---
title: 'Senior Software Engineer, K4B at KAYAK'
canonical: 'https://feeny.ai/job/senior-software-engineer-k4b-kayak-berlin-9b4jayma5t79'
type: 'job'
last_seen: '2026-10-17'
---

# Senior Software Engineer, K4B at KAYAK

- **Company:** KAYAK
- **Location:** Berlin, Germany
- **Employment:** full-time
- **Work type:** hybrid
- **Posted:** 2026-10-12
- **Last confirmed live:** 2026-10-17
- **Apply:** https://jobs.ashbyhq.com/kayak/5ee0d4cd-0d78-414c-a3fa-e467287a6027

## Job description

KAYAK, part of Booking Holdings (NASDAQ: BKNG), is the world's leading travel search engine. With billions of queries across our platforms, we help people find their perfect flight, stay, rental car and vacation package. We're also transforming business travel with a new corporate travel solution, KAYAK for Business. As an employee of KAYAK, you will be part of a travel company that operates a portfolio of global metasearch brands including momondo, Cheapflights and HotelsCombined, among others. From start-up to industry leader, innovation is at our core and every employee has an opportunity to make their mark. Our focus is on building the best travel search engine to make it easier for everyone to experience the world. We are looking for a strong Java backend developer to implement new features and maintain KAYAK’s world-leading search and booking technology. We integrate with over 200 travel partners and link to over 500,000 hotels and 550 airlines. You will be an essential part of a high powered team that keeps all of this running smoothly – helping millions of people find the best hotels and the best ways to fly from A to B every day! In this role you will be expected to work from our Berlin office at least 3 days per week.

In this role, you will:

- Optimize search and booking logic to handle the demands of greatest global corporate clients
- Build and maintain high-performance integrations with third-party APIs (airlines, hotel and rentalcars providers)
- Take full ownership of your designs: from initial concept to deployment while maintaining high standards for code quality and performance
- Participate in code reviews and architectural steering to ensure the K4B project remains modular and reusable as KAYAK expands its enterprise footprint

Please apply if you have:

- Bachelor’s degree or higher in Computer Science or related field
- 6+ years of experience in JAVA
- Hands-on experience with the Spring ecosystem (Spring/Spring Boot) and working knowledge of relational (SQL) and NoSQL databases (e.g., PostgreSQL, MySQL, Redis).
- Strong English communication skills
- Ability to design and implement engineering initiatives with minimal guidance
- Prior experience in the travel domain is beneficial — familiarity with airline distribution and standards (GDS such as Amadeus/Sabre/Travelport, NDC) and their integration with booking/reservation systems.
- Experience with B2B systems or identity/HR integrations is beneficial — e.g., SCIM, SAML/OAuth, SSO, user provisioning/deprovisioning, and connecting HRIS/IDP platforms (Workday, Okta, Active Directory) to product services.

Benefits and Perks:

- Work from (almost) anywhere for up to 20 days per year
- Focus on mental health and well-being:
- Company-paid therapy sessions through SpringHealth
- Company-paid subscription to HeadSpace
- Company-wide week off a year - the whole team fully recharges (and returns without a pile-up of work!)
- No meeting Fridays
- Paid parental leave
- Paid volunteer time
- Focus on your career growth:
- Development Dollars
- Leadership development
- Access to thousands of on-demand e-learnings
- Travel Discounts
- Employee Resource Groups
- 6 weeks paid vacation + a day off for your birthday
- Free lunch 2 days per week
- Pension plan contributions
- Public transportation subsidies
- Bike leasing program
- Monthly social events, Thursday happy hours, sports teams
- An awesome office in Friedrichshain, Berlin

Inclusion At KAYAK, we want everyone to have the space to grow, share ideas and do great work. That’s why we’re focused on hiring the best talent from all walks of life and experiences, supporting them well and making sure no one feels like they have to fit a mold to belong here. Need any adjustments for the interview, application or on the job? No problem - just give us a heads-up. We’ve got you.

## #LI-AS1

## About KAYAK

## Company Overview
- **One-liner**: KAYAK is the world’s leading travel metasearch engine, enabling travelers to compare flights, hotels, rental cars, and vacation packages from hundreds of sites in one place.
- **Entity Type**: Private (subsidiary of Booking Holdings Inc., NASDAQ: BKNG)
- **Headquarters**: Stamford, Connecticut, USA (with 15 international offices)
- **Founded**: 2004
- **Founders**: Steve Hafner (former CEO until February 2026) and Paul English

## Core Business
- **Primary industry/industries**: Online travel, travel technology, metasearch.
- **Target customers**: B2C (leisure and business travelers) and B2B (travel providers, advertisers, and corporate clients via KAYAK for Business).
- **Mission or purpose statement**: To help travelers make confident travel decisions by providing transparent, comprehensive search results that put control back in their hands. KAYAK believes “travel makes the world better.”

## Products & Services
- **KAYAK Metasearch**: Core product allowing comparison of flights, hotels, rental cars, and vacation packages from hundreds of travel sites.
- **KAYAK for Business (K4B)**: Free corporate travel solution for business travelers.
- **KAYAK Mobile App**: iOS and Android app offering seamless travel planning, price forecasts, price alerts, trip management, and AI-powered search.
- **KAYAK.ai**: AI-powered travel assistant providing personalized tips, live pricing, and conversational booking.
- **Explore Tool**: Inspires spontaneous travel by showing destinations within a chosen budget.
- **Trips**: Personal travel assistant for organizing, managing, and sharing itineraries with real-time flight status.
- **Price Forecast & Alerts**: Predicts price trends and notifies users of changes for flights, hotels, and car rentals.
- **KAYAK for Partners & Advertisers**: Commission-based and advertising revenue models.

## Market Standing
- **Valuation/Market Cap**: Not publicly disclosed as a subsidiary; parent Booking Holdings has a market cap of ~$150+ billion (as of mid-2025).
- **Key Metric**: Processes billions of searches annually; 800+ team members; 60+ international sites in 25+ languages.
- **Notable Investors/Partners**: Owned by Booking Holdings, Inc. (NASDAQ: BKNG), which acquired KAYAK in 2013. Partners with hundreds of airlines, hotels, online travel agencies, and car rental companies.
- **Growth Signals**: 
  - Named #1 Best Airfare Search Site by Frommer’s (2024, 2025).
  - Won World’s Best Flight & Hotel Comparison Website at World Travel Tech Awards (2022–2024).
  - Recognized by Statista & COMPUTER BILD as a Top Online Platform 2025.
  - First mainstream travel company to introduce AI-powered conversational search (KAYAK AI Mode).
  - Expanded portfolio of 7 travel search brands globally.

## Competitive Advantages
- **First-mover in travel metasearch**: Pioneered the concept in 2004, creating a trusted, comprehensive comparison platform.
- **Unbiased results**: Displays fares from all major providers without favoritism, clearly labeling booking sources.
- **Massive data advantage**: Processes billions of searches, enabling powerful AI/ML tools like Price Forecast and AI Mode.
- **Global brand portfolio**: Manages 7 brands (KAYAK, SWOODOO, checkfelix, momondo, Cheapflights, Mundi, HotelsCombined) with a global footprint.
- **Strong financial backing**: Part of Booking Holdings, providing stability and resources for innovation.
- **High trust & recognition**: Consistently ranked #1 by leading travel publications and awards.

## Strategic Focus
- **AI & personalization**: Leading with AI-powered search and conversational planning to improve user experience.
- **Expanding corporate travel**: Growing KAYAK for Business as a free, self-service corporate travel tool.
- **Global scale**: Continuing to expand international sites and language support.
- **Innovation in search tools**: Developing new features like Price Forecast, Explore, and real-time trip management.
- **Maintaining transparency**: Strengthening trust through clear labeling and fair marketplace practices.

## Why Work Here
- **Culture**: Mission-driven, data-obsessed team of 800+ passionate about travel technology; emphasis on career growth, skill development, and individual learning.
- **Work policy**: Hybrid model – team members work from the office three days a week, with flexibility to come in more often. Some roles are fully remote (US-based).
- **Perks**: Part of a global network including OpenTable and a portfolio of travel metasearch brands; employee-resource groups for under-represented communities; global equal-pay policy.
- **Engineering culture**: Strong focus on data, AI, and scalable systems (billions of queries); tech stack includes modern Java, frontend frameworks, and ETL tools.
- **Global opportunities**: 15 international offices with opportunities to work across teams.
- **Recognition**: Named a top employer by Built In and industry awards.
- **Caution**: KAYAK warns of fraudulent job ads – all genuine recruitment ends with @kayak.com, and no payment is ever requested from candidates.

## Sources
1. [kayak.com](https://www.kayak.com/careers/)
2. [kayak.com](https://www.kayak.com/about)
3. [kayak.com](https://www.kayak.com/c/help/about/)
4. [builtin.com](https://builtin.com/company/kayak)
5. [linkedin.com](https://www.linkedin.com/company/kayak)

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