Founding Backend Engineer

Pioneering Emotional Intelligence in AI

At Robyn AI, we’re not just building software; we’re crafting a new era of human-AI interaction. Our mission is to foster a more emotionally connected world by developing products that genuinely transform how people engage and find support. Robyn is the world’s first AI companion designed with deep emotional intelligence – a trusted mirror, a personal guide, an entirely new operating system for emotional well-being. We’re backed by visionary investors including M13, Google Maps co-founder Lars Rasmussen, Zoom/Canva seed investor Bill Tai, and x.ai co-founder Christian Szegedy, having successfully raised $5.5M to bring this vision to life.

Join Us as a Founding Backend Engineer

As our Founding Backend Engineer, you won’t just write code; you will architect and build the core engine powering Robyn’s groundbreaking emotional intelligence. You will be the technical architect behind intuitive conversations, evolving memory systems, real-time personalization, and seamless voice and chat interactions. This is a high-impact role where you will design, build, and ship fast, scalable, and emotionally aware systems from the ground up, working hand-in-hand with our iOS, Product, and cutting-edge AI teams.

Your Core Impact Areas

You will have significant ownership across critical areas of our backend infrastructure:

• Architecting & Migrating Core Services: Lead the transition from our initial C# / .NET Core backend to a robust, scalable Python / FastAPI architecture. Design modular systems ready for significant growth.
• Building High-Performance APIs: Develop and optimize secure, low-latency REST and GraphQL APIs crucial for a seamless user experience on our iOS application. Focus on resilience and observability.
• Integrating Advanced AI/ML Systems: Implement and manage pipelines using frameworks like LangChain, integrating cutting-edge LLMs (such as GPT-4o, Claude, Llama 3). Work with vector databases (like Redis Vector, Pinecone) for RAG, memory, and personalization features. Build robust wrappers for inference APIs (e.g., OpenAI, ElevenLabs) with critical failovers and caching strategies. Power our unique emotion and sentiment analysis engine.
• Cloud & Infrastructure Leadership: Own our AWS environment end-to-end, including deployment and orchestration using Docker, Kubernetes (EKS), and managing infrastructure-as-code with Terraform.
• Driving Operational Excellence: Establish and refine CI/CD pipelines using GitHub Actions. Implement comprehensive monitoring and logging solutions (Datadog, CloudWatch, Sentry). Ensure performance optimization (e.g., PostgreSQL indexing, Redis caching). Lead efforts towards SOC-2 readiness, ensuring security and compliance are built-in.
• Crafting Emotionally Intelligent Systems: Design backend logic that enables real-time adaptation to user emotional states. Build and evolve memory engines that leverage user embeddings and experience graphs to create deeply personal interactions, collaborating closely with AI and Product teams.

Our Tech Environment

You’ll be working hands-on with a modern and evolving stack:

• Backend: Python (FastAPI), legacy C# / .NET Core, PostgreSQL, Redis, GraphQL, REST, WebSockets.
• Infra: AWS (EC2, Lambda, S3, RDS, CloudFront, IAM, Route 53), Terraform, Docker, Kubernetes (EKS), GitHub Actions.
• Monitoring/Observability: Datadog, CloudWatch, Sentry.
• AI/ML: Leading LLMs (GPT-4o, Claude, Llama 3), LangChain, HuggingFace, Vector Databases (Redis Vector, Pinecone), Whisper, ElevenLabs.

What You Bring

We’re looking for a hands-on builder and strategic thinker who:

• Has 3+ years of experience in backend or full-stack development.
• Has successfully architected and shipped entire production backends at high-growth, early-stage startups – you know how to balance speed with building sustainable systems.
• Is comfortable navigating a legacy C# / .NET Core codebase short-term but is eager to lead the migration to a modern Python / FastAPI stack, with prior experience in system migrations.
• Has integrated and scaled LLM-based products in production, with bonus points for experience involving emotion, memory, or personalization layers.
• Possesses a strong foundation in systems thinking, prioritizing fast response times, clean abstractions, and building resilient infrastructure under load.
• Embodies the “zero-to-one” mindset – capable of holding the overall product vision and the technical implementation details simultaneously.
• Prefers the efficiency and impact of a small, high-performing team over large, bureaucratic structures.

(EU candidates preferred for time zone alignment).

Why Join Robyn AI?

Be part of something truly transformative at the intersection of AI and human connection:

• Shape and ship the world’s most emotionally intelligent AI product during a period of explosive growth.
• Work directly with a visionary founder (a Harvard-trained surgeon turned CEO) deeply committed to the mission.
• Join a team backed by elite investors with unparalleled experience in building world-changing companies (co-founders of Google Maps, x.ai, seed investors in Zoom/Canva, and more).
• Benefit from the unique opportunity of being an early team member – offering massive technical ownership, creative control, and direct impact on the product and culture.
• Thrive in our remote-first, async-friendly culture that prioritizes deep focus, emotional clarity, and sustainable productivity.

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