Lead the full technical architecture and delivery of an AI voice agent system enhancing a live law firm phone infrastructure
Design and execute a phased PBX-to-SIP migration with rollback controls at every stage, keeping the firm operational throughout
Lead and coordinate a team of 2 OST engineers across the engagement for the MVP stage
Run weekly demos and maintain accessible test endpoints so both OST leadership and the client can verify progress firsthand
Define and own non-functional requirements: uptime, latency SLOs, observability, failover, and call quality monitoring
Break down the full implementation scope into clear phases (Phase 1 / 2 / 3), each delivering standalone value, paired with milestone-based payment checkpoints
Act as the primary technical voice with the client — translating complex infrastructure decisions into clear, confident guidance for non-technical stakeholders

Hands-on PBX-to-SIP migration experience — has personally moved a live organization off a traditional POTS/PBX system onto a modern SIP trunk (Twilio, Telnyx, Sierra, or equivalent); can speak fluently to the physical-to-software boundary gotchas
Phased rollout design — has built parallel SIP/legacy environments with incremental traffic shifting (1% → 5% → 25% → 100%) and rollback capability at every step
Production voice AI experience — has shipped real-time voice agent stacks using Retell, Vapi, LiveKit, or equivalent; understands latency budgets, turn-taking, and interruption handling
Privacy & compliance fluency — familiar with PII, financial data, attorney-client privilege, Retell BAA coverage, and data retention obligations for regulated environments
Non-functional requirements as a first-class concern — treats observability, uptime SLOs, failover, and call quality monitoring as core deliverables, not afterthoughts
Strong English communication — able to reassure non-technical stakeholders and run structured weekly demos for both the client and internal OST leadership

$150 – $200/hour — paid in USD via bank transfer (US-based candidates) or Deel (LATAM-based candidates)
Fully Remote — must have strong understanding of US market and phone systems
Freelance / Hourly contract — higher hours expected in the early project phases, tapering as the build stabilizes
Referral Program — earn a bonus for referring talent that gets hired

CTO – Technical Lead, AI Voice Agent, SIP Migration, Retell/Vapi

Key skills