Daily Coding Challenges & Projects

Frontend Mini Project Challenge

HTML, CSS Grid / Flexbox, and JavaScript

Challenge :

Project : Create a Responsive Image Gallery

• Support filtering by category using buttons.
• Add lightbox view on image click.

Bonus : Persist selected category with localStorage.

Backend Challenge

Language Focus : Scala, R, Swift (Vapor), TypeScript (Node.js)

Scala Task :

Challenge : Write a Scala program to parse a JSON file of employee records and compute average salary by department.

R Task :

Challenge : Create an R script that connects to a PostgreSQL database and visualizes employee salary trends over the last year using ggplot2.

Swift (Vapor) Task Task :

Challenge :Build a simple REST API with Vapor to store and retrieve project tasks.

TypeScript (Node.js) Task :

Challenge :Create a Node.js + TypeScript Express endpoint that validates form input using zod or yup.

Database Query Challenge

Problems on SQL - HR Database :

1. Find employees with more than 5 years of experience and no promotion in the last 3 years.
2. Write a query to list each department and the number of employees in it, ordered by size

Data Structures & Algorithms Challenge

• Easy:
• Problem :Reverse an array in-place.
• Hint :Use two-pointer technique from start and end.
• Medium:
• Problem : Implement a queue using two stacks.
• Hint :Use one stack for enqueue, one for dequeue.
• Hard:
• Problem :Find the maximum of all subarrays of size k in an array.
• Hint :Consider using a deque for optimal sliding window performance.

Bug of the Day

Language Focus : Scala, R, Swift, TypeScript

TypeScript Bug

Buggy Code:

function greet(name: string | undefined) {
  console.log("Hello, " + name.toUpperCase());
}
greet(undefined);

Fix : Handle undefined safely using optional chaining or default parameter.

📋 Daily Micro-Project

Backend :

Task :

Project : Build a simple JWT-based login system in Node.js (TypeScript preferred).

• Login route returns token.
• Protected route checks token in Authorization header.

Bonus :Add token expiration logic.

Trivia: 5 Fun Facts

1. Who developed the Python programming language?
2. What was Java originally called?
3. Which company owns GitHub?
4. Which database uses the .bson file format?
5. What does the acronym API stand for?

Tool & Resource of the Day

Tool : GitLens (VS Code Extension)

Description : Supercharges Git in VS Code – shows authorship, history, and blame inline.

Resource Roundup :

• Awesome Go –curated Go resources
• Frontend Mentor –real-world frontend project challenges
• Full Stack Open –comprehensive web dev course

Interview Question of the Day

Daily Interview Questions

Frontend :
1. What is memoization in React?
2. How do you handle form validation in Vue.js?
3. What is the Shadow DOM?
4. Describe the differences between controlled and uncontrolled components.

Backend :
1. How do goroutines differ from threads in Go?
2. What are closures in JavaScript and how are they used in callbacks?
3. Describe a use case for a message queue.
4. What are some common REST API versioning strategies?

Database :
1. Explain the ACID properties of transactions.
2. What is normalization? List its types.
3. What is the purpose of a database index?

Others :
1. What’s the difference between a virtual machine and a container?
2. Explain CI/CD in the context of DevOps.

Daily Quiz Challenge

Frontend :

1. What is JSX in React?
2. Which property controls an element’s stacking order in CSS?
3. What is the key prop in React used for?

Backend :

1. What does the async keyword do in JavaScript?
2. What is the role of a schema in GraphQL?
3. Which HTTP method is typically used to update a resource?

Others :

• Which SQL clause is used to group rows that have the same values?
• Which Unix command lists files and directories?

Weekly Cross-Domain Activities ( July 25 to July 31, 2025 )

API of the Day:

Build a crypto tracker using the CoinGecko API.

Display current prices and 24h change of selected coins.

Linux/DevOps Tip :

Top 10 htop features for server monitoring (process tree, CPU graph, filter by user, etc.)

Real-World Project of the Week ( July 25 to July 31, 2025 )

Project of the Week:

Build a Task Manager App with React + Node.js + MongoDB (MERN Stack)

Collaborative Project:

Create an Open Source GitHub repo for “Interview Prep Hub” – collect user-submitted questions and answers.

Case Study:

Explore how Notion manages blocks and rich content – replicate a basic block-based note editor with contenteditable elements.