Senior Backend Engineer - Ranking Systems (all genders)

SmartRecruiters, Inc.; Hamburg, Berlin; Vor Ort; EUR 70.000 - 85.000; Vollzeit

Zusammenfassung

ABOUT YOU is one of Europe’s fastest growing e-commerce companies, based in Hamburg and Berlin. You will shape how millions of users see products by blending ML model outputs with business logic and own our high-throughput ranking engine, ensuring fast, deterministic, and fair product sorting.

You’ll design reliable batch write pipelines from BigQuery into Postgres/MySQL, and develop low-latency APIs with Fastify and Node.js/TypeScript while collaborating with data engineers, product managers,

Qualifikationen

• 5+ years of backend experience with Node.js/TypeScript.
• Strong SQL knowledge with Postgres/MySQL.
• Interest in ranking problems and ownership of product metrics.
• Clear English communication and pragmatic mindset.

Aufgaben

• Shape product ranking by blending ML outputs with business logic.
• Own the high-throughput ranking engine (Spotsetter) for fast, deterministic, fair sorting.
• Design batch write pipelines from BigQuery to Postgres/MySQL.
• Develop low-latency APIs using Fastify and Node.js/TypeScript.
• Collaborate with data engineers, product managers, and commercial teams for data-driven decisions.
• Maintain clean codebase with architectural collaboration.

Kenntnisse

Backend engineering

Node.js/TypeScript

SQL knowledge

Ranking algorithms

English communication

Tools

BullMQ

Redis

AWS CDK

GCP/BigQuery

Postgres

MySQL

Jobbeschreibung

• Full-time
• Compensation: EUR 70,000 - EUR 85,000 - yearly

Company Description

ABOUT YOU is one of Europe’s fastest growing e-commerce companies. Based in Hamburg and Berlin, we operate at the intersection of fashion and technology. Our mission is to rethink online shopping and make it personal and seamless. This takes more than good ideas. It takes people who take initiative and challenge the status quo. We believe in flat hierarchies, direct communication, and pragmatic decisions. No long approval chains. Just ownership, trust, and clear responsibility. We work hard, but we also believe in enjoying the ride together - over team lunches, afterwork drinks, company events, or a quick coffee in between meetings. If this sounds like you, ABOUT YOU could be the right place to bring in your perspective.

Job Description

• Shape how millions of users see products by blending ML model outputs with business logic (like campaign boosts or sponsored items)
• Build and own our high-throughput ranking engine ("Spotsetter") to ensure fast, deterministic, and fair product sorting
• Design reliable batch write pipelines that stream data from BigQuery straight into high-performance relational stores like Postgres and MySQL
• Develop low-latency serving APIs with Fastify and Node.js/TypeScript
• Work closely with data engineers, product managers, and commercial teams to make data-driven ranking decisions
• Architectural freedom: collaborate with our Tech Lead, bring in your own ideas, and keep our codebase clean

Qualifications

• You love digging into ranking problems, taking deep ownership of a product, and seeing your changes move real business metrics
• 5+ years of experience with backend systems (Node.js/TypeScript preferred, but we welcome fast learners from Java, Go, or Kotlin)
• Strong hands-on SQL knowledge (Postgres/MySQL schema design, query optimization, and batch operations beyond basic ORMs)
• Good algorithmic intuition for sorted data, deduplication, latency trade-offs, and constraint logic
• You're excited to bridge backend engineering and ML by serving model scores or ranking data in live systems
• Clear communication skills in English and a pragmatic, solution-oriented mindset

Nice to Have

• Experience with job queues (BullMQ, Redis) or batch processing pipelines
• Exposure to cloud tooling (AWS Step Functions, CDK, GCP/BigQuery)
• Background in e-commerce, sponsored products, or ad-tech systems
• Curiosity about learning-to-rank algorithms

Your perks at a glance: Visit our benefits page .
A Place Where You Can Be You
We take it as our responsibility to create an environment where everyone feels welcome, exactly as they are.
Different backgrounds and perspectives make us stronger and shape our culture in ways that matter.
What we stand for internally, we stand for as a brand: acceptance, inclusion, and a fairer approach to fashion.