Data Engineer (Apache Flink, ML Data Engineering)

TL;DR

Data Engineer (Apache Flink, ML Data Engineering): Build and maintain the data infrastructure that powers an adtech decision engine at massive scale, with an accent on real-time stream processing, feature/data pipelines, and low-latency data quality for ML systems. Focus on designing robust data architectures (including lakehouse/medallion concepts), eliminating ETL/pipeline bottlenecks, and bridging Data Science requirements into production-ready streaming and batch pipelines.

Location: Relocation support to Hamburg, Germany

Company

hirify.global builds rewarded advertising technology for mobile app growth and monetization, powered by its Playtime Arcade platform.

What you will do

• Build and maintain the infrastructure for ML at scale: feature store, data pipelines, data quality systems, and data architecture.
• Implement real-time data processing using Apache Flink for stateful stream processing and real-time feature computation.
• Identify and eliminate bottlenecks in complex ETL jobs across batch and streaming systems (including Kafka).
• Design layered data architectures using dbt and data lakehouse concepts for a 1PB+ behavioral data lake.
• Collaborate with Data Scientists to make online ML systems production-ready with low-latency requirements.
• Own data integrity in production via validation, monitoring, and governance processes.

Requirements

• 5+ years of data engineering experience on a modern stack, handling several TB/day and thousands of events per second.
• Hands-on experience with Apache Flink for stateful stream processing and real-time feature computation.
• Proven ability to optimize and troubleshoot high-volume ETL and streaming pipelines (e.g., Kafka).
• Strong data modeling and architecture skills using dbt and lakehouse concepts; familiarity with Medallion Architecture is a plus.
• Strong Java required; Go or Python is a plus.
• Experience with production data validation/monitoring/governance; Airflow, Kubeflow, AWS, Terraform, and Kubernetes are a strong plus.

Culture & Benefits

• Relocation support to Hamburg, Germany for candidates ready to join the team.
• Work on systems used by hundreds of millions of users and powering billions of decisions daily.
• Autonomy and fast iteration: ship solutions multiple times a day and learn from results.
• Direct collaboration across a diverse global team (40+ countries).
• Emphasis on ownership and quality, not just delivery.

Hiring process

• Submit your application with your most passionate personal project, desired salary, and earliest possible start date.
• Cover letter is not required.