Senior Data Scientist in London

We power people’s progress. At Preply, we’re all about creating life-changing learning experiences. We help people discover the magic of the perfect tutor, craft a personalised learning journey, and stay motivated to keep growing. Our approach is human-led, tech-enabled - and it’s creating real impact. We’ve just reached unicorn status with a $150M Series D, accelerating our vision to transform education through human-led, AI-enhanced learning. Today, 100,000+ tutors teach 90+ languages to learners in 180 countries - and we’re only getting started. As a category-defining company, we’re shaping what the future of learning looks like at global scale.

Every Preply lesson sparks change, fuels ambition, and drives progress that matters. Joining Preply means helping define the future of education at global scale, and building something that truly matters for millions of people, every day.

Meet the team: At Preply, we're growing a talented Data Team to empower top-notch decision-making across our organization. Our team collaborates closely with various other chapters - including product, business, and platform - leveraging analysis, experimentation, causal inference, and machine learning. You’ll be embedded in cross-functional teams, partnering with our MarTech Product Manager, Marketeers, Tech Leads, and the Data Strategy team.

What you’ll be doing:

• Collaborate with performance marketing teams in coming up with data solutions to support the optimization of marketing campaigns, budgets and results;
• Roll out Marketing Mix Modeling (MMM) to more countries and help build an automated MMM budget platform using advanced Bayesian statistics;
• Design and analyze incrementality tests to measure marketing effectiveness, applying advanced methods like causal inference to quantify incremental ROI;
• Design a unified system that connects the dots between MMM and incrementality results;
• Shape the testing roadmap;
• Design our Creative Analytics framework, developing new metrics such as creative fatigue to help scale new channels;
• Improve targeting and bidding strategies by using regression models to assign predictive weights to funnel events;
• Act as a sparring partner to our Applied AI team: support the roll-out of models, analyze their impact, understand feature importance, and bring both business and data science knowledge to guide these projects;
• Work closely with the Data Engineering team in the creation of scalable data pipelines while guaranteeing an optimal evolution of our ETL processes, as well as the adoption of new tools and frameworks;
• Contribute to cross-company initiatives in alignment with our data organization's vision;
• Support proactively the application of predictive models in performance marketing channels.

What you need to succeed:

• An AI mindset: you use AI to boost your efficiency, love working agentically, automate processes, and enable your stakeholders with AI;
• A pragmatic problem-solver at heart: you dig into complexity to find the simplest, most elegant path through it, guided by curiosity rather than a love of complicated models;
• Extensive experience as a Data Scientist working with performance marketing teams in a B2C environment, delivering business insights and building data products;
• Knowledge of incrementality and attribution;
• Skilled in developing and deploying machine learning models;
• Experience with experimentation (design and evaluation of A/B tests);
• Experience working in Marketplaces and/or digital business environments, in the context of performance marketing;
• Strong coding skills in SQL and Python;
• Creative mindset and proactive attitude towards the creation and evaluation of new solutions;
• Strong curiosity, problem solving and problem finding skills;
• Advanced written and verbal communication skills in English.

Nice to have:

• Previous experience with causal inference techniques (e.g. geo-lift testing, causal impact, synthetic control, difference in differences, etc.)
• Previous experience with Databricks, Snowflake, Looker;
• Previous experience with Apache Spark;
• Knowledge of data orchestration tools (e.g. dbt and Airflow).

Why you’ll love it at Preply:

• An open, collaborative, dynamic and diverse culture;
• A generous monthly allowance for lessons on Preply.com, Learning & Development budget and time off for your self-development;
• A competitive financial package with equity, leave allowance and health insurance;
• Not in Barcelona? We offer an attractive relocation package to join us in our Preply Barcelona Hub;
• Access to free mental health support platforms;
• Access to Gympass-partnered wellness and gym centers throughout Spain to promote and support well-being and physical health;
• The opportunity to unlock the potential of learners and tutors through language learning and teaching in 175 countries (and counting!).

Our Principles:

• Care to change the world - We are passionate about our work and care deeply about its impact to be life changing.
• We do it for learners - For both Preply and tutors, learners are why we do what we do. Every day we focus on empowering tutors to deliver an exceptional learning experience.
• Keep perfecting - To create an outstanding customer experience, we focus on simplicity, smoothness, and enjoyment, continually perfecting it as every detail matters.
• Now is the time - In a fast-paced world, it matters how quickly we act. Now is the time to make great things happen.
• Disciplined execution - What makes us disciplined is the excellence in our execution. We set clear goals, focus on what matters, and utilize our resources efficiently.
• Dive deep - We leverage business acumen and curiosity to investigate disparities between numbers and stories, unlocking meaningful insights to guide our decisions.
• Growth mindset - We proactively seek growth opportunities and believe today's best performance becomes tomorrow's starting point. We humbly embrace feedback and learn from setbacks.
• Raise the bar - We raise our performance standards continuously, alongside each new hire and promotion. We build diverse and high-performing teams that can make a real difference.
• Challenge, disagree and commit - We value open and candid communication, even when we don’t fully agree. We speak our minds, challenge when necessary, and fully commit to decisions once made.
• One Preply - We prioritize collaboration, inclusion, and the success of our team over personal ambitions. Together, we support and celebrate each other's progress.

Diversity, Equity, and Inclusion: Preply.com is committed to creating an inclusive environment where people of diverse backgrounds can thrive. We believe that the presence of different opinions and viewpoints is a key ingredient for our success as a multicultural Ed-Tech company. That means that Preply will consider all applications for employment without regard to race, color, religion, gender identity or expression, sexual orientation, national origin, disability, age or veteran status.