Senior Backend Engineer

Junior is building the AI operating system for investment research. Our software helps private equity firms, consultants and financial institutions complete high-stakes research workflows dramatically faster - from diligence and memo writing to market mapping, research synthesis and strategic analysis.

We’re trusted by several of the world’s top private equity firms, Big Four consultancies and leading financial institutions.

• Bootstrapped and profitable

• $25M+ in revenue after growing 10x last year

• 60+ people across the company

• 23-person engineering team, growing to 40+ this year

• Core stack: TypeScript, Next.js and PostgreSQL

You’d be joining early enough to shape the product, engineering culture and company, but with enough traction that everything you build lands immediately in front of demanding, paying customers.

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

We're looking for product-minded backend engineers who:

• Are based in NYC and excited to work 5 days a week in person

• Are excited by the intersection of AI infrastructure, financial systems, and backend engineering

• Have experience owning backend projects end-to-end — from architecture through to production

• Are strong in Python and TypeScript

• Have worked with PostgreSQL and care about data modelling, reliability, and system design

• Are comfortable building APIs, internal tools, workflows, and infrastructure that support real customers

• Are eager to contribute to product decisions, not just execute tickets

• Feel like you are never building fast enough

Bonus points for experience working on:

• Billing, payments, usage-based pricing, or financial workflows

• Internal infrastructure / dev tools at startups

• Data pipelines, workflow orchestration, or event-driven systems

• Retrieval, embeddings, or prompt orchestration

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

If you're excited about the opportunity to drive innovation at Junior, we'd love to hear from you! Email us at [email protected] with your resume and a brief introduction. We can't wait to meet you! 🙌