Build a HEX color guessing game for designers. 

Color Codes Game

Train your array algorithm skills by building an interactive transfer list component!

Transfer list

Build a real-life star rating component ready to use for your next project!

Star rating

Build a real-life modal component and learn React Portals along the way!

Modal Portal

Level up your array skills by building sorting and searching-enabled table component!

Data table

Build a cached paginating list of crypto currencies from an API

Paginating Cryptocurrencies

Display weather conditions by building a Weather forecasting component driven by an API.

Weather forecast

Level up your CSS abilities and create a reusable popover component ready to use for your next project!

Popover Component

Transform a malformed component into a production ready one.

Validate Markup

Build a custom input component to receive and properly format phone numbers.

Phone Number Input

Test your recursion skills by building an indeterminate checkbox tree.

Indeterminate checkboxes

Use Array.map to transform arrays of data as the problems get harder as you progress. 

Map I

Navigate through 3 operations exercises which get harder as you move along.

Operations Challenge

Complete the 4 problems in this set by only making use of built-in Javascript Array methods.

Array Builtins I

Build a react dropdown menu component that displays the top trending Cryptocurrency assets from an external API we provide to you.

Trending Cryptos Dropdown Component

Build a custom hook which returns if the user has been active within the given timeout.

Track Idle States

Create a custom hook called `useToggle` which flips the value of a boolean.

Toggle Between States

Build Tic-Tac-Toe, one of the most asked Interview questions for frontend engineers!

Tic Tac Toe 

Write a function that returns a new function that can be invoked at most once per wait time. 

Throttle

Given a string, return a new string with the reversed order of characters in the original string.

String Reversal w/ Builtins

Write a function that takes an object and returns a new object with the keys and values sorted.

Sort Object

Write a function that accepts an object and the sort order and returns a list of the keys of the object sorted using the sort order

Sort an Objects Keys

Write a function to rotate an array of n elements to the left by k steps.

Rotate Array

A common junior engineer or weeding question - reverse the words in a given string.

Reverse Words in a String

Test your reduce skills by using array.prototype.reduce to solve a few problems of medium difficulty.

Reduce II

Test your Array.reduce skills by implementing a few basic array functions.

Reduce I

Implement a useful utility method for aggregating the results of multiple promises.

Promise.prototype.all

Practice building queues by creating a list of loading indicators.

Progress indicators

Implement a hook that allows you to poll a server endpoint at various intervals.

Poll for Data

Practice your CSS skills with this real-life video task!

Video to Bottom Corner

Create a wrapper around the HTML5 audio tag in the form of a custom hook!

Play Audio Files

Build pickBy, a function that is used to select properties from an object.

Pick By Property

Write a function which omits properties from a source object based on the properties of another.

Omit Properties from Object

Write a function that takes an object and flattens it to a single level using dot notation.

Object to Dot Notation String

Develop a responsive masonry layout container. 

Masonry Layout for Photos

Put your array mapping skills to the test with 3 exercises of medium difficulty.

Map II

Write a function that converts a given object into an array of arrays.

Make Pairs

Create a responsive navigation bar with a full screen mobile hamburger menu.

Responsive Navigation

Create a reusable hook that can be used to store and retrieve data from localStorage. 

Local State Management

Build a frontend brain teaser style game consisting of a grid of squares that light up.  

Light Up Squares

Follow along with a video tutorial to buid Tic-Tac-Toe as you learn the basics of React

Learn React Basics with Tic-Tac-Toe

Learn about one of the most elusive frontend interview questions, currying!

Javascript Currying

Write a function to determine if a given set of strings are isomorphic.

Isomorphic Strings

Test your Javascript object manipulation skills by inverting objects

Invert a JS Object

Create a reusable debounce function, a tricky but highly useful technique in frontend development.

Implement Reusable Debounce

Display a carousel of images, one at a time, and allow the user to navigate between them

Image Carousel

Create a custom hook that will add an event listener to an element and remove it when the component unmounts.

Hook into Events

Get hands-on with CSS Grid by creating a practical fly-out menu project!

Flyout menu

Implement Array.prototype.flat from the latest Javascript standard 

Flatten Array

Implement a pattern for managing communication between different parts of an application through the use of events and subscriptions.

Event Emitter

Find elements in the DOM by a given style.

Elements By Style

Create a custom hook to handle timeouts and delay the execution of a given function.

Delay Execution by Timeout

Build a custom hook that logs the name of the component and its props to the console during the component's lifecycle.

Debug Utility Logger

Build a custom hook that allows for infinite scrolling of a list of cryptos!

Crypto Infinite Scroll

Create a full-fledged autocomplete search bar for crypto currencies

Crypto Autocomplete Search

Build the Array.prototype.map method from the latest ES6 standard.

Array.prototype.map

Can you complete all of these medium difficulty exercises just using Array.prototype builtin methods?

Pick your adventure

Interview Projects & Problems

Interview Quizzes

Javascript Mastery

Practice with projects & problems taken from real interviews. Each with a set of unit tests so you never miss an edge case and solution explanations written by senior engineers to guide you.