About Firsthand

Firsthand has built the first AI-powered Brand Agent platform, transforming the way marketers and publishers engage consumers through their own AI agents, anywhere online.

While most AI applications in marketing and advertising focus on back-office automation, the Firsthand Brand Agent Platform™ powers front-line consumer engagement. Operating across both owned properties and paid media, Firsthand's Brand Agents make a company’s expertise accessible in real time, adapting to consumers’ interests and guiding them towards the information they need to take action. Central to the platform is Lakebed™, the company’s AI-first data and knowledge rights management system that ensures brands retain full ownership and control of their expertise.

Firsthand is led by Jon Heller, Michael Rubenstein, and Wei Wei, whose previous ventures helped build the foundations of modern digital advertising. Backed by Radical Ventures, FirstMark Capital, Aperiam Ventures, and Crossbeam Venture Partners, Firsthand is shaping the future of AI-driven consumer engagement.

Firsthand is headquartered in NYC, with team members working together in-office three days a week.

About The Role

We're looking for a Senior Backend Engineer to architect and scale our AI platform's backend infrastructure.

As a Senior Backend Engineer, you'll be responsible for:

• Building scalable backend systems using Python and other technologies to support our AI-powered applications
• Designing and implementing multi-tenant architectures with strict data isolation, ensuring secure and performant access patterns across backend components
• Optimizing high-performance APIs that integrate with LLM workflows, vector search, and real-time AI processing pipelines
• Leading database architecture decisions, including schema design, query optimization, and migration strategies
• Mentoring junior engineers on best practices for async programming, database design, and production system reliability
  
  

• 5+ years of professional backend development experience with strong expertise in Python and modern web frameworks
• Deep expertise in Python with production experience building high-throughput APIs and background task processing
• Strong database skills in query optimization, schema design, and experience with vector databases
• Production experience with multi-tenant SaaS architectures, including data isolation patterns, tenant-aware query design, and scalability considerations
• Hands-on experience with caching strategies and distributed task queues
• Experience with cloud platforms (Google Cloud Platform preferred) and containerized deployments
• Excellent problem-solving skills with experience debugging production issues and optimizing system performance
• Self-driven and collaborative with experience mentoring team members and driving technical decisions in a fast-paced startup environment