Senior Staff Software Engineer
Kontakt.io4 months ago
Kraków, PolandStaff+
Responsibilities
- Design, build, and maintain Java/Spring and Kafka Streams services processing real-time BLE and IoT telemetry at scale.
- Own integrations with Cisco Spaces, Aruba, and other third-party location platforms from protocol understanding through production reliability.
- Build egress pipelines delivering location and event data through REST, gRPC, and WebSocket interfaces.
- Drive architectural decisions, sequencing, documentation, and engineering standards for a currently under-documented domain.
- Use AI tools for code generation, debugging, documentation, and prototype acceleration.
- Define testing standards with Testcontainers and CI pipelines using Jenkins and GitHub Actions.
- Instrument services with Prometheus and Micrometer and create Grafana dashboards for operational visibility.
- Collaborate with Data Platform and SRE teams on Kafka topology, state stores, and infrastructure ownership.
- Mentor engineers through code reviews, design sessions, and feedback.
Requirements
- 7+ years of backend software engineering experience with strong production Java experience.
- Deep hands-on Apache Kafka expertise, including Streams, state stores, topology design, and operational behavior.
- Experience building real-time, event-driven distributed systems in multi-tenant SaaS environments.
- Fluency with MongoDB, PostgreSQL, and Redis and the ability to select appropriate databases.
- Hands-on AWS experience with EKS, Kinesis, and S3, plus comfort with Terraform and Helm.
- A track record of improving messy or under-documented technical domains.
- Ability to work directly with product and business stakeholders and translate business requirements into engineering decisions.
- Clear written and verbal English communication skills.
- Must be based in or willing to relocate to Kraków, Poland.
- Preferred qualifications include Kotlin, IoT or BLE telemetry experience, Go or Python for tooling and automation, AsyncAPI, Drools, OAuth2, Keycloak, and experience in a high-growth Series B/C product company.
Benefits
- Equity in a Series C company with a clear growth trajectory.
- Private healthcare, a Multisport card, and a standard benefits package.
- Hybrid work from the Kraków office with at least two days in the office.
- Competitive salary benchmarked against the market, with no specific base-pay amount stated.
- Opportunity to work on a significant real-time IoT platform and technical challenge rather than a maintenance codebase.
Tech Stack
Apache KafkaAWSGitHub ActionsGoGrafanagRPCHelmJavaJenkinsKotlinMongoDBPostgreSQLPrometheusPythonRedisSpring BootTerraform
Categories