DevTinder — Backend

A production-deployed REST + real-time API powering DevTinder, a Tinder-style networking platform built for developers to discover, connect, and chat with each other based on real skills — with AI-flavored matching, payments, moderation, and growth mechanics layered on top of the base course project.

🔗 Live App: http://3.26.26.82 🔗 Frontend Repo: DevTinder-Frontend

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Screenshots

Add screenshots below as you take them. Recommended shots for the backend README specifically (things that show architecture and behavior, not just UI):

• Terminal output showing a successful cron job run (the "Sending reminder emails to N users" log line)
• MongoDB Compass view of a User document showing the github, isPremium, and referralCode fields populated
• Postman/Thunder Client screenshot hitting /user/feed and showing the matchScore field in the JSON response
• Razorpay Dashboard screenshot showing a successful test webhook delivery
• A simple architecture diagram (Nginx → Express → MongoDB/Socket.io/Razorpay/GitHub OAuth) — even a hand-drawn one photographed works

![Cron job digest email running](./screenshots/cron-job-log.png)
![Feed API response with match scores](./screenshots/feed-match-score.png)
![Razorpay webhook delivery log](./screenshots/webhook-delivery.png)

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What This Is

Most "Tinder clone" tutorial projects stop at authentication and a swipe feed. This one goes considerably further — a fully deployed backend handling GitHub-verified developer identity, skill-based match scoring, real payments with webhook verification, live chat with content moderation, and referral-driven growth mechanics, all running on a self-managed AWS EC2 instance behind Nginx.

Built on top of the Namaste Node.js course architecture, then extended well beyond its curriculum with production-grade fixes, security hardening, and five additional features designed around real product and monetization thinking.

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Features

Core Platform

• JWT-based authentication with HTTP-only cookies (signup, login, logout)
• Profile management (bio, skills, photo, age, gender)
• Developer discovery feed with connection request flow (interested / ignored)
• Connection request review (accept / reject)
• Connections & pending requests management

Developer Identity Verification

• GitHub OAuth 2.0 integration with CSRF-protected state validation
• Pulls real public repo count and top languages directly from the GitHub API
• Verified badge surfaced across Feed, Requests, and Connections

Skill-Based Matching & Icebreakers

• Jaccard similarity scoring between users' skill sets, computed live (no external AI API, no cost)
• Feed results ranked by match quality, not just recency
• Template-based icebreaker generation referencing genuinely shared skills

Trust, Safety & Moderation

• User-to-user reporting system with categorized reasons
• Admin-only review dashboard (role-gated via a dedicated adminAuth middleware)
• Real-time chat message filtering against a banned-word list before messages are ever persisted

Monetization

• Razorpay-powered Premium membership, now actually granting isPremium status on both client-side verification and webhook confirmation (the webhook is treated as the authoritative source of truth)
• "Boost" mechanic — temporarily surfaces a premium user's profile at the top of every feed
• Profile view analytics (7-day / 30-day / all-time), logged automatically as users appear in others' feeds

Growth & Engagement

• Unique referral links; both parties receive 7 days of Premium when a referral is applied
• Real-time Socket.io notification to the referrer the moment their link is used
• Gamified connection-count badges (First Connection → DevTinder Legend), computed live

Email & Automation

• Transactional email via AWS SES on new connection requests
• Daily cron digest (node-cron) summarizing the previous day's requests, now including a weekly growth line

Real-Time Chat

• Socket.io-powered live messaging, authenticated at the handshake level via JWT (never trusting client-claimed identity)
• Server-side enforcement: messages only flow between users with an accepted connection
• Persistent history with per-user "last seen" tracking for accurate unread counts

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Tech Stack

Layer	Technology
Runtime	Node.js, Express
Database	MongoDB, Mongoose
Auth	JWT, bcrypt, HTTP-only cookies, GitHub OAuth 2.0
Real-time	Socket.io
Email	AWS SES (@aws-sdk/client-ses)
Payments	Razorpay
Scheduling	node-cron, date-fns
Deployment	AWS EC2, Nginx (reverse proxy), PM2 (process manager)

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Architecture Notes

• Nginx routes /api/* to the Express server and /socket.io/* separately with WebSocket upgrade headers, while serving the built React frontend as static files at /.
• Razorpay webhooks are verified against the raw, unparsed request body, since signature validation fails silently on an already-JSON-parsed body.
• Socket connections are authenticated at the handshake level by decoding the JWT from the cookie header — client-sent user IDs are never trusted for identity, only for addressing which room to join.
• Skill matching uses Jaccard similarity computed in application code rather than a paid embeddings API — a deliberate cost/complexity trade-off appropriate at this project's scale, with a documented upgrade path to vector search noted in code comments.
• A shared getIO() accessor lets any route emit real-time events (e.g. referral notifications) without those routes needing direct access to the HTTP server or Socket.io setup.

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API Overview

Method	Route	Description
POST	/signup	Register a new user
POST	/login	Authenticate and receive JWT cookie
POST	/logout	Clear auth cookie
GET	/profile	Get logged-in user's profile
PATCH	/profile/edit	Update profile fields
GET	/user/feed	Get discoverable, match-ranked user feed
GET	/user/connections	List accepted connections, with match scores
GET	/user/requests/received	List pending incoming requests, with match scores
GET	/user/badges	Get gamification badge progress
POST	/request/send/:status/:toUserId	Send a connection request (interested/ignored)
POST	/request/review/:status/:requestId	Accept/reject a received request
GET	/auth/github	Start GitHub OAuth flow
GET	/auth/github/callback	GitHub OAuth callback handler
GET	/matching/icebreaker/:targetUserId	Generate a skill-based icebreaker
POST	/report/:targetUserId	Report a user
GET	/admin/reports	(Admin only) List pending reports
PATCH	/admin/reports/:reportId	(Admin only) Update a report's status
POST	/payment/create	Create a Razorpay order
POST	/payment/verify	Verify payment signature, grant Premium
POST	/payment/webhook	Razorpay webhook receiver
POST	/premium/boost	(Premium only) Activate a 24-hour feed boost
GET	/premium/analytics	(Premium only) Get profile view stats
GET	/referral/my-link	Get/generate the user's referral link
POST	/referral/apply	Apply a referral code on signup
GET	/chat/:targetUserId	Fetch chat history with a user
GET	/chats	List all conversations with previews & unread counts

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Getting Started Locally

git clone https://github.com/Anu1606-dev/DevTinder-Backend.git
cd DevTinder-Backend
npm install

Create a .env file (see .env.example for the full list — never commit real values):

PORT=7777
CLIENT_URL=http://localhost:5173
MONGO_URI=
JWT_SECRET=
AWS_ACCESS_KEY=
AWS_SECRET_KEY=
AWS_REGION=
SES_FROM_EMAIL=
RAZORPAY_KEY_ID=
RAZORPAY_KEY_SECRET=
RAZORPAY_WEBHOOK_SECRET=
GITHUB_CLIENT_ID=
GITHUB_CLIENT_SECRET=
GITHUB_CALLBACK_URL=http://localhost:7777/auth/github/callback

Run the dev server:

npm run dev

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Roadmap

• Search by name/skill
• Vector-embedding-based semantic matching (upgrade path from current Jaccard similarity)
• Pagination for chat message history
• Presence indicators ("online now")

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Author

Anushka Sarkar GitHub · LinkedIn · X/Twitter