Senior Java Software Engineer, GDS

About the role

KAYAK, part of Booking Holdings, is a travel search engine and is building its corporate travel solution, KAYAK for Business. Its Kaunas engineering team is growing and is looking for a Senior Java Backend Developer to design, build and own the systems that connect to global distribution systems (GDS) and airline content powering fares, availability, pricing and ticketing. The role involves shaping technical direction, tackling hard integration and performance problems and mentoring other engineers. At least 3 days per week must be worked from the Kaunas office.

Key responsibilities

• Lead the design and delivery of backend features for flight search, pricing and booking across GDS and other travel-supplier integrations.
• Own the reliability and performance of high-traffic services, diagnosing production issues and improving latency, throughput and cost per search.
• Evaluate the value of work before building and track success metrics after release.
• Build and evolve integrations with third-party APIs (SOAP/XML, REST and proprietary protocols), handling quirks, rate limits and failure modes.
• Act as a point of contact with partners on integration issues, investigating problems and following tickets to resolution.
• Contribute to technical decisions: write design documents, review architecture and code, and help set quality and testing standards.
• Mentor mid-level and junior engineers through code reviews, pairing and technical guidance, and work with product, QA and partner teams on scoping and rollout.
• Use AI coding tools as part of the day-to-day workflow.

Required profile

• Education in Computer Science or a related field, or equivalent practical experience.
• Significant hands-on experience with Java, including designing and operating production backend systems.
• Strong experience integrating with third-party systems and working directly with their providers.
• A track record of leading projects end to end and supporting the growth of other engineers.
• Fluent English and comfort in a hybrid model with at least three office days per week.

Required skills

• Spring framework and SQL databases.
• Bonus: Kubernetes, GDS platforms (Amadeus, Sabre, Travelport) or airline NDC/direct-connect APIs, airline domain knowledge, and familiarity with AI coding tools.

What we offer

• Salary of 3,330 to 6,660 EUR gross per month, plus significant yearly bonuses of about 10% of annual salary.
• Booking Holdings RSUs with possible yearly refreshes.
• Work from almost anywhere for up to 20 days per year, free lunch twice a week, and no-meeting Fridays.
• Career growth funds, e-learning access, health insurance, flexible sick time and extra support for sick leave and parental leave.
• Company-paid therapy sessions, HeadSpace subscription, paid volunteering time, a company-wide winter holiday week and internal communities.