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cozycozy Logo cozycozy · IT - Software Development

Senior Backend Engineer

France, Paris · Job Posted December 07, 2025
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Job Description

Cozycozy is the only platform that gives you real-time access to all available holiday accommodations. Whether you're searching for a hotel, apartment, hostel, villa, or even a treehouse, our service features over 20 million listings from over 100 booking sites. You will find popular options like Airbnb, Booking.com, Abritel/VRBO and hotels.com, as well as plenty of specialised marketplaces to explore, such as Agriturismo, Gîtes de France, Onefinestay, Belvilla, Sonder, Travelski, and many others.Experiencing rapid growth, we are now present in over 50 countries in 20 languages, with offices in Paris and Budapest.

Job Responsibility

  • Evolve our core APIs to deliver millions of fresh results, fast by helping users find the right stay in a few clicks
  • Design and build scalable services that manage high-volume data streams from dozens of partners
  • Collaborate on architecture decisions to prepare our platform for rapid growth
  • Work closely with product & data to ship new features that directly impact travelers’ choices
  • Continuously improve performance & reliability because in travel search, speed is everything

Requirements

  • Strong experience with Node.js + TypeScript/JavaScript and RxJS
  • Deep knowledge of MongoDB, PostgreSQL, and caching systems (Redis, Dragonfly)
  • Experience designing and maintaining REST/gRPC APIs (GraphQL is a plus)
  • Hands-on exposure to Kubernetes, Docker, and modern CI/CD practices
  • Comfort working with queue systems (Google Pub/Sub, SQS) and event-driven architectures
  • Motivation to be in an international (English speaking) work environment
  • Experience handling streams of live data in a marketplace-like ecosystem
  • A product mindset. You care about user experience and data freshness as much as technical elegance

Nice to have

If you’ve worked with GoLang or Python, real-time analytics, or large-scale search platforms.

What we offer

  • Competitive salary, stock options, Alan health insurance, and Swile card
  • Enjoy our office in Paris with unlimited coffee, tea, snacks, and drinks
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