Tools: Building GigFlow: A Real-Time Freelance Marketplace with Secure Hiring Logic

Demo Video: ## 🚀 What is GigFlow? ## 🧱 Tech Stack ## Frontend ## Backend ## Deployment ## 🔐 Authentication (JWT + HttpOnly Cookies) ## 📦 Core Data Models ## 🧠 The Hiring Problem (The Hard Part) ## 🔒 Solving Race Conditions with MongoDB Transactions ## High-level flow: ## ⚡ Real-Time Updates with Socket.io ## 🖥️ Frontend Flow ## Client ## Freelancer ## 🌍 Deployment Lessons ## Backend (Render) ## Frontend (Vercel) ## 🧪 What This Project Demonstrates ## 🔗 Links ## 🧠 Final Thoughts Modern marketplaces aren’t just about CRUD APIs — they’re about correctness, trust, and real-time feedback. In this post, I’ll walk through how I built GigFlow, a full-stack freelance marketplace where clients can post jobs, freelancers can bid, and hiring happens atomically and in real time. This project focuses heavily on: GigFlow is a mini freelance marketplace where: The core challenge wasn’t the UI — it was ensuring data integrity and correctness under concurrency. Authentication is handled using JWT stored in HttpOnly cookies, which: This enables role-less design — users can act as both client and freelancer without separate accounts. The most important rule: Only one freelancer can be hired for a gig — ever. This is where many systems fail. The hire logic is wrapped inside a MongoDB session + transaction. If any step fails, everything rolls back. Once a freelancer is hired: No polling. No refresh. Instant feedback. State is kept minimal and predictable using Context API. This is not a “todo app” — it’s a system designed to behave correctly under pressure. The hardest part of full-stack development isn’t writing code — it’s making sure the system behaves correctly when multiple things happen at once. GigFlow was built with that principle in mind. Templates let you quickly answer FAQs or store snippets for re-use. Are you sure you want to hide this comment? It will become hidden in your post, but will still be visible via the comment's permalink. Hide child comments as well For further actions, you may consider blocking this person and/or reporting abuse CODE_BLOCK: { name, email, password } Enter fullscreen mode Exit fullscreen mode CODE_BLOCK: { name, email, password } CODE_BLOCK: { name, email, password } CODE_BLOCK: { title, description, budget, ownerId, status: "open" | "assigned", assignedTo } Enter fullscreen mode Exit fullscreen mode CODE_BLOCK: { title, description, budget, ownerId, status: "open" | "assigned", assignedTo } CODE_BLOCK: { title, description, budget, ownerId, status: "open" | "assigned", assignedTo } CODE_BLOCK: { gigId, freelancerId, message, price, status: "pending" | "hired" | "rejected" } Enter fullscreen mode Exit fullscreen mode CODE_BLOCK: { gigId, freelancerId, message, price, status: "pending" | "hired" | "rejected" } CODE_BLOCK: { gigId, freelancerId, message, price, status: "pending" | "hired" | "rejected" } - Secure authentication - Correct hiring logic - Preventing race conditions - Real-time updates using Socket.io - Any authenticated user can post a gig (client role) - Any user can bid on gigs (freelancer role) - A client can hire exactly one freelancer per gig - All other bids are automatically rejected - The hired freelancer gets a real-time notification - React (Vite) - Tailwind CSS - Context API for state management - Socket.io Client - Fetch API with credentials - Node.js + Express - MongoDB + Mongoose - JWT Authentication (HttpOnly cookies) - MongoDB Transactions - Frontend: Vercel - Backend: Render - Database: MongoDB Atlas - Prevents access from JavaScript (XSS-safe) - Works cleanly with credentials: "include" - Verifies the JWT - Attaches the authenticated user to req.user - Two clients (or two tabs) click Hire at the same time - Without protection, two bids could be marked as hired - Start a session - Check if the gig is still open - Update gig → assigned - Mark selected bid → hired - Mark all other bids → rejected - Commit transaction - Exactly one hired freelancer - No partial or inconsistent state - The backend emits a hired event to that freelancer’s socket room - The freelancer’s dashboard updates instantly - Gig becomes assigned - Submit bids - Track bid status - Receive real-time hire notification - Environment variables must be explicitly set - CORS must allow the deployed frontend domain - Socket.io needs the same CORS config as Express - API base URL must point to deployed backend - Fetch requests must include credentials - Correct API design - Secure authentication - Transactional integrity - Real-time communication - Production deployment awareness - Live App: https://account-manager-vite.vercel.app/ - GitHub Repo: https://github.com/Sufalthakre18/gigflow-fullstack-marketplace - Home page :