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Salary: EUR 3,330 - 6,660 / monthly
KAYAK, part of Booking Holdings, is a leading travel search engine processing billions of queries across global metasearch brands including momondo, Cheapflights, and HotelsCombined. This Senior Front End Software Engineer role focuses on the Retention domain, requiring end-to-end ownership of complex frontend features from scoping through deployment and monitoring.
You will design and build sophisticated user-facing features while maintaining high code quality standards. Key responsibilities include leading technical design discussions for your team's domain, identifying and proactively addressing technical debt and performance issues, and mentoring less-experienced engineers through code reviews and pair programming. You'll collaborate closely with product managers and designers to clarify requirements and surface risks early, ensuring features meet real user and business needs. Active participation in agile ceremonies—sprint planning, backlog refinement, retrospectives, and demos—is expected to maintain predictable team delivery. You'll contribute to improving team processes, tooling, and engineering standards, and use AI-assisted development tools responsibly to enhance productivity and code quality.
The role is based in the Kaunas office with a hybrid model requiring at least three office days per week. You'll have flexibility to work remotely up to 20 days per year.
REQUIREMENTS:
- Demonstrated experience independently designing and delivering complex frontend features in production environments (equivalent experience, transferable skills, and non-traditional career paths welcome)
- Strong proficiency in JavaScript and TypeScript with solid experience building user interfaces using modern component-based frameworks (React or similar)
- Good understanding of how frontend systems interact with APIs and backend services; experience debugging and optimizing across that boundary
- Experience writing and maintaining automated tests (unit, integration, or end-to-end) with genuine care for code quality and long-term maintainability
- Ability to communicate technical ideas clearly in design documents, code reviews, and team discussions; ability to give and receive feedback constructively
- Track record of taking ownership through to completion: surfacing blockers early, following through without prompting, caring about outcomes
- Fluent English communication skills
- Comfort working in agile team environments with iterative delivery, regular collaboration, and shared accountability
- Comfort with hybrid work model, minimum three office days per week
PREFERRED QUALIFICATIONS:
- Experience with advertising technology, user engagement features, or revenue-impacting frontend products
- Familiarity with A/B experimentation frameworks or feature flagging systems
- Experience mentoring or supporting engineer growth
