Senior Backend Engineer, Personalization

<h3>Company Description</h3><p>Wolt is a technology company that makes it incredibly easy to discover and get the best restaurants, grocery stores and other local shops delivered to your home or office. Wolt is not just a delivery app – we’re a technology company building a commerce platform to seamlessly connect our millions of customers with thousands of merchant and courier partners, in real-time across 23 countries and 250+ cities. Our apps (iOS and Android) have the industry’s highest ratings, largely thanks to our customer-first-mindset, which shows in how we build products and run operations. In June 2022 we officially joined forces with DoorDash. Combined, we have a presence in 27 countries, 23 of which operate with the Wolt brand and app. Wolt and DoorDash continue largely independently, with Wolt’s name, brand, product, technology and team.</p><p><strong>Working in Product Development at Wolt</strong></p><p>At Wolt, we’re about getting things done. You’ll probably enjoy it here if you like taking ownership, developing yourself and being around friendly, humble and ambitious people. </p><p>The behind the scenes of Wolt is run by an awesome bunch of over 400+ planners, builders, designers and data crunchers. We call ourselves Product+, as we’re the very core of Wolt’s products, tools and platforms. To build our products, we work in over 40  cross-functional, independent and autonomous teams. Teams are made up of a mix of talented individuals: engineers, designers, data scientists, analysts, and product leads. Each team takes ownership for solving customer problems in the best possible way.</p><p><strong>Our Commitment to Diversity, Equity &amp; Inclusion</strong></p><p>We want to have all sorts of people in our team – people like you and me, and people different from you and me. To be able to work with diverse teammates – when it comes to gender, age, ethnicity, life background, sexual orientation, political views, religion, or any other personal trait – we consciously aim to offer equal opportunity for everyone to work with us. This is because we believe diverse teams make the most thought-through decisions and build things in the most inclusive way.</p><p>Join us today to build Wolt together!</p><h3>Job Description</h3><p>Wolt is looking for a Senior Backend Engineer to join our Personalisation Team, who is responsible for creating a personalized experience on the consumer-facing components of Wolt.<br/><br/>The Personalization Team plays a unique role within the engineering teams at Wolt as we directly influence what and how content is shown to Wolt users on the client apps! Backend Engineers, Data Scientists and Machine Learning Engineers work hand in hand to develop and deploy machine learning models, design and run experiments, monitor performance and continuously improve the ranking quality. This ensures our customers find the content they look for in all markets we operate. Our machine-learning models are mostly built from scratch and are highly customised for our use case! </p><p>Hence, as part of the responsibilities, you’ll be working with our team’s Data Scientists and Machine Learning Engineers to extend and continuously improve our backend services, help the team to integrate new Machine Learning-based solutions into our infrastructure and Python backend, as well as build customer-facing A/B tests, all while maintaining and continuously improving the scalability and robustness of our systems. For example, one of our recent projects is a re-implementation of our core ranking algorithm to improve the customer experience; this includes scaling the model to multiple markets, deploying it to a modern machine learning infrastructure, and AB-Testing it within the client apps.</p><p>We have a strong Python community at Wolt (check out our <a href="https://www.youtube.com/channel/UCXmJHnCmiyKNyB4dFBFdAiA/playlists">Wolt Tech Talks Youtube channel</a> and our <a href="https://blog.wolt.com/tag/engineering/">engineering blog</a>) - modern Python (FastAPI, gRPC, usage of type hints) is our bread and butter. But we are not limited to Python; Wolt has a fantastic sharing and learning culture, and everyone is invited to learn, share best practices and choose the best technology for the job. </p><p>This role can be based in one of our tech hubs in Helsinki, Berlin or Stockholm, or you can work remotely anywhere in Finland, Sweden, Germany, Denmark, and Estonia. Read more about our remote setup <a href="https://blog.wolt.com/hq/2021/03/23/new-remote-setup-at-wolt-product-work-from-anywhere-in-finland-germany-denmark-estonia/?_gl=1*1spku7f*_ga*MTI0NDgzMTIwNi4xNjU3Njk4NDM4*_ga_CP7Z2F7NFM*MTY2ODUwNDQzOS43NS4xLjE2Njg1MDU2MzcuNDQuMC4w">here</a>. If you live outside of these countries - not to worry! We provide relocation support to help you make your way to Finland, Germany or Sweden.</p><h3>Qualifications</h3><p>The team writes mainly Python (Flask, gRPC), and we expect you to have a strong professional ba