Senior Backend Engineer

Junior; New York (NY); On-site; USD 100,000 - 140,000; Full time

Benefits offered by this job

Competitive pay and equity

Private healthcare

Gym membership

In-office cook

Summers working in Greece by the beach

Job summary

Junior is hiring a Backend Engineer to help build and scale their AI-driven research platform. Located in New York, you will work closely with complex distributed systems, focusing on data flows and performance.

The ideal candidate should possess strong skills in Python and TypeScript, with a solid understanding of PostgreSQL. The role offers competitive pay, equity, and unique benefits like summers in Greece.

Qualifications

• Strong experience in backend projects from architecture to production.
• Excited to work 5 days a week in person in NYC.
• Experience with high-throughput LLM interactions and vector search.

Responsibilities

• Build and scale systems for the AI-driven research platform.
• Architect backend systems for high-performance interactions.
• Enhance database reliability and observability.

Skills

Python

TypeScript

PostgreSQL

Data modeling

System design

API development

Job description

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 ~43 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

• 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.

Benefits

• Competitive pay and equity.
• Private healthcare.
• 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 [e-mail] with your resume and a brief introduction. We can't wait to meet you!