15 questions · 15 minutes · instant score

Walk into the interview already practised.

Pick your stack and level. You get timed questions, an explanation for every answer, and the topics to practise next.

JavaScript

closures, the event loop, prototypes, async/await, ES modules

3 of 3 levels ready

TypeScript

types vs interfaces, generics, narrowing, utility types

3 of 3 levels ready

React

hooks, rendering, state management, performance, Server Components

3 of 3 levels ready

Next.js

App Router, caching, server actions, rendering strategies

3 of 3 levels ready

Node.js

event loop, streams, Express, error handling, scaling

3 of 3 levels ready

Python

data structures, generators, decorators, typing, async

3 of 3 levels ready

Django

ORM, middleware, views, migrations, security

3 of 3 levels ready

Java

collections, concurrency, JVM, Spring basics

3 of 3 levels ready

Go

goroutines, channels, interfaces, error handling

3 of 3 levels ready

C# / .NET

LINQ, async, dependency injection, ASP.NET Core

2 of 3 levels ready

PHP / Laravel

Eloquent, routing, queues, security

3 of 3 levels ready

SQL

joins, indexes, transactions, window functions, query plans

3 of 3 levels ready

System Design

scaling, caching, queues, consistency, trade-offs

3 of 3 levels ready

DevOps

Docker, Kubernetes, CI/CD, observability, Linux

3 of 3 levels ready

AWS

EC2, S3, IAM, Lambda, VPC, cost and reliability

3 of 3 levels ready

Data Science

statistics, pandas, ML fundamentals, evaluation

3 of 3 levels ready

Machine Learning

models, training, overfitting, metrics, LLMs

2 of 3 levels ready

Android

Kotlin, lifecycle, Jetpack Compose, coroutines

3 of 3 levels ready

iOS

Swift, SwiftUI, concurrency, memory management

2 of 3 levels ready

QA & Testing

test design, automation, Playwright/Selenium, API testing

1 of 3 levels ready