Hire the Best AI Voice Agent Developers

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Daniel I.

Ado Odo, Nigeria

$20/hr
5.0
29 jobs

AI Voice Agent Developer specializing in Retell AI, Vapi, Twilio, GoHighLevel, AI Receptionist systems, Voice AI automation, and Conversational AI for businesses that need better call handling, lead qualification, appointment booking, CRM automation, missed-call follow-up, and inbound/outbound voice workflows. I build production-ready AI Voice Agents, AI Receptionists, website chatbots, and automation systems that answer calls, qualify leads, book appointments, transfer callers to a human, update your CRM, and trigger SMS or follow-up automations. If you need a Retell developer, Vapi developer, Twilio voice automation specialist, GoHighLevel AI expert, or AI chatbot developer, I build systems designed for real business use, not fragile demo bots. Most businesses donโ€™t have a lead problem. They have a response-time, call-handling, and follow-up problem. Missed calls, slow callbacks, poor qualification, manual scheduling, and disconnected tools all reduce conversion. I solve that by building Voice AI systems that work inside your real workflow and connect cleanly to your calendar, CRM, forms, pipelines, and backend tools. I design and deploy AI Voice Agents that can: Answer inbound calls 24/7 Sound natural using modern AI Text-to-Speech and Conversational AI Qualify leads and capture caller details Book appointments into your CRM or calendar Route or transfer calls to a real person Trigger SMS reminders, confirmations, and follow-up sequences Log call summaries, notes, tags, and outcomes automatically Support both inbound and outbound call flows Use live business data, not hardcoded responses What I build AI Receptionists for inbound calls, FAQs, call routing, and booking AI Voice Agents for lead qualification, follow-up calls, reactivation, and support Website chatbots connected to your CRM, calendar, and knowledge base GoHighLevel AI automation for missed-call text-back, pipeline updates, and workflows Retell AI / Vapi / Twilio systems with webhooks, APIs, custom logic, and call routing Appointment booking systems connected to GoHighLevel, Google Calendar, Calendly, and other tools Post-call automation for summaries, tagging, notes, CRM syncing, and follow-up sequences Core stack Retell AI, Vapi, Twilio, GoHighLevel, ElevenLabs, OpenAI, Python, Node.js, Make, n8n, Zapier, APIs, Webhooks, CRM Automation, Prompt Engineering, Conversational AI Typical use cases AI Receptionist for local service businesses Voice AI for dental, med spa, clinic, and healthcare booking workflows Lead qualification and follow-up for agencies and sales teams Missed-call automation for trades and home services Customer support chatbots and AI phone agents Twilio, Vapi, and Retell voice automation systems GoHighLevel CRM automation and pipeline workflows I work with businesses that depend on phone communication, speed-to-lead, and consistent follow-up, including local services, home services, trades, agencies, healthcare clinics, med spas, customer support teams, and lead generation businesses. My focus is always the same: build a system that is practical, reliable, scalable, and easy to manage. My process is simple: I map your call flow, define the business logic, build the AI system, connect the tools, test the workflow, and refine the conversation until it performs well in real usage. I focus on natural conversation flow, clean routing, CRM accuracy, reliable integrations, lead capture, appointment booking, and automation that reduces manual work. If you need an AI Voice Agent Developer, AI Receptionist expert, Retell AI specialist, Vapi developer, Twilio voice automation expert, GoHighLevel automation specialist, or Conversational AI builder, I can help you build a system that fits your business and your stack. Send me a message with: Your business type How calls are handled today Your current tools or CRM What you want automated Iโ€™ll review your setup and suggest the most practical approach for your AI Voice Agent, AI Receptionist, chatbot, or automation system.

  • Artificial Intelligence
  • AI Agent Development
  • Conversational AI
  • HighLevel
  • Twilio
  • Twilio API
  • API
  • API Integration
  • RESTful API
  • ElevenLabs
  • Make.com
  • n8n
  • OpenAI API
  • ChatGPT API
  • GPT-4
  • Python
  • FastAPI
  • Django
  • Chatbot
  • Chatbot Development
Joshua Ayomide S.

Akure, Nigeria

$20/hr
4.9
76 jobs

Are missed calls, slow follow ups, or manual lead handling costing your business opportunities? I help businesses build custom AI voice agents and automation systems that answer calls, qualify leads, schedule appointments, and follow up automatically so your team can focus on closing deals instead of chasing conversations. Many businesses in real estate, healthcare, and service industries lose potential clients simply because they cannot respond instantly. I build AI voice systems that handle conversations 24/7, while keeping everything synced with your CRM and workflows. My focus is simple: build AI systems that actually work inside real business operations. ๐€๐ˆ ๐•๐จ๐ข๐œ๐ž ๐€๐ ๐ž๐ง๐ญ๐ฌ & ๐‚๐š๐ฅ๐ฅ ๐€๐ฎ๐ญ๐จ๐ฆ๐š๐ญ๐ข๐จ๐ง I design and deploy AI voice agents that handle real customer conversations, book appointments, qualify leads, route calls, and trigger follow-up actions automatically. These systems include: โ€ข AI phone agents (inbound & outbound) โ€ข AI receptionists for service businesses โ€ข AI lead qualification agents โ€ข AI appointment scheduling systems โ€ข Intelligent IVR systems using Twilio, Retell AI, and Vapi โ€ข Real time voice AI using LiveKit and WebRTC I also build post call automation (summaries, CRM updates, tagging, notifications, and lead routing).. ๐‚๐ฅ๐š๐ฎ๐๐ž ๐‚๐จ๐๐ž & ๐€๐ˆ ๐€๐ ๐ž๐ง๐ญ ๐–๐จ๐ซ๐ค๐Ÿ๐ฅ๐จ๐ฐ๐ฌ I use Claude Code to design and power intelligent AI agent systems, structured prompt frameworks, and automation workflows used in real time voice and conversational AI. Claude Code is integrated into my workflow to build scalable, reliable, and production-ready AI systems. My work with Claude Code includes: โ€ข Building AI agent logic and structured prompt systems using Claude Code โ€ข Designing Claude Code workflows for conversational AI and decision making โ€ข Creating AI automation pipelines powered by Claude Code โ€ข Integrating Claude Code with APIs, CRMs, and backend systems โ€ข Combining Claude Code with Retell AI, Twilio, and Vapi for voice automation โ€ข Optimizing prompt engineering and response handling using Claude Code โ€ข Developing AI agent workflows for lead qualification, follow-ups, and automation Claude Code allows me to build smarter, more adaptive AI systems that operate efficiently inside real business workflows. ๐–๐จ๐ซ๐ค๐Ÿ๐ฅ๐จ๐ฐ ๐€๐ฎ๐ญ๐จ๐ฆ๐š๐ญ๐ข๐จ๐ง & ๐’๐ฒ๐ฌ๐ญ๐ž๐ฆ ๐ˆ๐ง๐ญ๐ž๐ ๐ซ๐š๐ญ๐ข๐จ๐ง I build automation systems that connect your tools and eliminate repetitive tasks. Using Make and n8n, I create workflows that manage leads, tasks, notifications, and CRM updates automatically. Automation solutions include: โ€ข Lead routing and assignment โ€ข Sales pipeline automation โ€ข Automated follow-ups and reminders โ€ข API and webhook integrations โ€ข CRM syncing and contact updates โ€ข Internal notifications and task automation ๐‚๐‘๐Œ ๐€๐ฎ๐ญ๐จ๐ฆ๐š๐ญ๐ข๐จ๐ง & ๐‹๐ž๐š๐ ๐Œ๐š๐ง๐š๐ ๐ž๐ฆ๐ž๐ง๐ญ I build smart CRM systems (especially GoHighLevel) that capture, nurture, and convert leads automatically. This includes: โ€ข GoHighLevel setup and automation โ€ข Lead nurturing systems โ€ข Twilio SMS automation โ€ข Booking and appointment reminders โ€ข AI powered lead qualification workflows โ€ข Pipeline automation and contact management ๐๐ฅ๐š๐ญ๐Ÿ๐จ๐ซ๐ฆ๐ฌ ๐ˆ ๐–๐จ๐ซ๐ค ๐–๐ข๐ญ๐ก Retell AI Vapi Twilio LiveKit Claude Code Make n8n GoHighLevel Webhooks & APIs Google Sheets HubSpot Salesforce ๐ˆ๐ง๐๐ฎ๐ฌ๐ญ๐ซ๐ข๐ž๐ฌ Real Estate Healthcare Service Businesses SaaS & Tech E-commerce ๐Œ๐ฒ ๐€๐ฉ๐ฉ๐ซ๐จ๐š๐œ๐ก โ€ข Natural, human like conversation flows โ€ข Reliable and scalable automation โ€ข Clean, stable integrations โ€ข Faster lead response time โ€ข Reduced manual workload โ€ข Better customer experience If you're looking for an AI voice agent developer, Twilio expert, Retell AI specialist, Vapi developer, Claude Code automation expert, or workflow automation specialist, I can help you design and implement a system that delivers real results.... Letโ€™s discuss your use case and build something that actually works. AI voice agent development, AI voice agents, custom AI voice agents, AI phone agents, conversational AI, voice AI development, AI call automation, AI IVR systems, Twilio voice, Twilio IVR, Twilio automation, Retell AI, Retell AI development, Vapi AI, Vapi voice agents, LiveKit voice AI, WebRTC voice agents, real-time voice AI, AI receptionist systems, Claude Code, Claude Code automation, Claude Code AI agents, Claude Code workflows, Claude Code prompt engineering, Claude Code integrations, Claude Code API integration, Claude Code backend automation, Claude Code conversational AI, Claude Code voice AI, Claude Code agent development, Claude Code system design, Claude Code CRM integration, Claude Code workflow automation, Claude Code real-time systems, Claude Code lead automation, Claude Code call automation, Claude Code AI workflows, Claude Code prompt systems, Claude Code structured prompts, Claude Code business automation, Claude Code AI solutions, Claude Code development

  • Artificial Intelligence
  • AI Agent Development
  • AI Chatbot
  • Zapier
  • Chatbot
  • API Integration
  • Twilio
  • Automation
  • Make.com
  • Appointment Setting
  • n8n
  • JSON
  • Node.js
  • OpenAI API
  • Python
  • LLM Prompt
  • Machine Learning
  • AI App Development
  • Claude
  • Azure OpenAI Service
Fuzail Raza K.

Karachi, Pakistan

$25/hr
5.0
3 jobs

Every lead that waits more than 2 minutes is a lead you're losing. GoHighLevel CRM Automation, AI Voice Agent systems, and n8n Workflow Automation close that gap. Built specifically for marketing agencies and local service businesses. Right now, somewhere in your pipeline, a lead just went cold. Not because your offer was wrong. Not because the timing was off. Because no one followed up fast enough and by the time someone did, they had already moved on. That gap between "lead comes in" and "lead gets contacted" is costing you revenue every single day and it's completely fixable. Marketing agencies and local service businesses hire me when they need one system that captures, qualifies, and converts leads through AI automation. No manual work, no dropped follow-ups, no wasted ad spend. HERE IS WHAT THAT LOOKS LIKE IN PRACTICE: 1. A med spa implemented a GoHighLevel CRM automation system with AI lead scoring, cutting response time from 8 minutes to 90 seconds via an AI voice agent. Manual follow-up dropped 85%. Appointments up 40%. 2. A pet grooming business replaced their entire booking operation with an n8n multi-agent workflow and automated lead qualification over SMS, handling 100+ daily interactions with zero staff. Repeat bookings up 35% in 6 weeks. 3. A B2B sales team deployed a fully automated lead enrichment pipeline with webhook API integration, cutting processing time from 60 minutes to 6 minutes and enrichment costs by 95%. Full case studies with technical breakdown in portfolio below. WHAT I BUILD FOR YOU: 1. GoHighLevel CRM Automation Pipeline setup, smart workflows, AI lead scoring, SaaS mode, snapshots, and sub-account management Built to turn your GHL into a fully autonomous client acquisition system 2. AI Voice Agent Systems Inbound and outbound AI calling agents via Retell AI and Vapi Automated lead qualification, AI appointment setter flows, and live transfer to human closers when needed 3. n8n and Workflow Automation Multi-agent n8n workflows, Make and Zapier automation Connecting your CRM, calendar, SMS, and data systems into one uninterrupted pipeline 4. Lead Generation and Nurturing Automation Meta Ads to CRM funnels, automated lead qualification sequences SMS and WhatsApp automation via Twilio so every lead enters a system the moment they raise their hand 5. API Integration and Data Pipelines REST API and webhook infrastructure, B2B lead enrichment systems, PostgreSQL data pipelines The backend layer that makes every automation reliable and scalable TECH STACK: Automation and CRM: GoHighLevel, n8n, Make, Zapier, HubSpot Voice and Messaging: Retell AI, Vapi, Twilio, WhatsApp API AI and Intelligence: OpenAI API, LangChain, GPT-4, AI Lead Scoring Backend and Data: FastAPI, Node.js, Python, PostgreSQL, Supabase Integrations: Apollo. io, REST APIs, Webhooks, Google Workspace APIs, Meta Ads API Every day your team handles manually is a day your system should have handled automatically. I respond to every message within 24 hours, usually faster. Send me a message describing where your leads are dropping off right now. I will map out exactly what is broken and how to fix it. Straight answer, no pitch, no obligation.

  • Automation
  • Automated Workflow
  • CRM Automation
  • Marketing Automation
  • n8n
  • AI Agent Development
  • Lead Generation
  • API Integration
  • Business Process Automation
  • Lead Nurturing
  • Appointment Setting
  • Chatbot Development
  • Twilio
  • OpenAI API
  • LangChain
  • Zapier
  • Prompt Engineering
  • VoIP
  • Conversational AI
  • Marketing Automation Software
Denys S.

Brooklyn, New York

$39/hr
5.0
26 jobs

๐Ÿš€ I help companies turn repetitive communication into intelligent, fully automated voice workflows. My AI Voice Agents sound natural, act fast, and integrate seamlessly with CRMs - helping you capture every lead, qualify calls, and schedule appointments 24/7. AI Voice Agent | Twilio | STT โ†’ TTS | ElevenLabs | RetellAI | Ultravox | Vapi | AI Chatbot | n8n | Zapier | Make | API Integration Expert ๐Ÿง  What I Build โœ” AI Inbound Agent - Handles calls, collects data, qualifies leads, and books meetings through PBX, Asterisk, or FreeSWITCH. ๐Ÿ”’ Data Security & Compliance First - I prioritize the security and privacy of every clientโ€™s data. For healthcare organizations and other sensitive industries, I can implement HIPAA compliance and follow best practices for data encryption, access control, and audit logging to ensure full protection. โœ” Outbound AI Voice Agent - Re-engages leads, follows up, and promotes offers automatically. โœ” Smart Receptionist for Clinics & Hotels - Manages bookings, reminders, and client inquiries 24/7 with Twilio and STT โ†’ TTS integrations. โœ” AI Recruiter - Screens applicants, evaluates answers, and syncs data with CRMs like HubSpot or Zoho. โœ” Real Estate Voice Assistant - Answers property questions, books showings, and confirms via SMS or calendar links. โœ” AI Chatbot & Call Assistant - Natural conversational bots built with n8n, Zapier, or Make, connected to CRMs and APIs. โœ” AI Voice Agent Development - Custom AI voice logic powered by ElevenLabs, RetellAI, Ultravox, or Vapi. โš™๏ธ How Collaboration Works โœ” Discovery & Demo - I show how an AI Voice Agent can qualify and convert leads in real time. โœ” Planning & Design - We define your goals, tone, and conversation logic. โœ” Development & Integration - I build your system end-to-end using Twilio, n8n, PBX, Asterisk, or FreeSWITCH. โœ” Testing & Refinement - I optimize tone, flow, and performance using real data and client feedback. ๐ŸŒŸ Recent Projects ๐Ÿš€ Dental Practice AI Receptionist - Automated 100% of inbound booking & reminders via phone and SMS. ๐Ÿš€ Recruitment AI Caller - Screened candidates using 10+ logic-based qualification layers. ๐Ÿš€ Hotel Voice Concierge - Automated check-in, digital tipping, and room service requests. ๐Ÿš€ Restaurant Assistant - Took reservations, handled menu questions, and synced with POS systems. โœ… Why Clients Choose Me โœ” Goal-driven development - I focus on KPIs: lead quality, conversion speed, and customer satisfaction. โœ” End-to-end delivery - From conversation design to full deployment with CRM and API Integration. โœ” Human-grade experience - Natural tone, contextual memory, and smart logic for fluid conversations. โœ” Data security first - For medical and enterprise clients, I can implement HIPAA compliance and robust encryption. ๐Ÿงฉ Technology Stack โœ” AI Voice Agent Development โœ” PBX / FreeSWITCH / Asterisk Configuration โœ” VoIP & Twilio Integration โœ” Speech-to-Text (STT) / Text-to-Speech (TTS) โœ” ElevenLabs / RetellAI / Ultravox Experts โœ” n8n Automation, Zapier, Make Workflow Builder โœ” CRM Integration (HubSpot, Zoho, Salesforce, GoHighLevel) โœ” API Integration & Workflow Automation โœ” AI Call Assistant / Voice Bot Development / Chatbot Automation โœ” LangChain, GPT, Whisper, OpenAI ๐Ÿ’ผ About Me Iโ€™m a hands-on AI Voice & Automation Developer with deep experience in PBX, Asterisk, FreeSWITCH, and VoIP architecture. I create intelligent conversational ecosystems that replace repetitive tasks with efficient AI-driven workflows - tailored to real business needs. ๐Ÿ“… Letโ€™s Talk If your business wants to: โœ” Automate lead communication and scheduling โœ” Eliminate missed calls and manual follow-ups โœ” Implement AI Voice Agents that sound human and work 24/7 Then letโ€™s connect. I offer a free 30-minute strategy session to identify the best AI Voice solution for your business.

  • Artificial Intelligence
  • n8n
  • Make.com
  • Zapier
  • API Integration
  • AI Agent Development
  • AI Chatbot
  • Deep Learning
  • Chatbot Development
  • AI Development
  • Asterisk
  • PBX
  • FreeSWITCH
  • Twilio
  • Natural Language Processing
Rahul K.

New Delhi, India

$25/hr
4.5
120 jobs

๐Ÿ“ฉ ๐—Ÿ๐—ฒ๐˜โ€™๐˜€ ๐—ฏ๐˜‚๐—ถ๐—น๐—ฑ ๐˜†๐—ผ๐˜‚๐—ฟ ๐—ป๐—ฒ๐˜…๐˜ ๐—”๐—œ ๐—ฏ๐—ฟ๐—ฒ๐—ฎ๐—ธ๐˜๐—ต๐—ฟ๐—ผ๐˜‚๐—ด๐—ต โ€” ๐—บ๐—ฒ๐˜€๐˜€๐—ฎ๐—ด๐—ฒ ๐—บ๐—ฒ ๐˜๐—ผ ๐—ด๐—ฒ๐˜ ๐˜€๐˜๐—ฎ๐—ฟ๐˜๐—ฒ๐—ฑ ๐˜๐—ผ๐—ฑ๐—ฎ๐˜†. ๐Ÿ”น Availability: Full-time (๐Ÿฐ๐Ÿฌโ€“๐Ÿฑ๐Ÿฌ ๐—ต๐—ฟ๐˜€/๐˜„๐—ฒ๐—ฒ๐—ธ) | Open to long-term and enterprise AI projects. ๐Ÿ”น Trusted AI/ML Engineer with ๐Ÿด+ ๐˜†๐—ฒ๐—ฎ๐—ฟ๐˜€ of Exp. delivering intelligent solutions for startups, SaaS ๐Ÿ”ด I am in the ๐—ง๐—ผ๐—ฝ ๐Ÿญ% overall on Upwork. ๐Ÿ”ด I am in the ๐—ง๐—ผ๐—ฝ ๐Ÿฎ% overall on StackOverflow. ๐Ÿ”น8+ Years of Experience as a Fullstack AI/ML Developer. ๐Ÿ”น $200K+ Billing done over upwork. ๐Ÿ”น 14000+ Hours on Upwork | 60+ Successful Projects Delivered. ๐Ÿ”น Worked with Fortune 100 Companies. ๐Ÿ”น Performance-Driven, Scalable & SEO-Optimized Web Applications. ๐—œโ€™๐—บ ๐—ฅ๐—ฎ๐—ต๐˜‚๐—น ๐—ž๐—ต๐—ฒ๐—ฟ๐—ฎ, ๐—ฎ ๐—™๐˜‚๐—น๐—น ๐—ฆ๐˜๐—ฎ๐—ฐ๐—ธ ๐—”๐—œ/๐— ๐—Ÿ ๐——๐—ฒ๐˜ƒ๐—ฒ๐—น๐—ผ๐—ฝ๐—ฒ๐—ฟ & ๐—œ ๐—ต๐—ฎ๐˜ƒ๐—ฒ ๐—ฒ๐˜…๐—ฝ๐—ฒ๐—ฟ๐—ถ๐—ฒ๐—ป๐—ฐ๐—ฒ ๐˜„๐—ถ๐˜๐—ต ๐—”๐—œ ๐—œ๐—ป๐˜๐—ฒ๐—ด๐—ฟ๐—ฎ๐˜๐—ถ๐—ผ๐—ป ๐—ฎ๐—ป๐—ฑ ๐—™๐—ฟ๐—ผ๐—ป๐˜๐—ฒ๐—ป๐—ฑ ๐—ฎ๐—ป๐—ฑ ๐—•๐—ฎ๐—ฐ๐—ธ๐—ฒ๐—ป๐—ฑ ๐——๐—ฒ๐˜ƒ๐—ฒ๐—น๐—ผ๐—ฝ๐—บ๐—ฒ๐—ป๐˜... ๐Ÿ”น Fine Tuning: Specialized in persona writing, QnA, medical, legal using mistral, llama3 ๐Ÿ”น LLM Synthetic Dataset Generation ๐Ÿ”น LLM Evaluation Framework ๐Ÿ”น LLM Deployment: On Cloud platforms like RunAPod, AWS, GCP ๐Ÿ”น AI Agents / Voice Bots: Proficient with CrewAI/AutoGen, Amazon Polly, Deepgram. ๐Ÿ”น OS LLM Deployment: On AWS/GCP/RunPod using SkyPilot (vLLM/TGI) ๐Ÿ”นPython (Flask, Fast API, Django, GPT API, Pytest, BeautifulSoup, Selenium) ๐Ÿ”น Web Scraping, Data Mining, Web Crawling, Data Parsing, Automation, Bots ๐Ÿ”น Fullstack (JavaScript, MongoDB, Express.js, React, Node.js) ๐Ÿ”น DevOps - Ansible, Docker, Kubernetes, GitLab CI\CD (AWS/Azure/DO/GCP). ๐Ÿ”น API integration: Binance API, Telegram API, OpenAI API, BetFair API, OddsJam API, Stripe API. ๐Ÿ”น API development: RESTful API, Web Services, HTTP Methods, JSON/XML, API Security, OAuth, API Documentation, API Testing, Postman, Swagger, API Gateway, Microservices, Endpoint Design ๐Ÿ“Œ ๐— ๐˜† ๐˜€๐—ฒ๐—ฟ๐˜ƒ๐—ถ๐—ฐ๐—ฒ๐˜€ ๐—ถ๐—ป๐—ฐ๐—น๐˜‚๐—ฑ๐—ฒ ๐Ÿ“Œ โš™๏ธ Web Scraping | Data Mining | Data Extraction โš™๏ธ Web Automation | Data Cleaning | Data Collection โš™๏ธ Crypto Trading Automation | Automate Trading Strategy โš™๏ธ Interactive Brokers Bot | Crypto Trading Bot | Dashboard โš™๏ธ Data Analysis | Data Visualization | Data Entry โš™๏ธ Auto Fill Web Forms (Just a click away!) โš™๏ธ Merge Multiple CSV Files into a Master File โš™๏ธ Custom Scripting for Your Specific Needs ๐— ๐˜† ๐—ฆ๐—ธ๐—ถ๐—น๐—น๐˜€๐—ฒ๐˜: โคต๏ธ AI Agents, Voice Agents, CrewAI, AutoGen, Hugging Face, LLaMA 3, Mistral 7B, PEFT, LoRA, QLoRA, Prompt Engineering, RAG Pipelines, LangChain, Vector Databases, FastAPI, Flask, Django, Streamlit, Azure OpenAI, OpenAI API, vLLM, GPTQ, Trading Bots, Binance API, Telegram Bot API, Python, Selenium, Scrapy, Playwright, BeautifulSoup, Regex, REST APIs, Pandas, NumPy, Scikit-learn, PostgreSQL, Firebase, MongoDB, Data Analysis, Data Engineering ๐Ÿ“Œ ๐—”๐—œ ๐—˜๐˜…๐—ฝ๐—ฒ๐—ฟ๐˜๐—ถ๐˜€๐—ฒ & ๐—ฆ๐—ฝ๐—ฒ๐—ฐ๐—ถ๐—ฎ๐—น๐—ถ๐˜‡๐—ฎ๐˜๐—ถ๐—ผ๐—ป๐˜€:๐Ÿ“Œ ๐Ÿ”น๐—”๐—œ ๐—”๐—ด๐—ฒ๐—ป๐˜๐˜€ / ๐—ฉ๐—ผ๐—ถ๐—ฐ๐—ฒ ๐—”๐—ด๐—ฒ๐—ป๐˜๐˜€: CrewAI, AutoGen, Amazon Polly, Deepgram. ๐Ÿ”นL๐—Ÿ๐—  ๐—™๐—ถ๐—ป๐—ฒ๐˜๐˜‚๐—ป๐—ถ๐—ป๐—ด & ๐—ง๐—ฟ๐—ฎ๐—ถ๐—ป๐—ถ๐—ป๐—ด: PEFT, LoRA, QLoRA, RLHF, DPO with Unsloth, Axolotl, Hugging Face. ๐Ÿ”น๐—ข๐—ฝ๐—ฒ๐—ป-๐—ฆ๐—ผ๐˜‚๐—ฟ๐—ฐ๐—ฒ ๐—Ÿ๐—Ÿ๐— ๐˜€: LLaMA 3, Mistral 7B, Mixtral 8x7B. ๐Ÿ”น๐—™๐—ฎ๐˜€๐˜ ๐—œ๐—ป๐—ณ๐—ฒ๐—ฟ๐—ฒ๐—ป๐—ฐ๐—ฒ & ๐—ฆ๐—ฒ๐—ฟ๐˜ƒ๐—ถ๐—ป๐—ด: vLLM, TGI, DeepSpeed. ๐Ÿ”น๐——๐—ฒ๐—ฝ๐—น๐—ผ๐˜†๐—บ๐—ฒ๐—ป๐˜ & ๐—œ๐—ป๐˜๐—ฒ๐—ด๐—ฟ๐—ฎ๐˜๐—ถ๐—ผ๐—ป: API-first architecture, Streamlit, Gradio, LangChain, CrewAI. ๐Ÿ”น๐—ฃ๐—ฟ๐—ผ๐—บ๐—ฝ๐˜ ๐—˜๐—ป๐—ด๐—ถ๐—ป๐—ฒ๐—ฒ๐—ฟ๐—ถ๐—ป๐—ด & ๐—ฅ๐—”๐—š ๐—ฃ๐—ถ๐—ฝ๐—ฒ๐—น๐—ถ๐—ป๐—ฒ๐˜€: Custom GPT-4 workflows, Multi-agent orchestration, vector search integration. Quantization & Optimization: AWQ, GPTQ, GGUF, GGML. I believe in creating lasting partnerships with my clients by delivering projects on time and exceeding expectations. I look forward to bringing my technical expertise and passion for software development to your project and making a meaningful impact. Thanks Rahul Khera

  • AI Bot
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  • AI Agent Development
  • AI Mobile App Development
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Waqar Hussain S.

Fort McMurray, Canada

$15/hr
4.6
70 jobs

I ๐—–๐—ข๐—ก๐—ฆ๐—จ๐—Ÿ๐—ง first, then ๐—”๐—จ๐—ง๐—ข๐— ๐—”๐—ง๐—˜. If you already know ๐’†๐’™๐’‚๐’„๐’•๐’๐’š what needs to be automated and how, we can jump straight into execution. But in most cases, thatโ€™s not where the real value lies. I prefer starting with a call, proper discussion - understanding your current (manual) workflows, identifying gaps, and mapping out a clear, phased roadmap. Only then do we move into execution. Because hereโ€™s the truth: Most developers skip this stepโ€ฆ and end up causing delays, rework, and unnecessary complexity. I ๐’…๐’๐’โ€™๐’•. _____________ Are your leads slipping through the cracks? Spending hours on tasks that should run themselves? I help businesses like yours automate operations using powerful no-code AI tools, such as n8n, Make com, Zapier, and GoHighLevel (GHL), combined with cutting-edge AI like GPT-4, ElevenLabs, Vapi, Retell AI and ManyChat. The result? Smart systems that generate leads, follow up, and close more deals while you sleep, and customer service that runs on autopilot, 24/7! DevOps Since 2021, Iโ€™ve built high-converting AI automations and AI integrations for real estate agencies, healthcare providers, travel companies, recruiters, and online service businesses. Iโ€™ve deployed: โœ… End-to-end CRM workflows with GoHighLevel AI โœ… AI chatbots and WhatsApp agents powered by GPT & n8n โœ… AI Lead capture and outreach pipelines with n8n + Make โœ… Voice-enabled assistants using Retell AI, Vapi, and ElevenLabs โœ… AI Auto-reply and support bots integrated with websites and Facebook โœ… WhatsApp follow-up and qualification AI bots DevOps โœ… Lead-to-appointment automations synced with calendars and CRMs ๐๐จ๐ญ๐š๐›๐ฅ๐ž ๐ฉ๐ซ๐จ๐ฃ๐ž๐œ๐ญ๐ฌ: - evolveworkforcesolutions com โ€“ AI scheduling and follow-up for recruiting - klikdigital nl โ€“ Dutch AI Voice Receptionist for lead follow-up and nurturing - oxygenbar360 com โ€“ real-time WhatsApp chatbot for every booking Healthcare practice โ€“ multilingual AI voice agent for triage & appointment setting Whether you need a one-time workflow, a scalable AI system, or ongoing automation support, Iโ€™m here to deliver results fast, clean, and fully documented. ๐Ÿ›  Available for: Workflow Automation (n8n, Make, Zapier, GHL) AI Agents & GPT-4 Integrations Voice Bots (Vapi, ElevenLabs, Retell) WhatsApp, SMS & Web Chatbots CRM Setup & Automation (GHL, HubSpot, Pipedrive) Letโ€™s build a system that works while you donโ€™t have to.

  • Tech & IT
  • AI Agent Development
  • AI Chatbot
  • n8n
  • AI Bot
  • Make.com
  • ChatGPT
  • Twilio
  • Automation
  • API Integration
  • AI Consulting
  • AI Builder
  • ManyChat
  • Zapier
  • ElevenLabs

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Don't just take our word for it

AI voice agent developer hiring guide

AI voice agent developers use natural language processing, speech-to-text (STT), and text-to-speech (TTS) to build conversational AI systems that handle phone calls, appointments, customer support, sales outreach, and more. These specialists integrate platforms like Vapi, Voiceflow, and Synthflow AI with business systems, creating voice experiences that reduce call center costs and improve around-the-clock availability. 

What does an AI voice agent developer do?

AI voice agent developers design, build, and deploy conversational voice systems. They combine expertise in artificial intelligence, natural language processing, and telecommunications infrastructure to create voice agents that qualify leads, schedule appointments, answer support questions, and handle other voice-based workflows.

Core responsibilities include:

  • Building conversation flows using platforms like Vapi or Voiceflow to map out responses to customer intents and handle interruptions.

  • Integrating with business systems (CRMs, calendars, databases, APIs) to access customer data and trigger actions.

  • Optimizing voice quality and performance by fine-tuning TTS and STT pipelines for sub-200ms response times.

  • Implementing phone system connectivity using services like Twilio, Telnyx, or Plivo.

  • Testing and iterating voice AI for edge cases, background noise, accents, and network issues.

How to hire an AI voice agent developer on Upwork

Upwork makes it easy to find, vet, hire, and collaborate with AI voice agent developers at all skills levels. Depending on your needs, youโ€™ll want to focus on technical skills (API integration, conversation design, latency optimization) and platform expertise (Vapi, Voiceflow, Twilio). You only need to follow these four simple steps.

Step 1: Post a job

Your job post is the first point of contact candidates will have with your project. A well-crafted job description will help qualified freelancers find your project as they search for work. In your post:

  • Use a keyword-rich title like โ€œAI voice agent developer needed for customer supportโ€

  • Describe your project so candidates understand what the agent should do and which systems it needs to integrate with

  • Define the core objective, such as qualifying inbound sales leads or scheduling customer appointments

  • List required technical integrations like Salesforce, HubSpot, Calendly, Twilio, or Telnyx

  • Cover technical details such as your budget and timeline

To create a tailored job post quickly, try the Job Post Generator powered by Umaโ„ข, Upworkโ€™s Mindful AI. Describe what you need in a few sentences, and Uma will craft a job post in seconds. You can also review job description templates and examples for inspiration.

Step 2: Filter and evaluate candidates

As proposals come in, youโ€™ll want to review them in a way that is thorough and efficient. 

  • Have Uma give instant video interviews and side-by-side comparisons

  • Use Upworkโ€™s filters to find candidates by rate, location, and experience

  • Review proposals for signs that the candidate has understood your job post and has the skills to meet your needs

  • Look through portfolios for case studies of voice AI projects, sample conversation flows, or links to deployed voice agents

  • Review client feedback for mentions of latency optimization, problem-solving ability, and on-time delivery

Step 3: Interview your top choices

A quick video interview gives you the chance to ask any questions you have left for your top choices, and to get a feel for what a collaboration with them might be like.

  • Schedule and conduct interviews within Upwork messaging to get instant transcripts and summaries from Uma

  • Have the candidate walk you through a piece from their portfolio, focusing on how the candidateโ€™s technical competency helped meet the clientโ€™s goals

  • Ask about their voice AI development process, including conversation design and latency optimization (targeting under 200ms)

  • Request examples of voice agents they've built, ideally demonstrating live agents

  • Ask how they handle conversation interruptions, background noise, and off-script user responses

  • Talk through their preferred TTS and STT providers and the reasoning behind their choices

If youโ€™re unfamiliar with interviewing freelancers, you can refer to common interview questions to help keep your conversations focused and productive. You can also look to interview questions for AI engineers for ideas from a related field.

Step 4: Agree on scope and begin work

Once youโ€™ve found the right person, you can send a contract directly through the Upwork marketplace. A solid contract protects both parties and helps collaborations be successful from beginning to end.

  • Use Upwork's contract workroom, messaging, and payment protection for secure collaboration

  • Choose fixed-price contracts for projects with clear deliverables, such as creating an appointment booking voice agent

  • Separate complex projects into clear milestones, such as requirement gathering, the core build, adding advanced features, testing, and iteration

  • Choose hourly contracts for ongoing work or projects without clear deliverables, such as ongoing maintenance, performance reporting, and training updates

Upwork is not affiliated with and does not sponsor or endorse any of the tools or services discussed in this article. These tools and services are provided only as potential options, and each reader and company should take the time needed to adequately analyze and determine the tools or services that would best fit their specific needs and situation.

The rates and information provided in this article are based on current data and industry sources available at the time of publication. Freelance rates can vary depending on factors such as experience, location, project scope, and market conditions. Readers are encouraged to conduct their own research to confirm current rates and trends, as this information may change over time.

How much does hiring an AI voice agent developer cost?

Independent professionals on Upwork base their rates according to market demand, the scope and complexity of the project, and their own skills and expertise. The following chart lists typical prices for AI voice agent developer projects commonly found on Upwork.

Appointment booking voice agent

$500-$1,500 /project

Entry- to mid-level
  • IVR menu and FAQ bot using Vapi or Voiceflow templates
  • Calendar integration for appointment scheduling
  • Testing and deployment

CRM-integrated voice agent

$2,500-$7,500 /project

Mid- to senior-level
  • Custom conversation flows with lead qualification logic
  • CRM integration (Salesforce, HubSpot)
  • Quality testing and documentation

Multi-agent telephony system

$10,000+ /project

Senior-level or specialist
  • Multiple conversation paths with advanced NLP
  • Custom API integrations with compliance (HIPAA)
  • Latency optimization under 200ms

Ongoing voice AI optimization retainer

$2,000-$8,000 /month

Mid- to senior-level
  • Conversation flow A/B testing and optimization
  • Integration maintenance and performance reporting
  • Agent training data updates

Voice AI strategy and architecture consulting

$5,000-$15,000+ /project

Expert- or executive-level
  • Voice AI roadmap and platform selection
  • Multi-agent orchestration planning
  • ROI analysis and team training

FAQs about AI voice agent developers

Frequently asked questions

Is hiring an AI voice agent developer worth it?

Yes, hiring an AI voice agent developer can deliver significant ROI, especially for businesses handling high call volumes. Voice AI agents provide 24/7 availability, instant response times, and consistent quality for appointment scheduling, lead qualification, and customer support. However, voice AI works best for structured, repeatable conversations. Emotional or complex support issues still need human agents.

What platforms do AI voice agent developers typically work with?

AI voice agent developers typically work with platforms like Vapi (API-first voice infrastructure), Voiceflow (visual conversation design), Synthflow AI (enterprise-ready agents), Bland AI, and Retell AI. Developers also work with telephony providers like Twilio, Telnyx, and Plivo for phone number provisioning and call routing.

How long does it take to build a voice AI agent?

A basic appointment booking agent using platform templates might launch in one to two weeks. Projects with custom conversation flows and CRM integration typically take four to six weeks. Enterprise systems with multiple agents and compliance requirements can require two to three months or more.

What's the difference between a chatbot developer and an AI voice agent developer?

Chatbot developers focus on text-to-text communication. Voice agent developers, on the other hand, need additional skills beyond text chatbot development, specifically STT and TTS API integration, latency optimization, and phone system integration. Voice agents must respond instantly (ideally below 300-500ms) and handle voice-specific challenges like background noise, accents, and interruptions.

Do I need a developer if I'm using a platform like Vapi or Voiceflow?

While platforms provide low-code tools, hiring a developer adds significant value for production systems. Developers build custom integrations with your CRM or proprietary APIs, optimize conversation flows, implement advanced error handling, and troubleshoot production issues.