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Site Reliability Engineering at Booking.com

What We Do

With millions of transactions per day, Booking.com requires a solid infrastructure that’s constantly monitored.

Our Site Reliability Engineers improve upon the performance and dependability of our varied technology systems, continuously working towards bringing big ideas to reality.

They build and embrace change, coding their way to ensure the scalability and efficiency of our vast infrastructure – and then make sure it all works together, so that this e-commerce engine runs smoothly.

28 million listings in
150,000 destinations

Carbon neutral
offices since 2020

150 nationalities represented

140 offices in
70 countries

From running marathons to building software that helps millions of customers around the world experience the world.

Meet Alibek, our Engineering Manager and discover what he most enjoys about his work at Booking.com

What can I expect as an SRE at Booking.com? 

  • Work with some of the best SRE communities around, contributing a high scale, complex, world-renowned product and see the real-time impact of your work
  • Freedom to use innovative tools and methods to refine the systems used by product teams to improve the experience of millions of Booking.com customers
  • Excellent progression across engineering with opportunities to move to Senior/Principal/Team Lead, fast
  • Thrive with excellent benefits, development opportunities and community-focused events and conferences
  • Succeed in the new normal with our flexible, hybrid way of working & work abroad program

Our People's Perspective

Interviewing for Site Reliability Engineer positions

Interviewing for an SRE position at Booking.com is a three-part process: a coding interview; a systems design interview; and finally, a behavioural interview, designed to help you express the success attributes you bring to the role, understand how you think and collaborate, and to assess your commercial acumen and motivation for the role.

Our recruitment process can take anywhere from 3-6 weeks, but of course this depends on the complexity of interviews that are required for each role. 

Your Recruiter will be with you every step of the way with resources, feedback and tips to help you to prep for success. 

The first stage after application is a phone call with our Sourcers or Recruiters – this will cover an overview of your career history, your knowledge, skills and experience as well as your interest in the role you’ve applied to. While there is not anything specific you can prepare, it is a great idea to have your CV to hand as well as a copy of the job posting you applied to. You can even have some examples of the knowledge, skills and experience you have gained in your career so far.

During this round (60 mins), we will present you with one problem statement for which you will have to solve by finding the correct Data Structure and Algorithm. You will be able to choose your preferred programming language to complete this.

  • Make sure you fully understand all the data available to you and ask clarifying questions before jumping into coding. 

  • Think out loud. We want to know how you solve problems. This can be just as important as the right answer. If you think out loud, you give us insight into your thinking process. Moreover,  your interviewer can then support you with more information and  hints when you need them. 

  • Be prepared to code on paper. So, no syntax highlighting, coding templates, and tool sets. Manage your time effectively. Get a thorough understanding of the core problem and problem space. Discuss any trade-off to your solution and don’t aim for perfection. Start simple, give details about what needs attention and improvement. Then, iterate on the solution.

  • Share your reasoning. Engineering is all about trade-offs, so be prepared to discuss these trade-offs to your solution or identify any edge/corner cases in the problem.

  • Find and fix the bugs by yourself. Don’t wait for the interviewers.

  • Use the hints that you get. The interviewers know the question well enough to give the right hint if you get stuck.

During this interview (75 mins), we will ask you to solve a problem by showing your ability to design, explain and justify a robust and scalable system, as well as troubleshooting any issues around it.

  • Before you start your design, make sure to ask clarifying questions to understand the full scope of the requirement and all the details available in the input. 

  • Just like the previous round, we recommend you are vocal about your reasoning and think out loud, as well as to actively listen for any potential hints or tips coming from the interviewers.

  • Whether it’s top-down or bottom-up, we recommend a layered approach to Systems Design, where you go through each layer and look at each layer, each component and how they interact with each other.

  • Look for any unnecessary elements in the design or anything that could lead to a SPOF or an incomplete solution.

  • Be prepared to discuss any trade-offs to your solution and provide low-level details or justifications for each technical decision you make. 

  • Focus on Observability. We want you to bring a metrics-driven approach, where you can show us your understanding of system and service-level metrics, especially SLOs, SLIs, etc. and how you can incorporate them into your design.

This is the final step in the interview process, where you will be meeting your next potential Manager at Booking.com or another Manager from the same team. This is a great opportunity for you to ask questions about your next potential team.

  • We want to evaluate your mutual fit with Booking.com, your communication, values, collaborative approach and your motivation for the role.

  • Commercial Awareness. Do you know how your business generates revenue and how your work impacts it?  Be prepared to discuss projects from your experience where you have made an impact.

  • Be prepared to answer behavioural or situational questions about your experience: “Tell me about a time when…” or “How would you…?”. We recommend the ‘STAR’ interview technique to provide structured and concise answers. We want to see how you can learn from your mistakes, from other colleagues and how you always aspire to learn forever. 

  • Think Customer First and how your work has an impact on the end user.

  • Bring a data-driven approach whenever possible, not just mentioning “data”, but providing actual insights that can further explain your answer.

Our assessment process is we want to get to know you better in the following fields:

Coding skills & Problem-solving with code

  • Coding skills & Problem-solving with code. An ideal candidate will have solid experience in at least one programming language, including software design and architecture skills. We look for people who can solve operational issues using a software engineering approach. Our SREs also rely on data structures and algorithms from time-to-time to solve complex programming challenges.

  • Systems Design & Architecture. At Booking.com we own and build complex and distributed systems at scale. Experience in building, operating and maintaining scalable distributed systems, with a focus on operations automation is a distinct advantage. DevOps Engineering and Infrastructure Automation/Orchestratialso on play a big part in the role of an SRE. A strong candidate will be able to propose a design from scratch and justify each component involved in the different layers of your system and how each of these can interact with each other.  

  • Observability. For us, observability is much more than just basic alerts and dashboards. Our SREs have a deep understanding of different system and service-level metrics like SLOs and SLIs and how to monitor them to understand the performance of a system, while proactively debugging or troubleshooting any issues around it. 

We tend to work in smaller, agile teams. Most of our teams have 6-12 members, but may vary based on a department. For example, in our development teams, you will also collaborate with other functional teams including Product Owners, Designers and Testers.

The majority of our interviews are conducted via video conferencing. 

As we move into a more hybrid way of working, with our employees dividing their time between home and the workplace, we believe that our offices will continue to serve as an important place for colleagues to come together, innovate and collaborate face-to-face on a regular basis. We know from research with our employees that they still value and need time together in the office to connect and collaborate. As such, our aim is to create a flexible concept that we can continue to adapt to meet the evolving needs of our workforce.

“Our engineering culture at Booking.com is embodied by our core values: Own It and Learn Forever. Teams and engineers are empowered with ownership of their product and solution – and we are continuously improving our skills, tech estate, and products. We learn from each other, from our customers, from our successes, and from our mistakes.” – Austin Sheppard, VP Engineering, Trips

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