Senior Software Engineer - AI First, Full Stack

About the role

Senior Software Engineer - AI Platform Custom AI Solutions | Remote (Brazil) | Contract Engagement About the Role We are looking for a Senior Software Engineer to engage directly with our CTO and engineering leadership as a dedicated platform engineer on VoxaCor™ and BridgeNode™. This is not a staff augmentation role - you will have real ownership across architecture decisions, feature development, and platform reliability. VoxaCor™ is our AI voice and SMS platform built for high-volume, real-time communication. BridgeNode™ is the open-source AI conversation framework that powers it - every product CAIS builds runs on it. You will own significant surface area across both - from AI agent orchestration and real-time voice pipelines to frontend interfaces and infrastructure. AI-first development is core to how we build - if you haven't shipped production AI systems, this role isn't for you. This is a contract engagement. Applicants must have a registered legal entity in Brazil to contract through. This is a firm requirement and is not negotiable. Key Responsibilities Build and maintain real-time AI voice pipeline components: STT, TTS, LLM orchestration, and telephony integration Develop multi-tenant SaaS platform features across web, voice, and SMS channels Implement AI agent workflows using Mastra orchestration and Anthropic/Gemini LLM integrations Design and build backend services, APIs, and data models supporting high-volume production workloads Develop frontend interfaces and progressive web app (PWA) features in React Build platform tooling, admin interfaces, and partner-facing configuration systems Contribute to BridgeNode™ open-source framework and VoxaCor™ proprietary feature layers Tech Stack Backend: Node.js, TypeScript, PostgreSQL, Docker Frontend: React 19, TypeScript, Tailwind CSS, shadcn/ui, PWA Voice & Telephony: Telnyx, Deepgram (STT/TTS), WebRTC, SIP AI / LLM: Anthropic Claude, Google Gemini, Mastra orchestration Infrastructure: Azure, GitHub Actions CI/CD, multi-tenant architecture Compensation Structure: Paid twice monthly in USD for work performed On-Target Earnings: $44K-$66K USD - depending on experience Qualifications 5+ years of full-stack engineering experience with TypeScript/Node.js and React Production experience building and shipping AI-powered applications - not just prototypes Hands-on experience with LLM APIs (Anthropic, OpenAI, Gemini, or equivalent) and agent orchestration Real-time systems experience: WebSockets, streaming APIs, or telephony/voice pipelines Strong database and API design fundamentals with PostgreSQL Comfortable working in a multi-tenant SaaS architecture Professional English proficiency - written and verbal communication must be clear, accurate, and effective for async collaboration with a US-based team Able to work independently, manage your own priorities, and communicate proactively in English Available to overlap with US Mountain/Pacific business hours for team collaboration Registered legal entity in Brazil - required for contract engagement (not negotiable) Strong Pluses Experience deploying or self-hosting open-source LLMs in private or air-gapped infrastructure environments Prior work in voice AI, telephony platforms, or real-time audio pipelines Open-source contributions, particularly to frameworks or developer tooling Experience with Mastra, Pipecat, or similar AI agent orchestration frameworks Background in transportation, logistics, or dispatch software ecosystems What We're Looking For The ideal candidate is an experienced, self-directed engineer who defaults to building. You don't need hand-holding - you read the requirements, ask the right questions, and ship. You're excited about AI not as a buzzword but because you've worked in the stack and understand what it takes to run these systems in production. You want a role where your work matters and your decisions have real impact. Not a Fit If You don't have direct experience shipping AI systems to production You're looking for a short-term engagement You don't have a registered Brazilian entity to contract through You need heavy management oversight to stay productive Your English is not sufficient for async written collaboration Originally posted on Himalayas

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