Social features power many successful apps - Twitter, Instagram, Facebook, LinkedIn. Learning how to build feeds, interactions, and social graphs makes you more valuable as a developer.
This project teaches complex database relationships. A post belongs to a user, has many likes and comments, and comments can have replies. Managing these relationships properly is essential for building scalable applications.
You'll learn optimistic UI updates, which make apps feel fast and responsive. When a user clicks like, the heart fills immediately without waiting for the server. This technique dramatically improves user experience.
Social features are in many apps, not just social media. Understanding how to build feeds, likes, comments, and follows teaches you about complex data relationships and user interactions.
This project introduces optimistic updates - making the UI respond instantly before the server confirms. This makes apps feel fast and responsive, which users love.
You'll learn how to build algorithms for content feeds, handle nested data like comments with replies, and work with many-to-many relationships like follows. These patterns appear in forums, review systems, and collaborative platforms.
Create a social media platform similar to Twitter or Instagram with posts, comments, likes, and a follow system. This project introduces complex data relationships, optimistic UI updates, and algorithms for content personalization.
You'll work with multiple interconnected data models, implement sophisticated queries, and build an engaging user interface that feels responsive and modern.
Design and implement complex database relationships
Build feed algorithms that sort and filter content
Implement optimistic UI updates for better UX
Handle nested data structures (posts with comments)
Create efficient queries with population and aggregation
Build infinite scroll pagination
User profiles with bio, avatar, and follower counts
Create, edit, and delete posts (text and image)
Like and unlike posts with like count display
Comment on posts with nested replies
Follow and unfollow other users
Home feed showing posts from followed users
Explore feed showing popular posts from all users
User profile page with their posts and stats
Infinite scroll loading for feeds
Real-time like counts and comment counts
User: id, username, email, bio, avatarUrl, followers[], following[], createdAt
Post: id, userId, content, imageUrl, likes[], commentCount, createdAt
Comment: id, postId, userId, content, parentCommentId, likes[], createdAt
Follow: followerId, followingId, createdAt
POST /api/posts - Create new post
GET /api/posts/feed - Get personalized feed (following users)
GET /api/posts/explore - Get explore feed (popular posts)
GET /api/posts/:id - Get single post with comments
PUT /api/posts/:id - Edit post
DELETE /api/posts/:id - Delete post
POST /api/posts/:id/like - Like a post
DELETE /api/posts/:id/like - Unlike a post
POST /api/posts/:id/comments - Add comment to post
GET /api/posts/:id/comments - Get post comments
POST /api/users/:id/follow - Follow a user
DELETE /api/users/:id/follow - Unfollow a user
GET /api/users/:id/profile - Get user profile and posts
Home feed: Show posts from users you follow, sorted by recency
Explore feed: Show posts from all users, sorted by popularity score
Popularity score calculation: (likes * 2) + comments - (hours since posted)
Pagination: Load 20 posts at a time with cursor-based pagination
Cache feed results for 5 minutes to reduce database load
Navigation bar with home, explore, profile, and create post buttons
Post creation modal or page with text input and image upload
Post cards showing user info, content, image, and interaction buttons
Like button that updates immediately (optimistic update)
Comment section that expands to show all comments
User profile showing follower count, following count, and posts grid
Follow/unfollow button with optimistic updates
Infinite scroll that loads more posts as user scrolls down
Pull-to-refresh on mobile
Empty states for feeds with no content
Implement optimistic updates for likes and follows (update UI before server confirms)
Handle optimistic update rollbacks if server request fails
Build efficient queries using MongoDB aggregation for feed generation
Implement cursor-based pagination for infinite scroll
Normalize data to avoid showing stale user info in posts
Handle race conditions when multiple users interact with same post
Cache feed data appropriately to reduce server load
Implement intersection observer for infinite scroll trigger
Liking: Add userId to post.likes array, increment like count
Commenting: Create new comment document, increment post.commentCount
Following: Create follow relationship, update follower/following counts
Show "You liked this" indicator on liked posts
Show "Following" badge on followed users
Disable actions while request is pending
Add hashtag support with clickable tags
Implement user mentions with @ symbol
Add post sharing/reposting functionality
Create notification system for likes, comments, follows
Add direct messaging between users
Implement post bookmarking/saving
Add image filters or cropping before upload
Show "suggested users to follow" based on mutual connections
MongoDB Aggregation: MongoDB docs on aggregation pipeline. It's powerful for complex queries.
Optimistic UI: Search for "optimistic UI updates React" to learn the pattern.
Infinite Scroll: Look up "Intersection Observer API" for smooth infinite scrolling.
Data Relationships: Search for "MongoDB one-to-many" and "many-to-many" patterns.
Cursor Pagination: Learn why cursor-based pagination is better than offset for large datasets.
Feed Algorithms: Read about "social media feed algorithms" to understand ranking.
MongoDB Relationships: Search for "MongoDB relationships" or "Mongoose populate". Learn how to connect different data models.
Aggregation Pipeline: MongoDB aggregation docs. Aggregation helps you build complex queries for feeds.
Optimistic Updates: Search for "React optimistic updates" or "optimistic UI pattern".
Infinite Scroll: Look up "Intersection Observer API" or "React infinite scroll tutorial".
Cursor Pagination: Search for "cursor-based pagination vs offset pagination". Cursor is better for feeds.
Feed loads quickly and shows relevant content
All interactions feel instant due to optimistic updates
Infinite scroll works smoothly without lag
Like and follow counts are accurate across all views
Comments appear in correct order (newest or oldest first)
User profile accurately reflects their activity
Application handles edge cases (unliking, unfollowing)
No duplicate posts appear in feed
Study MongoDB aggregation pipeline for complex queries
Research cursor-based pagination vs offset pagination
Learn about optimistic UI updates in React
Explore Intersection Observer API for infinite scroll
Look into data denormalization strategies
Hint: When implementing optimistic updates, always store the previous state before making changes. If the server request fails, you can roll back to the previous state and show an error message.
For the feed algorithm, create database indexes on fields you'll query frequently (userId, createdAt, likes count). This will significantly speed up feed generation as your database grows.
Submit Your Project
Once you've completed this project, submit your GitHub repository link below: