Senior AI Fullstack Engineer

About EteraEtera is building the first AI-native corporate travel platform for the GCC market — designed from the ground up for how businesses in the region actually operate. We're a lean, high-conviction team replacing legacy TMCs with autonomous agents, real-time inventory, and a product experience that doesn't feel like it was designed in 2009.The RoleWe're looking for a Senior AI Fullstack Engineer who can own the full stack — from a smooth React Native mobile experience to TypeScript backend services and the AI/LLM layer that powers our multi-agent infrastructure (OPUS Prime). If you think in systems, ship fast, and find it natural to reason about both user-facing product and underlying model behavior, this role was built for you.What You'll OwnMobile-first product: Build and maintain Etera's React Native app (Expo/TypeScript) — booking flows, real-time updates, multilingual UX (Arabic/English)Backend services: Design and extend our TypeScript backend, including booking APIs, supplier integrations (PKfare, RateHawk, Hotelbeds), and webhook orchestrationLLM integration: Work directly with Claude (Anthropic API) and our multi-agent OPUS Prime system — building, tuning, and extending AI pipelines for travel intent detection, QA, and automated engineering reportsEnd-to-end delivery: Take features from spec to production. Own the full lifecycle — architecture, implementation, testing, deploymentInfra & reliability: Firebase Auth (OTP, Apple, Google), EAS Build/TestFlight pipelines, and CI/CD hygiene across the stackCode quality: Participate in security audits and peer review within a small, high-trust engineering teamTech StackFrontend / Mobile: React Native + Expo, TypeScript, Firebase Auth (OTP, Apple, Google), EAS Build / TestFlight, Native iOS/Android context.Backend / AI: TypeScript (end-to-end), Anthropic API / Claude, Mastra (agent orchestration framework), LangChain (chains, tools, memory), Zeabur / cloud deployment, REST + Webhook integrations.You've Built and Run Agent Teams. Plural.This is not a role for someone who has experimented with LLMs on side projects. We're looking for engineers who have designed, shipped, and actively maintained multi-agent systems — and who understand what it takes to keep them reliable in production.Proven agent team ownership: You have built one or more autonomous agent teams from scratch — defined their scope, wired their tools, managed inter-agent communication, and own their continued operationSelf-validating mindset: You don't hand off agent output blindly. You act as the primary validation layer for the systems you build — designing evaluation criteria, catching failure modes, and iterating on agent behavior based on real output qualityCross-domain fluency: Your agents have touched multiple domains — not just one narrow use case. You can reason about agent behavior across booking logic, data quality, QA pipelines, code review, or content generation without needing a specialist in each areaMaintenance discipline: You have a track record of keeping agent systems healthy over time — prompt drift, tool failures, context window management, regression testing. Not just shipping and moving onFull-stack integration: You connect agent teams to real product surfaces — not just notebooks or internal tools. Your work shows up in APIs, mobile interfaces, or backend workflows that real users depend onRequirements5+ years of professional fullstack engineering, with meaningful production work in mobileStrong React Native track record — shipped apps, managed build pipelines, handled auth flowsTypeScript across the entire stack — mobile, backend, and agent tooling. This is non-negotiableHands-on with LLM APIs (Anthropic, OpenAI, or equivalent) — prompt engineering, tool/function calling, multi-turn context managementAI-augmented development: You use Claude Code, Codex, and similar agentic coding tools to achieve 10x engineering throughput. You know how to create, configure, and orchestrate coding agents — not just prompt them — and you treat them as force multipliers across your daily workflowMastra: Production experience with Mastra as an agent orchestration framework — workflows, tool definitions, agent memory, and inter-agent coordination patternsLangChain: Solid working knowledge — chains, retrieval, tool use, memory backends, and integration into live backend services. Not just tutorialsAbility to operate as a full engineering team member — not a specialist silo. You ship frontend, backend, and AI layers as needed, and you hold the full picture in your head simultaneouslyComfort in a lean startup environment: fast cycles, high ownership, minimal process overheadStrong written English. Arabic or German is a genuine plus given our marketsBonus PointsPrior work with GDS/NDC/travel supplier APIs (Amadeus, Sabre, PKfare, RateHawk)Experience building multi-agent AI systems or autonomous workflow orchestrationExperience with Voice AI agents (Ultravox, Vapi, ElevenLabs, or equivalen