Senior Software Engineer (FlinkSQL)

Location: Remote, based in Europe; the role is listed in Ehningen, Baden-Württemberg, Germany. Some travel may be required, and participation in an on-call rotation is expected.

Company

IBM Software develops AI-powered, cloud-native, hybrid cloud, and data products for enterprise customers.

What you will do

• Implement and improve the Apache Flink SQL parser, logical planner, optimizer, syntax, built-in functions, and planner rules.
• Improve the correctness and performance of streaming SQL operators, including joins, aggregations, and changelog processing.
• Integrate Flink SQL with Kafka topics, Schema Registry schemas, data types, and Avro, Protobuf, and JSON formats.
• Develop features across the SQL surface, including user-defined functions, the Table API, and INFORMATION_SCHEMA.
• Investigate planner and semantic bugs, expand semantic test coverage, and deliver features through implementation, testing, and safe rollout.
• Build metrics, structured logging, dashboards, runbooks, and incident follow-ups while operating the service in production.

Requirements

• Bachelor’s degree and 2–3+ years of industry experience building backend services, data infrastructure, or distributed systems.
• Strong foundations in data structures, algorithms, concurrency, and distributed systems.
• Proficiency in Java or another JVM language such as Scala, with the ability to work in a large existing codebase.
• Solid understanding of SQL and relational concepts, with familiarity with databases, query engines, or stream processors.
• Experience operating services on at least one major public cloud: AWS, GCP, or Azure.
• Ability to deliver features end to end, participate in design discussions and code reviews, maintain high code quality, and join the on-call rotation.

Nice to have

• Experience with Apache Flink SQL, the Table API, Spark SQL, Trino, or another large-scale data processing system.
• Familiarity with query planners, optimizers, compiler construction, or Apache Calcite.
• Understanding of event time, watermarks, CDC handling, Apache Kafka, Schema Registry, Avro, or Protobuf.
• Contributions to open-source streaming, database, or distributed-systems projects.
• Master’s degree or experience with Kubernetes-based environments.

Culture & Benefits

• Work remotely from Europe with daily collaboration across Europe and North America.
• Collaborate with the Apache Flink open-source community.
• Access an environment focused on learning, continuous development, feedback, experimentation, and collaboration.
• Work on AI, cloud, data, and software products used by enterprise customers.