Senior/Staff Backend Engineer – Java (Remote – Poland)

About the role

As a Backend Engineer at Oscilar you will design, build, and maintain the core infrastructure that powers our AI Risk Decisioning™ SaaS platform. You will work closely with product, frontend, and QA teams to deliver highly reliable, low‑latency, and scalable services for global enterprise clients.

Key responsibilities

• Design and develop scalable, high‑performance backend services using Java and AWS.
• Collaborate with product, frontend, and QA to define technical requirements and ensure smooth integration.
• Optimize existing services for performance, reliability, and maintainability.
• Identify and resolve system bottlenecks, ensuring optimal resource utilization.
• Implement best practices for code quality, testing, and CI/CD pipelines.
• Monitor service health proactively and mitigate potential issues.
• Provide technical guidance and mentorship to junior engineers.

Required profile

• Bachelor’s or Master’s degree in Computer Science, Software Engineering, or a related field.
• 5+ years of backend development experience focused on Java and AWS.
• Proven experience building low‑latency, high‑scale services in distributed environments.
• Strong knowledge of microservices, Docker, Kubernetes, Kafka, and Clickhouse.
• Familiarity with RESTful API design and security best practices.
• Experience with CI/CD tools (Jenkins, Git, Maven, Gradle) and agile methodologies.
• Excellent problem‑solving skills and strong written and verbal communication.

Required skills

• Java
• AWS
• Docker
• Kubernetes
• Kafka
• Clickhouse
• RESTful API design
• Security best practices
• CI/CD (Jenkins, Git, Maven, Gradle)
• Microservices architecture
• Agile development

What we offer

• Competitive salary and equity packages, including a 401k.
• Remote‑first culture – work from anywhere.
• 100% employer‑covered health, dental, and vision insurance (US top‑tier plan for employee and dependents).
• Unlimited PTO policy.
• AI‑first company with >50% engineering and product focus.
• Family‑friendly environment with regular team events and offsites.
• Extensive learning and professional development opportunities.
• Impactful work protecting online transactions and making the internet safer.