Senior Backend Architect — Real-time IoT & Kafka (Kraków)

Kontakt.io; Kraków; Hybrid; PLN 212,404 - 297,366; Full time

Benefits offered by this job

Equity in Series C company

Private healthcare

Multisport card

Competitive salary

Job summary

Kontakt.io, based in Kraków, is seeking an experienced backend engineer with extensive knowledge of Java and Kafka. You will design and maintain integration systems that handle real-time BLE and IoT data while ensuring top-level performance and documentation standards.

This role requires substantial backend experience, strong collaboration skills, and the ability to maintain high engineering standards in a dynamic environment, integrated within a tech-oriented culture. A competitive salary and stock options are part of the offer.

Qualifications

• 7+ years of backend software engineering experience, especially with Java and Spring Boot.
• Deep understanding of Apache Kafka operation and design principles.
• Experience in developing real-time, event-driven systems in a SaaS environment.

Responsibilities

• Design and maintain services that process real-time BLE and IoT telemetry.
• Build and maintain integrations with third-party systems.
• Drive architectural decisions and enforce documentation standards.

Skills

Backend software engineering

Java (Spring Boot)

Apache Kafka

Database fluency (MongoDB, PostgreSQL, Redis)

AWS experience (EKS, Kinesis, S3)

English communication

Tools

Terraform

Helm

Testcontainers

Job description

Kontakt.io, based in Kraków, is seeking an experienced backend engineer with extensive knowledge of Java and Kafka. You will design and maintain integration systems that handle real-time BLE and IoT data while ensuring top-level performance and documentation standards.

This role requires substantial backend experience, strong collaboration skills, and the ability to maintain high engineering standards in a dynamic environment, integrated within a tech-oriented culture. A competitive salary and stock options are part of the offer.