Senior Full-Stack Engineer (back-end heavy) 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.

Our team builds scalable, resilient products using Python/Django on the backend and React on the frontend, all with one goal in mind: creating a smooth, meaningful experience for our learners and tutors. We're proudly tech-agnostic; great engineers come from all kinds of backgrounds. Whether you’ve worked with Java/Spring, Node.js, Ruby on Rails, Scala/Play, PHP, or Go, you’ll feel right at home here. Python experience isn’t required.

We make decisions based on data and real user feedback: running A/B tests, shipping iteratively, and constantly improving. We also put a strong focus on observability, monitoring, and metrics, so we can keep our systems healthy and continue optimizing at scale. At Preply, we ship 50–60 times per day, thanks to a solid CI/CD setup and a culture that values action over ceremony. As a fast-growing company, you’ll find a wide range of technical challenges, the kind of work that keeps you learning, stretching, and growing.

What you’ll be doing

• Work in a cross‑functional team alongside the Product Manager, Product Designer, UX Writers, Data Analytics, Technical Leads, Engineers and other cross‑functional team members to deliver engaging features through A/B tests and build top‑notch products.
• Back‑end Development: Develop and own backend features using Python/Django, supporting the creation of new backend services and designing, creating, and troubleshooting integrations with third‑party vendors.
• UI Development: Develop frontend features in React/Typescript, launched in our A/B experimentation framework.
• Implementation: Take on the responsibility of writing services from initial concept to full‑fledged deployment.
• Raising the bar of our end‑to‑end solutions: Leverage previous experience to implement and socialize current best practices in frontend and backend.
• Use a Data‑driven approach: Our goal is not to deliver code but to deliver user value. Data‑driven approaches and experimentation are its heartbeats.
• System Design: Design efficient system architectures that align with team goals, constraints and schedules.
• Prioritisation: Strike a balance between delivering fast results and maintaining high‑quality, sustainable systems.
• Chasing Excellence: Embody a commitment to excellence in all aspects of your work.

What you need to succeed

• Full‑Stack Expertise: This role is primarily backend‑focused, with about 70‑80% of the work on back‑end development and 20‑30% on the front‑end, requiring solid backend expertise and well‑rounded full‑stack engineering skills.
• Exposure to front‑end tech: A good understanding of React, Typescript, HTML5, and CSS.
• Exposure to architectural patterns of a large, high‑scale web application (e.g., well‑designed APIs, high‑volume data pipelines, efficient algorithms).
• Proactive Problem‑Solving: You will be expected to face and solve challenges independently, both in the codebase and in our product initiatives.
• High level of self‑organization, ownership, and responsibility.
• Communication Skills: Good at working with others and communicating effectively in English at a B2 level or higher.
• A great collaborator with excellent verbal and written communication skills.
• Willingness to be on‑call for your squad (1 week every 5 weeks).

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.
• Access to free mental health support platforms.
• The opportunity to shape the lives 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.