Hire Voice AI Developers - Voice Bot, STT/LLM/TTS Pipeline & LiveKit Agents Specialists
Dedicated voice AI developers with expertise in voice bot development, LiveKit Agents SDK, Deepgram STT, GPT-4o LLM orchestration, ElevenLabs TTS, VAPI, Retell AI, Whisper ASR, and SIP trunk integration for inbound/outbound AI phone agents. Starting from $25/hr with 48-hour onboarding and 30-day money-back guarantee.
Hire Voice AI Developers
Expert voice bots, STT/LLM/TTS pipelines, and LiveKit Agents. Build conversational phone systems.
Technology Stack
Voice AI Platforms
Speech-to-Text (STT)
LLM & Orchestration
Text-to-Speech (TTS)
VoIP Integration
Backend & Infra
Developer Roles Available
Senior Voice AI / Voice Bot Developer
$25/hrLiveKit Agents SDK, Deepgram, GPT-4o, ElevenLabs, Cartesia, SIP trunk integration
End-to-end voice pipeline expert with production deployment experience
LLM Integration & Prompt Engineer
$28/hrGPT-4o, Claude, Gemini, LangChain, RAG, function calling, conversation management
Specialized in LLM orchestration for voice interaction design
VAPI / Retell AI Developer
$25/hrVAPI platform, Retell AI, Bland AI, outbound campaigns, webhook integration, analytics
Managed platform specialist for rapid voice AI deployment
Voice AI + VoIP Infrastructure Developer
$38/hrLiveKit + Asterisk/FreeSWITCH SIP integration, PSTN inbound/outbound, SIP trunk config
Full-stack voice AI with deep VoIP infrastructure expertise
Common Use Cases
AI Customer Service Bot
24/7 inbound voice bot handling tier-1 support: FAQs, account lookups, and ticket creation
Appointment Scheduling Agent
AI phone agent that checks calendar, confirms availability, and books appointments via voice
AI Lead Qualification Bot
Outbound calling bot that qualifies leads, scores intent, and hands off to human sales
IVR Replacement Agent
Conversational AI replacing touchtone IVR — natural language routing without menu trees
Collections Voice Agent
Compliant outbound collections bot with payment processing and escalation logic
Healthcare Triage Voice Bot
HIPAA-compliant symptom collection, appointment booking, and care team routing via voice
How We Compare
| Provider | Rate | Expertise | Onboarding |
|---|---|---|---|
| CelloIP | $25/hr | Voice AI + VoIP vetting | 48hrs |
| Specialist Freelancers | $60-120/hr | Self-reported skills | 1-7 days |
| US AI Agencies | $150-300/hr | Full-service AI | 3-6 weeks |
| VAPI/Retell Managed | $0.05-0.15/min | Platform cost (no dev) | N/A |
| Offshore General Dev | $15-30/hr | No voice AI expertise | Unknown |
Our Hiring Process
Requirements
Describe your voice AI bot or integration needs
Match Developer
We find the right voice AI specialist for your project
Architecture Review
Live discussion of STT/LLM/TTS pipeline design
Trial Project
2-week trial on actual work with refund guarantee
Production Ready
Fully productive and integrated within 48 hours
Our Guarantees
30-Day Refund
Full refund if not satisfied
48-Hour Onboarding
Productive immediately
Top 3% Vetted
Expert voice AI developers
24-Hour Swap
Instant replacement if needed
What Clients Say
"Our HIPAA appointment booking bot handles 2,000+ calls/day. The developer built the LiveKit + Deepgram + GPT-4o pipeline, SIP trunk integration, and fallback to human agent in 6 weeks. Patient satisfaction scores improved by 34%."
Rachel Thompson
HealthCall Solutions
"Outbound lead qualification bot calling 500 leads/day. The voice AI developer tuned the conversation flow, barge-in detection, and CRM webhook integration. Qualified lead rate is now 3x our human team at 20% of the cost."
Ben Goldstein
SalesForce Automation
"Collections voice agent — compliant, multilingual, and integrated with our billing system. The developer handled the LiveKit SIP integration, compliance guardrails, and payment IVR handoff. Fully operational in 8 weeks."
Yuki Tanaka
FinServ Connect
Frequently Asked Questions
What does a voice AI developer do?
A voice AI developer builds end-to-end conversational phone systems where AI handles voice calls autonomously: speech-to-text (STT) converts caller audio to text, a large language model (LLM) processes intent and generates a response, and text-to-speech (TTS) converts it back to audio — all in under 500ms. They integrate these pipelines with VoIP infrastructure (Asterisk, FreeSWITCH, LiveKit) for inbound/outbound phone call handling.
LiveKit vs VAPI vs Retell — which platform should we use?
LiveKit Agents SDK is open-source and self-hostable — best for teams wanting full control, custom models, or regulated industries (HIPAA/PCI). VAPI is a managed platform with rapid deployment but less customizability. Retell AI offers a no-code-friendly API with built-in telephony. CelloIP recommends LiveKit for production enterprise deployments and VAPI/Retell for rapid prototyping.
What is the minimum latency for a voice AI agent?
With streaming STT (Deepgram Nova-2) + streaming LLM (GPT-4o with token streaming) + streaming TTS (ElevenLabs or Cartesia), end-to-end latency is 400–600ms. Using OpenAI Realtime API (voice-to-voice) or Gemini Live, latency drops to 200–300ms. Our developers optimize each pipeline stage for the lowest achievable latency.
How much does voice AI / voice bot development cost?
A production voice bot (inbound or outbound, single use case) typically costs $15,000–$40,000 including STT, LLM, TTS pipeline, SIP integration, and testing. Our dedicated voice AI developers at $25–38/hr deliver this 50–60% cheaper than US AI agencies at $150–300/hr.
Can voice AI bots handle HIPAA-compliant calls?
Yes. For HIPAA compliance we use self-hosted Whisper (on-premise STT), a BAA-covered LLM (Azure OpenAI or self-hosted Llama 3), and encrypted SIP (SRTP/TLS). No PHI leaves your controlled infrastructure. Our developers have delivered HIPAA-compliant voice AI for multiple healthcare clients.
What languages can voice AI agents support?
Deepgram supports 30+ languages with excellent accuracy. ElevenLabs and Cartesia offer multilingual TTS with natural voice quality. LLMs like GPT-4o and Claude handle multilingual conversation natively. Our developers have deployed voice agents in English, Spanish, French, German, and Hindi.
Other Specialized Roles
Voice AI Development Resources
Voice Bot Development Service
Dedicated voice bot & conversational IVR
LiveKit Voice Agents Service
STT→LLM→TTS pipeline, sub-500ms latency
AI VoIP Integration
GPT-4o IVR, Whisper ASR, ElevenLabs TTS
LiveKit Platform Development
Real-time audio/video infrastructure
Voice Agents Build Guide 2026
Complete guide: STT, LLM, TTS pipeline
GPT-4 IVR on Asterisk Guide
Building AI IVR with AGI and Whisper
Voice Bot Development: 2026 Guide
Full STT→LLM→TTS architecture and platform comparison
VAPI vs Retell vs LiveKit vs Bland AI
Side-by-side voice AI platform comparison
HIPAA-Compliant Voice AI Agents
BAA requirements, encryption, audit logging
Hire AI Developers
LLM, Whisper ASR, conversational AI experts
Developer FAQs & Pricing
Rates, timelines & engagement models
Ready to Build Your Voice AI Bot?
Find your voice AI expert in 48 hours. 30-day money-back guarantee.