Lead Backend Engineer (Personalization)

Location: Hamburg or Berlin, Germany

Salary: From €85,000 yearly

Company

hirify.global is a European e-commerce company combining fashion and technology to create personalized online shopping experiences.

What you will do

• Take technical ownership of complex backend systems across Search, Recommendations, or Sorting from concept through production.
• Design and evolve high-throughput, low-latency services and the technical foundations of the Personalization area.
• Build and operate systems combining ML models, search and ranking algorithms, behavioral signals, and business logic.
• Make architectural decisions across team boundaries and establish standards for scalability, reliability, and maintainability.
• Collaborate with Data Scientists, Data Engineers, Analysts, and Product Managers to turn experimentation into product improvements.
• Mentor engineers, share expertise, and raise engineering standards across teams.

Requirements

• 7+ years of experience building scalable backend systems and APIs with a strong record of technical ownership.
• Recent experience with a typed programming language, ideally Node.js and TypeScript, or strong experience with Java, Go, or Kotlin.
• Deep understanding of backend architecture, distributed systems, APIs, data stores, and performance optimization.
• Strong algorithmic and analytical thinking with an interest in search, recommendations, ranking, or personalization.
• Experience combining backend engineering and ML, such as serving model scores, embeddings, or ML-driven features in production.
• Strong English communication skills are required.

Nice to have

• Technical background in Search, Recommender Systems, Ranking, or Personalization.
• Experience with Elasticsearch or OpenSearch, Redis or Valkey, high-throughput APIs, or performance-critical backend systems.
• Familiarity with ML-powered systems, LLMs, embeddings, vector search, or Learning-to-Rank.
• Experience with large-scale systems, AWS or GCP, BigQuery, dbt, or Dagster.
• Background in e-commerce, search, recommendations, advertising, or related relevance-focused domains.

Culture & Benefits

• Flat hierarchies, direct communication, pragmatic decisions, and clear ownership.
• Inclusive environment focused on acceptance, inclusion, and diverse perspectives.
• Team lunches, afterwork activities, company events, and informal opportunities to connect.
• Additional benefits are provided through the company benefits program.

Hiring process

• Apply online through the career page.
• The hiring team will follow up after reviewing the application.