AI Voice Calling Agent Developer | n8n, OpenAI/Claude API, Twilio/Vapi
Worldwide
We're looking for an experienced AI Automation Expert to build an AI-powered calling agent that can handle outbound/inbound calls, hold natural conversations, and complete tasks like lead qualification, appointment booking, customer support, or follow-ups. You'll be responsible for designing the full voice AI pipeline using n8n, OpenAI/Claude API, and voice/telephony platforms. Responsibilities: Build and deploy an AI voice calling agent capable of natural, human-like conversations Integrate voice platforms (e.g., Vapi, Retell AI, Bland AI, Twilio, or similar) with LLM backends (OpenAI/Claude) Design conversation flows, scripts, and prompts for different call scenarios (sales, support, scheduling, surveys, etc.) Set up n8n workflows to handle call triggers, data logging, CRM updates, and post-call actions Implement speech-to-text and text-to-speech pipelines with low latency Handle call routing, fallback logic, voicemail detection, and call transfers to humans when needed Integrate with calendars (Google Calendar/Calendly) for automated appointment booking Log call data, transcripts, and outcomes into CRM/Google Sheets/Airtable Test and optimize for natural conversation flow, interruption handling, and reduced latency Ensure compliance with call regulations (TCPA, DND lists, etc. if applicable) Requirements: Proven experience building AI voice agents/calling bots (please share demos) Hands-on experience with voice AI platforms: Vapi, Retell AI, Bland AI, Synthflow, or Twilio Voice/Media Streams Strong experience with OpenAI API and/or Claude API (prompt engineering, function calling, real-time responses) Experience with n8n for backend workflow automation (webhooks, HTTP requests, data handling) Understanding of STT/TTS tools (Deepgram, ElevenLabs, Whisper, PlayHT, etc.) Experience integrating with CRMs (GoHighLevel, HubSpot, Salesforce) is a plus Ability to optimize for low latency and natural conversational pacing Strong problem-solving skills and attention to detail in conversation design Nice to Have: Experience with outbound cold-calling or appointment-setting bots Background in building multi-turn conversational AI with memory/context handling Knowledge of Python/JavaScript for custom middleware Experience with call analytics and sentiment analysis How to Apply: Please share: A demo or recording of an AI calling agent you've built (even a sample call) The tech stack you used (voice platform + LLM + automation tool) A brief note on how you'd approach latency and natural conversation flow for this project
$100.00
Fixed-price- ExpertExperience Level
- Remote Job
- One-time projectProject Type
Skills and Expertise
Activity on this job
- Proposals:50+
- Interviewing:0
- Invites sent:0
- Unanswered invites:0
About the client
- United KingdomBelfast12:09 AM
- $8.7K total spent247 hires, 5 active
- 240 hours
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