

6,920

How to group array of objects by key?

7,378

How to implement custom Array.prototype.square method?

5,619

Build a Virtual DOM to actual HTML DOM Convertor | DOM Renderer

6,775

How to implement a chainable Add function to calculate the sum of numbers?

7,423

How to implement Array.isArray? JavaScript Interview Question | Array Polyfills

7,624

How to implement Array.prototype.filter? JavaScript Interview Question | Array Polyfills

5,941

How to implement an Asynchronous Task Runner with Concurrency Control? Rippling Frontend Interview Question

7,585

How to implement auto-retry Promise on Rejection? | Frontend Problem Sovling

6,799

How to implement a prize calculator? JavaScript Interview Question

4,790

Implement Count By | JavaScript Problem Solving

3,603

How to implement feature flag functionality? Atlassian Frontend Interview Question

10,761

Implement a Credit Card Masker | Klarna Frontend Interview Question | JavaScript

6,854

Write a function to return the count of numbers in an Array | MakeMyTrip Frontend Interview Question

6,565

How to implement a function to convert a string input into an object? | Razorpay Interview Question | JavaScript

7,681

How to find the most frequent word in a paragraph? Frontend Problem Solving | JavaScript

5,605

Implement a function that returns the number of parameters expected by a function in JavaScript

5,149

How to implement pipe utility? | Razorpay Interview Question | JavaScript

6,588