Founding Backend ML Engineer

Job Description

Job Description

Founding Backend ML Engineer
Full-time | Hybrid | San Francisco, CA
Salary: $150K – $250K + 0.5%–2% Equity

We are seeking a Founding Backend ML Engineer to design, build, and scale the backend systems powering an AI platform that blends emotional intelligence with cutting-edge personalization. This role will put you at the heart of a small, high-performing team, giving you ownership over backend architecture, infrastructure, and AI integrations from the ground up.

What You’ll Do

1. Backend & Infrastructure Architecture

• Refactor a legacy backend (C# / .NET Core) into Python (FastAPI) with modular architecture for scalability.

• Build robust REST and GraphQL APIs consumed by iOS, optimized for latency, resilience, and observability.

• Deploy and orchestrate microservices on AWS (EKS) with Docker, Kubernetes, and Terraform.

• Own CI/CD pipelines, monitoring, logging, and incident response — full backend autonomy.

2. AI & ML Systems Integration

• Manage vector databases (Redis Vector, Pinecone) for retrieval-augmented generation, memory, and personalization.

• Build and maintain ML pipelines using LangChain, integrating LLMs (GPT-4o, Claude, Llama 3, etc.).

• Wrap inference APIs with caching, fallback, and routing logic.

• Power emotion and sentiment engines with classifiers and prompt orchestration.

3. Infra, DevOps & Data Engineering

• Manage the AWS stack: EC2, Lambda, S3, RDS, CloudFront, IAM, Route 53.

• Build infrastructure-as-code with Terraform and deploy pipelines via GitHub Actions.

• Optimize performance via Postgres indexing, Redis caching, and async pub/sub systems.

• Stand up observability tools (Datadog, CloudWatch) and prepare for SOC-2 compliance.

4. Emotional Intelligence & Personalization

• Architect systems that adapt to user emotions in real-time.

• Build evolving memory engines using user embeddings and experience graphs.

• Collaborate with product and AI teams to fine-tune emotional responses and journaling APIs.

What We’re Looking For

• 6–15 years of experience in backend or full-stack engineering.

• Proven track record building 0→1 products or teams in a startup environment.

• Deep knowledge of backend development, cloud infrastructure, and AI/ML integration.

• Passion for building systems that blend technology with emotional intelligence.

• Ability to work in a hybrid model from San Francisco.

Tech Stack

• Backend: Python (FastAPI), C# / .NET Core (legacy), PostgreSQL, Redis, GraphQL, REST, WebSockets

• Infra: AWS, Terraform, Docker, Kubernetes (EKS), GitHub Actions

• Monitoring: Datadog, CloudWatch, Sentry

• AI/ML: GPT-4o, Claude, LangChain, HuggingFace, Redis Vector, Pinecone, Whisper, ElevenLabs

Why Join

• Be the technical backbone of a mission-driven startup building products that drive deeper emotional connection.

• Significant equity ownership from day one.

• Direct impact on product strategy, technical decisions, and team growth.

• Opportunity to work on a mix of cutting-edge AI, scalable backend systems, and emotional intelligence personalization.