Senior Kafka Developer

INFOZEN INC; Polska; Hybrid; PLN 544,000 - 816,000; Full time

Job summary

INFOZEN INC is seeking a Senior Kafka Developer to design, develop, test, deploy, and support secure, scalable event-driven applications on an enterprise Apache Kafka platform across on-premises Linux (RHEL 9) and cloud environments.

The role requires 10+ years in software development, including 5+ years hands-on experience with Kafka; you will build producers, consumers, Kafka Streams apps, and integrations with Kafka Connect, Avro/Protobuf schemas, and strong security and CI/CD practices.

Qualifications

• 10+ years of enterprise software development experience.
• 5+ years hands-on Apache Kafka development.
• Strong experience with Java, Spring Boot, REST APIs, microservices, and event-driven architecture.
• Deep understanding of Kafka producers, consumers, partitions, offsets, and delivery guarantees.

Responsibilities

• Develop Java, Spring Boot, and Spring for Apache Kafka producers and consumers, microservices, and Kafka Connect integrations.
• Design topics, partitions, message keys, consumer groups, offsets, retries, and idempotency.

Skills

Java

Spring Boot

Spring Kafka

REST APIs

Microservices

Event-driven

Tools

Kafka Streams

Kafka Connect

Schema Registry

Avro

Protobuf

Job description

Senior Kafka Developer

Location: Remote – U.S.

Employment Type: W2

Experience: 10+ years overall, with 5+ years of hands‑on Apache Kafka development

Job Summary

We are seeking a Senior Kafka Developer to design, develop, test, deploy, and support secure, resilient, event-driven applications and integrations on an enterprise Apache Kafka platform across on-premises RHEL 9, AWS, and Azure environments.

Key Responsibilities

• Develop Java, Spring Boot, and Spring for Apache Kafka producers, consumers, microservices, Kafka Streams applications, and Kafka Connect integrations.
• Design Kafka topics, partitions, message keys, consumer groups, offsets, retries/DLTs, idempotency, and delivery semantics.
• Implement schemas and data contracts using Avro, JSON Schema, Protobuf, and Schema Registry.
• Implement Kafka security using TLS/mTLS, SASL/SCRAM, ACLs, PKI, certificates, keystores, truststores, and secrets management.
• Support and troubleshoot Kafka connectivity across on-premises, AWS, and Azure, including network, authentication, certificate, latency, and replication issues.
• Develop automated testing and deployments using Git, CI/CD, Terraform, Ansible, and Shell scripting.
• Implement monitoring, logging, tracing, health checks, consumer-lag monitoring, and alerting.
• Participate in architecture/code reviews, performance tuning, production support, incident analysis, documentation, and knowledge transfer.

Required Qualifications

• 7+ years of enterprise software development experience, including 4+ years of hands‑on Apache Kafka development.
• Strong experience with Java, Spring Boot, Spring Kafka, REST APIs, microservices, and event-driven architecture.
• Deep understanding of Kafka producers, consumers, partitioning, replication, offsets, rebalancing, serialization, transactions, idempotence, and delivery guarantees.
• Hands‑on experience with Kafka Streams, Kafka Connect, Schema Registry, Avro/JSON Schema/Protobuf, and schema evolution.
• Strong knowledge of Kafka security, Linux/RHEL, Git, Maven/Gradle, CI/CD, automated testing, monitoring, performance tuning, and production support.

Preferred Qualifications

• Experience with Kafka across on-premises, AWS, and Azure environments.
• Exposure to KRaft, MirrorMaker 2, disaster recovery, replication, and cross-cluster patterns.
• Experience with Prometheus, Grafana, Splunk, OpenTelemetry, Kong, or equivalent technologies.
• Experience with Confluent Platform/Cloud, managed connectors, RBAC, Cluster Linking, ksqlDB, or Flink.
• Relevant Kafka, Java, Cloud, or DevOps certifications are a plus.

This is a remote position.