Build MVP: AI Voice & WhatsApp Sales Platform (Next.js + Vapi.ai/Retell + Meta Graph API + Supabase)

Posted 4 days ago

Worldwide

Summary

Job Description We are seeking a high-velocity Full-Stack Next.js & Voice AI Engineer to build an Minimum Viable Product (MVP) similar to Levrage.ai and Joyz.ai. The goal is to create a lightweight, unified sales & support workspace that enables businesses to run real-time AI Voice Telephony (Inbound/Outbound) and Automated WhatsApp/Instagram Chatbots, with all leads aggregated into a Unified Inbox & Lead Management Dashboard. Technical Strategy: To keep development costs and setup time low, we are NOT building voice orchestration or speech models from scratch. We are using Vapi.ai (or Retell AI) for latency-optimized voice execution, connected via webhooks to a Next.js + Supabase web dashboard. Core Scope of Work (MVP) 1. AI Voice Telephony Module (Vapi.ai / Retell AI Integration) Outbound Campaign Launcher: Ability to upload a CSV of leads (Name, Phone Number, Context/Product) and trigger automated outbound AI voice calls via Vapi.ai / Retell AI. Inbound Call Handling: Connect an inbound SIP line (Twilio or Exotel) to a pre-prompted Vapi/Retell AI voice bot. Real-Time Webhook Processing: Capture call status, call recordings, audio transcriptions, and automated summaries generated by the LLM (gpt-4o-mini / Claude 3 Haiku). 2. Multi-Channel Chat Module (WhatsApp & Instagram) Integrate Meta WhatsApp Cloud API (or ManyChat/WATI API) to send automated responses, handle FAQs, and qualify leads based on intent. Comment-to-DM or Inbound Trigger: Basic automated workflow that captures incoming WhatsApp/Instagram messages and routes them through OpenAI API to reply instantly. 3. Unified Inbox & CRM Workspace (Next.js Front-End) Unified Conversations View: A single dashboard screen displaying ongoing/past interactions across Voice Calls, WhatsApp, and Instagram. Contact & Lead Pipeline: Simple lead table with status tags (e.g., Hot Lead, Follow-up Required, Not Interested, Closed), call recordings, and summary notes. Knowledge Base / System Prompt Manager: A section where admins can paste text/Upload PDFs to update the AI agent's business context. Technical Stack Requirements Front-End / Back-End: Next.js (React), TypeScript, Tailwind CSS, App Router Database & Auth: Supabase (PostgreSQL, Supabase Auth, Webhooks) Voice Engine: Vapi.ai or Retell AI API Telephony Provider: Twilio or Exotel (SIP Trunking) LLM Engine: OpenAI API (gpt-4o-mini) / Anthropic Claude API Messaging: Meta WhatsApp Cloud API / Webhooks Deployment: Vercel (Free/Hobby tier) Strict Project Constraints & Exclusions (Out of Scope) To keep this build within strict cost and time limits, DO NOT quote for: Building custom WebRTC, FreePBX, or native Speech-to-Text/Text-to-Speech models from scratch (must use Vapi/Retell). Complex multi-tenant billing/subscription system (Single account/Admin setup only for MVP). Complex custom mobile applications (Web Dashboard optimized for desktop/mobile browsers only). Milestones & Payment Structure Milestone 1 ($400): Architecture Setup, Supabase DB, and Vapi.ai / Retell AI Outbound & Inbound Voice Calling Webhooks. Milestone 2 ($400): WhatsApp Cloud API integration & Multi-channel message processing pipeline. Milestone 3 ($400–$700): Next.js Unified Inbox UI, Lead Management Table, Knowledge Base Prompt Manager, and Deployment to Vercel. How to Apply Please submit your proposal with: Proof or links to previous builds using Vapi.ai, Retell AI, or Next.js. Confirm that you can deliver this project within a 3 to 4-week timeline. Include the word "ORCHESTRATE" at the very top of your bid so I know you read the entire project description.

  • $1,000.00

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    Experience Level
  • Remote Job
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Skills and Expertise
Mandatory skills
AI Agent Development
API Integration
Activity on this job
  • Proposals:20 to 50
  • Last viewed by client:3 days ago
  • Interviewing:
    12
  • Invites sent:
    32
  • Unanswered invites:
    6
About the client
Member since Jul 30, 2026
  • India
    3:19 PM

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