Senior Software Systems Engineer

Why This Team? At Sabre, we’re transforming the technology behind the global travel industry. As part of our Customer Identity & Access Solutions team, you’ll work at the heart of our core infrastructure—building critical microservices, modernizing cloud session state, and securing web applications used by millions. Whether you're a Mid-Level looking to grow your system design skills and take on bigger technical challenges, or a Senior ready to drive architectural decisions and modernize enterprise security, this team offers the room, ownership, and intellectual challenges to elevate your career. You’ll join a collaborative, highly skilled, and friendly team that values clean code, TDD, and engineering excellence over quick hacks. What You’ll Do Build & Modernize: Design and develop scalable Java microservices and web applications powering core identity, authentication, authorization, and session state across Sabre's enterprise ecosystem.Elevate Engineering Standards: Practice Test-Driven Development (TDD), write clean, testable code, and lead/participate in constructive code reviews to maintain high quality.Own the Lifecycle: Drive feature delivery end-to-end—from initial design and automated testing to CI/CD pipelines, production deployment, and performance monitoring.Solve Scalability Challenges: Modernize legacy session management workflows into resilient, high-availability cloud-native architectures (GCP / Kubernetes).Collaborate & Mentor: Partner closely with product owners, security leads, site reliability engineers, and partner teams to refine requirements and share technical best practices across the team. Tech Stack You'll Work With Core & Frameworks: Java 8 / 17, Spring Framework (Spring Boot, Spring MVC/Core)Cloud & Infrastructure: Google Cloud Platform (GCP), Kubernetes, Docker, TomcatData & Security: SQL (Oracle), LDAP, OAuth/OIDC, Modern Identity ProtocolsDevOps & Automation: Jenkins, GitHub Actions, Maven, Git, BashTesting & Quality: JUnit, Mockito, Spock, Cucumber, TDD methodologies What We’re Looking For Whether you fit the Mid-Level or Senior track, we value a strong engineering foundation and a proactive mindset: Core Requirements (Mid & Senior) Java Proficiency: Solid experience developing core Java applications and RESTful microservices.Spring Ecosystem: Practical hands-on experience with Spring Boot and Spring Frameworks.Testing & Quality First: Demonstrated experience with TDD, unit/integration testing (JUnit, Mockito, etc.), and automated CI/CD pipelines.Data & Tooling: Comfort working with relational databases (SQL) and basic shell scripting (Bash).Communication & Mindset: Fluent English (written & verbal), strong troubleshooting skills, and a self-driven approach to solving tricky problems.Education: Bachelor’s degree in Computer Science, Software Engineering, or equivalent practical experience. What Makes You Stand Out For a Senior Role Experience designing and scaling cloud-native microservices (preferably on GCP with Kubernetes).Hands-on expertise with identity and access management (IAM), session state handling, high volume and high throughput applications, or enterprise security frameworks.A track record of mentoring junior engineers, driving architectural discussions, and improving CI/CD and deployment strategies. Ready to Shape the Future of Travel Tech? If you're eager to solve complex engineering problems in a supportive, tech-forward environment, we’d love to connect! Apply today and let's build what's next together. Work arrangements Hybrid working mode; 3 chosen days from the office in a weekFlexible working hours: Maintain your work-life balance by adjusting your working hours to your needs Paid time off Year-End-Break: enjoy additional fully paid days off during the last week of the yearPaid parental leave: Take up to 12 weeks off with pay after birth or adoption of a child. Sabre Global Paid Parental Leave runs concurrently with local leave policies.Paid volunteer time: take up to 4 days annually to give your time to a charitable organization of your choice Your money My Benefit platform/Multisport card: enjoy the benefit cafeteria system and use popular sport cardTax deduction: take the opportunity to claim deductible costs, reducing your income taxEmployee Capital Plans: profit from long-term saving scheme co-financed by Sabre and the State TreasuryBaby Bonus: benefit from one-time allowance on childbirth or adoption Say Thanks program: collect points on recognition program and transfer them to wide variety of gifts and services Health and wellness Luxmed VIP medical coverage: take care of yourself and your family with the extensive medical package with a broad range of additional servicesForeign travel insurance: feel safe going abroad with free Allianz insurance offered as part of our Lux Med packageEmployee Assistance Program: find help in free, confidential program with a certified counselorMindfulness & meditation apps: take care of your mental and physical healthLife insurance: sign up for free, high coverage life insurance program Career development Professional development: access to e-learning platforms as well as join Sabre live learning sessionsCertification and tuition reimbursementOur Communities: join one of our team member groups focused on sharing knowledge and best practices (Google Developers Group, Innovation Lab Community, Women in Technology, SOLVE!T and many more) And more Car and bike parking Fun & Relax zone in modern office: enjoy electronic tables to work, foosball, ping pong, pool table, swings, massage chairs and terraces to admire a panoramic view of Kraków. We have parents’ rooms as wellNo dress codeInnovation Lab: access Augmented Reality & Virtual Reality equipment, Robot construction kit, 3D printers and many moreAttractive Referral Bonus: earn $2500 USD for every hired referral