Senior II Back-End Engineer bei Preply

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 personalized learning journey, and stay motivated to keep growing. Our approach is human-led, tech-enabled - and it’s creating real impact. So far, 90,000 tutors have delivered over 20 million lessons to learners in more than 175 countries. Every Preply lesson sparks change, fuels ambition, and drives progress that matters.

Meet the team!

The MarTech team builds the infrastructure that powers Preply’s growth engine. We focus on scaling performance marketing through smart automation, precise tracking, and efficient campaign tooling.

Our work is about engineering systems that drive measurable results, from optimizing SEM and paid marketing workflows to managing SEO infrastructure, attribution, and multi-channel communications. We prioritize efficiency, data integrity, and automation to help marketing teams operate at scale and make better decisions.

You’ll work at the intersection of marketing, data, and engineering, and see the direct business impact of the systems you own.

As a Senior II Backend Engineer, you’ll set the technical direction, lead cross-functional projects, and build systems that power Preply’s global growth engine. Your work will shape how millions of learners connect with tutors worldwide, tackling challenges that are complex in scope and critical to our success.

We are tech-agnostic, meaning we are open to considering candidates with diverse technology backgrounds, such as Java/Spring, Node.js/Express.js, Ruby/Ruby on Rails, Scala/Play, PHP, or Golang.

While Python is our primary programming language, prior experience with it is not mandatory. What truly matters is your enthusiasm for learning Python and your ability to adapt quickly to using it for product development.

What you’ll be doing:

• Own and drive technical vision across two Martech squads focused on ad delivery, SEO systems, automation, and attribution.
• Develop and own backend features using Python/Django, supporting the creation of new backend services as well as design, create, and/or troubleshoot integrations with third-party vendors.
• Scope and lead cross-functional initiatives involving marketing, data, product, and other engineering teams.
• Design and implement scalable backend systems, data pipelines, and integrations with third-party platforms (e.g., Meta, TikTok, Google Ads)
• Mentor and coach junior and middle engineers across squads
• Improve performance, tracking, monitoring, and reliability of our systems with an eye on long-term scalability.
• Collaborate closely with PMs, EMs, designers, and analysts to make data-informed, user-centered decisions.
• Champion engineering best practices: test automation, documentation, observability, and quality-first culture.

What you need to succeed

• Exposure to architectural patterns of a large, high-scale web application (e.g., well-designed APIs, high-volume data pipelines, efficient algorithms);
• Proven experience leading complex, ambiguous, or greenfield projects end-to-end
• Strong communication and cross-functional collaboration skills (English level B2+)
• Willingness to be on-call for your squad (1 week every 5 weeks).

Nice to have

• Side projects or product ownership experience, especially in marketing or growth contexts.
• Experience designing systems for marketing attribution, experimentation platforms, or recommendation engines.
• Familiarity with cloud platforms (AWS/GCP) and modern DevOps practices.
• Familiarity and willing to support small JS/TS tasks when needed.

Why engineers choose Preply

Impact that scales
What you build helps unlock progress for learners in 175+ countries. Every feature you ship supports real people, reaching real goals.

Ownership that matters
We don’t just follow roadmaps, we shape them. Engineers lead bold projects, make key tech decisions, and see their work drive business results.

Learning built in
We work cross-functionally with data, product, design, marketing. So there’s always a new challenge and a new skill to pick up.

Modern tech, real standards
From cloud-first infra to observability-first ops, we prioritize scalable systems and smart engineering practices that last.

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 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 is committed to creating a diverse and inclusive environment where people from all backgrounds can thrive. Different opinions and viewpoints are key ingredients in our success as a multicultural Ed-Tech company. 

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. Together, we are The World Class.

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