Lead Full-Stack Developer – Autonomous AI & Live Commerce Ecosystem (Serbia)

Job Title: Lead Full-Stack Developer – Autonomous AI & Live Commerce Ecosystem (Serbian Market) Project Overview We are seeking an expert Full-Stack Developer or a small specialized team to build a next-generation marketplace platform tailored for the Serbian market. The project is fully architected with a detailed technical brief ready for implementation. The core value proposition is a "Zero-Input" user experience driven by autonomous AI agents and integrated Live Commerce. Technical Stack • Frontend: FlutterFlow (Native Flutter/Dart export capability required).  • Backend: Firebase Blaze Plan (Firestore, Auth, Cloud Functions).  • AI Engine: OpenAI GPT-4o-mini (Vision & NLP) + Pinecone (Semantic/Vector Search).  • Video: [login to view URL] (Ultra-low latency broadcast streaming).  • Automation: Firebase Cloud Functions orchestrated via Node.js.  Key Modules for Implementation 1. Autonomous AI Agent System: • Development of three specialized agents (Marketing, Sales, and Logistics) that utilize Firestore state documents to act autonomously.  • Agents must handle automated listing optimization, real-time sales negotiations (within set discount bounds), and logistics mapping.  2. Dynamic Enterprise Admin Dashboard: • A comprehensive interface allowing the owner to modify B2B subscription tiers (e.g., €100/mo), B2C token pricing, commission rates, and logistics fees in real-time without code changes.  3. Serbian Fintech & Compliance Integration: • Implementation of NBS IPS QR codes via official REST API.  • Card processing integration via CorvusPay.  • Automated e-fiscalization through third-party ESIR providers (e.g., Teron or NetRačuni).  4. Multi-Logistics Hub: • Direct integration with PostExpress (Pošta Srbije) REST API for manifests, tracking, and shipping calculations.  • Webhook support for secondary couriers (BEX).  5. B2B SaaS Features: • Bulk AI-powered inventory upload (handling 1,000+ items) via GPT-4o-mini Vision.  • Advanced sales and conversion analytics for business accounts.  Budget & Security Requirements • Operational Safety: Implementation of a multi-tiered "Kill-switch" system with Firestore circuit breakers to prevent runaway API costs.  • Future-Proofing: Architecture must be "Escrow-ready" to transition from direct payments to bank-intermediated escrow (e.g., OTP Banka) without core logic refactoring.  • Confidentiality: A full Technical Brief (Firestore schemas, Cloud Function signatures, etc.) will be provided only after a signed NDA.  Project Timeline & Budget • Fixed Budget: €1,300. • Timeline: 21 days (delivered in three 7-day sprints: Core, Fintech, Live).  Interview Questions (Required for applicants): 1. How will you implement the NBS IPS QR generation to ensure it strictly follows the Serbian pipe-delimited text standard?.  2. What is your strategy for optimizing OpenAI Vision API calls for a bulk upload of 1,000+ images while keeping costs under $1.00?.  3. How will you handle the automated fiscal receipt generation immediately following a successful CorvusPay transaction confirmation?.

Project ID: 40252993