Senior Software Engineer, Backend (AI)

What You'll Do

• Design and Scale Backend Services: Build and maintain scalable backend services and APIs that power AI-driven features, writing production code primarily in Java, and Python.
• Own Cloud Infrastructure: Define, deploy, and manage AI infrastructure using Terraform on a major cloud platform (AWS). Scale container-based solutions while ensuring reliability and performance.
• Build Evaluation Pipelines: Create robust frameworks to evaluate AI system quality and continuously improve model performance.
• Optimize for Cost, Latency, and Performance: Make pragmatic, business-aware decisions about the tradeoffs between model quality, response time, and infrastructure cost when working with managed AI services.
• Integrate Across the Stack: Collaborate with core engineering by occasionally working in TypeScript (Node.js) to connect AI features into Posh's main application.
• Support Agent Architecture: Build the backend systems and data flows that power our multi-step, autonomous AI workflows, ensuring they are reliable, observable, and scalable.

What We're Looking For

• 3 to 6+ years of backend or full-stack engineering experience, with a track record of shipping high-quality, scalable systems in fast-paced environments.
• Deep expertise in Python and its ecosystem for web services and data processing.
• Strong experience with Infrastructure as Code (Terraform), a major cloud platform (GCP, AWS, or Azure), and deploying containerized applications.
• Comfort operating in a 0→1 environment where you'll help define new patterns and practices for AI-native product development.

Bonus Points

• Experience with managed AI services (Vertex AI, AWS Bedrock, etc.), working with LLMs in production, or building evaluation frameworks (RAGAs, LangSmith, DeepEval).
• Familiarity with agentic frameworks (LangGraph, CrewAI, Strands) or multi-agent system design.
• Background in MLOps, data engineering, or experience at consumer, marketplace, or event-driven platforms.