Vantaca

Senior Backend Engineer — AI Voice Agent Platform (All Levels)

Redwood City, USA · Senior

Sponsorship not specifiedDetected 190 days ago

Distributed SystemsBackend DevelopmentAPI DevelopmentWebSocketsMachine LearningLLMsAgentic AILangGraphIncident ResponseValuationVoIPMentoring

About the role

These AI Agents go beyond traditional AI by proactively executing complex, multi-step processes with human-like reasoning-working autonomously, 24/7, across your entire operation.
HOAi was acquired by Vantaca in the fall of 2024.
The backend powers session orchestration, streaming pipelines, tool execution, integrations, and the data layer that makes voice agents reliable, debuggable, and continuously improving.

Own voice agent backend services: session lifecycle, call routing, participant management, conversation state, and real-time orchestration.
Build streaming pipelines: integrate and operate STT/TTS and real-time model endpoints; manage latency budgets, backpressure, and jitter.
Agent runtime + tools: implement tool calling, sandboxed execution, retries/idempotency, rate limits, and per-tenant budgets/quotas.
Integrations: telephony/RTC providers, calendars/CRMs/support tools, webhooks, and event streams; build durable sync adapters.
Data platform: model and store transcripts, audio metadata, agent actions, outcomes, evaluations, and audit trails; optimize for query + replay.
Growing 100% year-over-year Our AI product (HOAi) went from $0 to millions in months Backed by Cove Hill Partners and JMI Private Equity 6M+ doors on our platform, displacing legacy systems About the role We're building a production-grade AI voice agent platform that supports real-time, low-latency conversations at scale.
integrate and operate STT/TTS and real-time model endpoints; manage latency budgets, backpressure, and jitter.
Creates opportunities for team members to stretch their capabilities, providing coaching and support that helps them reach their full potential.
We're building something cool and people like it here.

Voice/real-time experience: WebRTC/RTC providers, telephony, streaming audio, SIP concepts, jitter/packet loss mitigation.
LLM and agent architecture experience: tool calling, planning/execution loops, memory/state, eval harnesses.
Familiarity with SDKs/frameworks: LiveKit, Twilio/telephony stacks, Vercel AI SDK, LangChain/LangGraph, Anthropic Agents SDK.
Experience with observability for real-time systems (OpenTelemetry traces spanning streaming + async workflows).
The HOAi Way Shoot for Impossible and Make it Happen: Sets audacious goals that others might see as unreachable and breaks them into actionable steps.
Stays open-minded on the path to continuous improvement, recognizing that the best outcomes come from carrying no ego.
Why You Should Join Our Team Our eNPS is +68! (Google it, that is great).
WebRTC/RTC providers, telephony, streaming audio, SIP concepts, jitter/packet loss mitigation.

Medical, Dental, and Vision kick in day one.
Unlimited PTO (with a requirement for employees to take a minimum of one continuous week per year).
Great parental leave benefits.
Relentlessly perseveres through obstacles with resourcefulness and determination, turning ambitious vision into tangible results.
Remote Flexible - come to the office when needed.

Description HOAi is a fast-growing startup revolutionizing the community association management industry.
Our AI workforce platform integrates machine learning technology to streamline labor-heavy processes, eliminating inefficiencies and driving scalability.
With rapid growth in the AI space, we are pushing boundaries to redefine industry standards.
HOAi is the leading AI solution for the community association management industry, enabling organizations to deploy AI Agents that function like experienced managers.
This transformation optimizes labor costs, enables growth without additional hires, and ensures faster, higher-quality service for residents and board members.
Vantaca just achieved unicorn status with a $1.25B valuation, so it's safe to say we're past the "scrappy startup phase." We're not just building a successful company - we're building the category-defining platform that will transform how an entire industry operates.

This listing is sourced directly from Vantaca's careers page and normalized into a canonical job model.