Website (Full Stack Developer)

Posted last week

Only freelancers located in the U.S. may apply.U.S. located freelancers only

Summary

We are seeking an elite, senior-level Full-Stack Developerto engineer a high-velocity, real-time horse racing web platform from the ground up. The core application loop revolves around a fast-paced snake draft for individual horse races, complete with an integrated, synchronized sub-second live video stream of the race. Following official track results, the platform automatically executes structured financial payouts to users using Venmo/PayPal Payout rails. The entire tech stack must be built utilizing a unified all-JavaScript environment (MERN stack) optimized to eliminate database race conditions and handle volatile real-time traffic spikes. Core Key Milestones & Project Deliverables: Milestone 1: Backend Infrastructure & User Security (15%) Set up a Node.js/Express.js application environment and establish a scalable MongoDB Atlas architecture. Implement user registration, secure JWT/bcrypt authentication, profile management, and verified phone-number registration and/or email registration. Milestone 2: Sports Data Ingestion & Automation (25%) Establish integration with a third-party commercial horse racing API (e.g., Equibase or Sportradar). Build persistent background workers (using BullMQ, Redis, or Node-Cron) to automatically ingest daily race cards, scratches, gate changes, and final official race metrics. Milestone 3: Real-Time Draft & WebRTC Video Integration (40%) Develop an interactive React.js draft dashboard utilizing Socket.io for live, synchronized state management. Implement our custom mathematical snake draft logic featuring a strict 20-second user-pick countdown timer. Build server-side automatic timeout handlers to auto-assign choices if a user disconnects or freezes. Embed an ultra-low latency HTML5 video canvas layer leveraging WebRTC (via WHIP/WHEP protocols) to ingest an RTMP stream from a media server (e.g., Ant Media or Wowza) ensuring sub-500ms video playback. Milestone 4: Venmo Payout Integration & Compliance Guardrails (20%) Seamlessly integrate the official PayPal/Venmo Payouts API to programmatically distribute money from our platform wallet directly to users' accounts and/or phone numbers. This can be worked around using a p2p format, if necessary due to compliance and regulation. Code a reliable system ledger that deducts a custom platform percentage rake prior to finalizing winner distributions. Implement an IP geo-fencing gateway (such as MaxMind GeoIP2) to block real-money contest entry from illegal jurisdictions. Technical Stack Requirements: Frontend: React.js (Next.js preferred), Tailwind CSS, Socket.io-client. Backend: Node.js, Express.js, Socket.io, Node-Cron or BullMQ.Database & Memory: MongoDB (Mongoose), Redis (for lightning-fast leaderboard and timer caching). Streaming Protocols: WebRTC, WHIP/WHEP, RTMP stream handling. Integrations: PayPal/Venmo Payouts SDK, REST/JSON Sports Data APIs, GeoIP lookup utilities. Strict Operational Code Quality Terms: 1. Repository Ownership: All codebase code and architectural modules must be pushed to our private company GitHub repository at least three times a week. Milestone releases will only be approved after clean local compilation and inspection. 2. IP Assignment: By applying for and accepting this position, you acknowledge that 100% of the developed application logic, system schemas, and code components represent a dedicated Work-for-Hire owned exclusively by the client. 3. ACID Database Transactions: You must guarantee and demonstrate via unit testing that the MongoDB schema handles marketplace swaps and concurrent drafting selections via absolute ACID Transaction Sessions to totally prevent double-spend or double-draft race conditions. To Apply, Please Answer the Following 3 Screening Questions: 1. How do you plan to structure the server environment and React architecture to keep a 30-second live countdown timer perfectly synced down to the millisecond for 4 or more different players concurrently browsing via WebSockets? 2. Please share a summary or a live link of a project you built from scratch that handled live WebRTC ultra-low-latency video delivery or complex stream handshakes. 3. What is your specific experience with financial ledger architectures? Explain how you intend to protect the MongoDB operations against multi-user transactional conflicts.

  • $15,000.00

    Fixed-price
  • Expert
    Experience Level
  • Remote Job
  • Complex project
    Project Type
Skills and Expertise
Mandatory skills
Next.js
Tailwind CSS
Socket.io
Activity on this job
  • Proposals:20 to 50
  • Last viewed by client:5 days ago
  • Interviewing:
    0
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Jun 24, 2026
  • United States
    12:21 PM

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