Senior AI Engineer

About UsXtnsion.AI is building the agentic CX layer for modern businesses — AI voice + chat agents that autonomously handle bookings, lead follow-up, support workflows, CRM actions, and more across phone, WhatsApp, SMS, email, and web chat.Our agents understand intent, retrieve context, take actions, and close loops — not just respond.We’re growing fast across healthcare, clinics, D2C, and global SMBs, and we’re hiring a senior builder to help architect our core platform from the ground up.About the RoleWe’re looking for a Senior AI Engineer (Founding Team) who loves building 0→1 products, thrives in chaos, and wants to work directly with the founder to architect and ship real agentic AI systems.You’ll design and build : Real-time voice + chat agentsAgentic reasoning and workflowsMemory + state managementDeep API integrations (CRM, scheduling, support tools)Scalable backend + infra for AI systemsThis is a high-ownership, high-autonomy, zero-bureaucracy role.What You’ll OwnArchitect the agentic workflow engine (reasoning, memory, tool use)Build real-time voice + chat agents using STT / TTS + LLMsCreate deep integrations with CRMs, schedulers, helpdesks, databasesDesign scalable backend + infra for multi-channel agentsPrototype fast, ship fast, and iterate with real customer feedbackWork directly with the founder on product + architectureLay the engineering foundation for the next 6–12 months of growthWhat You Bring4–7+ years of engineering experienceStrong backend fundamentals (Python preferred)Deep understanding of full-stack system design — backend services, SQL data modeling, and production-grade Python engineeringExpert-level understanding of APIs — requests, auth flows, webhook systems, rate limits, and complex third-party integrationsHands-on with LLM APIs, LangChain / LangGraph, agent orchestrationStrong grasp of Generative AI fundamentals — RAG, embeddings, retrieval design, structured outputs, and tool-using agentsExperience deploying and maintaining production systems — Docker, servers, environment management, and dev / stage / prod setupsArchitectural intuition around scalable systems — queues / workers, caching, load balancing, service boundaries, and latency-aware designExperience with chat / voice systems or workflow automationComfortable using AI-augmented developer tools (Cursor, ChatGPT, Gemini, Claude) to accelerate prototyping and developmentComfortable integrating complex APIsThrive in zero-to-one environments, ambiguity, and high ownershipWhy You’ll Love ThisDirect collaboration with the founderMassive ownership and zero bureaucracyBuild systems that thousands will interact with dailyRemote-first, flexible, output-driven culturePath to Lead Engineer / Head of EngineeringIf you’re a builder, problem-solver, and 0→1 engineer, let’s talk.