Senior Backend Engineer
👶 About Junior
We're building cutting-edge LLM-powered tools that supercharge investment research for the world's most demanding deal teams. Our clients include several of the top 10 global private equity firms, Big 4 professional services firms, and leading consulting practices: organisations responsible for deploying billions of dollars annually.
We're a profitable, bootstrapped company with a growing team of ~28 people based in London and New York. We 10x'd our revenue in 2025 and are on track to grow 2-3x again this year. Junior saves clients an average of 10 hours per week, and we're expanding fast into new verticals including investment banking, hedge funds, and research firms.
💡 Role Description
As a Backend Engineer, you’ll help build and scale the systems that power our AI-driven research platform. This is a systems-level role - ideal for engineers who love thinking about data flows, orchestration, and performance across complex distributed systems.
You'll have the unique opportunity to:
Ship quickly
Architect and scale backend systems that support high-throughput LLM interactions, vector search, and multi-agent orchestration.
Stitch together AI infrastructure across model providers, data stores, and internal APIs to create cohesive, performant systems.
Own reliability and observability, helping us evolve our database (Postgres / ClickHouse) and job orchestration systems.
Prototype new backend capabilities (retrieval pipelines, caching layers, async task queues) that let us build faster and smarter.
Shape our engineering culture
🔥 About You
We're looking for product-minded backend engineers who:
Based in NYC, ***we are 5 days a week in person
Are excited by the intersection of AI infrastructure and systems design
Have experience leading projects end-to-end
Are eager to contribute to product decisions
Are proficient in our tech stack: Next.js, TypeScript, PostgreSQL
Feel like you are never building fast enough
Bonus points for experience working on:
Retrieval/embeddings/prompt orchestration
Built internal infrastructure / dev tools @ startups
🌵 Benefits
All the usual benefits (competitive pay and equity, private healthcare etc). Unusual benefits:
Gym membership
In-office cook
Summers working in Greece by the beach
📩 How to Apply
If you're excited about the opportunity to drive innovation at Junior, we'd love to hear from you! Email us at careers@myjunior.ai with your resume and a brief introduction. We can't wait to meet you! 🙌