Senior Backend Engineer - Walking Motivations Pillar (FR)

Hi there!

About us

WeWard is the app that rewards you for walking and turns everyday steps into real-life rewards, connections, \& positive impact!

Our mission is to help people move more, feel better, and make movement meaningful.

Today, we are trusted by 25M users worldwide , with a fast-growing, international team and offices in Paris and New York.

Our ambition is to build the world’s leading movement-and-rewards platform, scaling globally while using technology, data, and smart incentives to drive lasting behavior change and wellbeing at scale.

** ** About the role

Reporting to the Walking Motivations team , alongside Surya , you’ll work as a Backend Engineer on the pillar that puts the walk back at the heart of WeWard.

WeWard rewards walking — but rewards aren’t the whole story. Our Walking Motivations Pillar exists to make walking itself feel good: more habitual, more meaningful, more fun. We build the features people open the app for before they ever think about the reward.

You’ll face the challenge of operating a large-scale international consumer app handling billions of interactions and strong peaks of activity every day.

The Walking Motivations Pillar works on 3 core ambitions:

• Step uplift — a measurable increase in daily steps. We move the body, not just the metric.

• Lasting motivation — making walking a habit users come back to on their own.

• A wonderful experience — the kind of product moment that turns a user into a multi-year member.

Your impact/responsibilities

As a Senior Backend Engineer inside the Walking Motivations Pillar, you will:

Ship and own

• Ship reliable APIs, services and data pipelines end-to-end

• Power our walking experiences — step ingestion at scale, real-time gamification loops (challenges, streaks, rewards, progression), habit feedback, social mechanics

• Build the event-driven backbone that turns every step into a signal the product can react to instantly

• Design the data foundations that let us understand how people walk, not just how much

Drive technical excellence

• Optimise critical paths — at our scale, milliseconds and percentages matter

• Contribute to pillar-level architecture with the CTO and Engineering Manager

• Spot fragile areas, debt, and security risks before they become incidents

• Reduce long-term debt without derailing the roadmap

Collaborate and mentor

• Frame trade-offs with PMs and Mobile engineers

• Guide pillar engineers on complex technical decisions

Our stack is mainly Python (Flask, FastAPI) with event-driven architectures (Kafka, async processing) where it matters. We value scalable architecture more than the language you use, and you should be comfortable working on infrastructure at scale, where optimization and performance are the key to handle our millions of users.

Our commitments

• ** SUCCEED** — You’ll join a team of passionate people who share values of ambition and determination

• ** TRUST** — We give you real autonomy, trusting you to reach your goals in your own way

• ** ️ EXPLORE** — You’ll grow in a culture that’s constantly evolving and curious about what’s next

• ** PROGRESS** — We’ll support you through challenges, learn from mistakes, and move forward together

• SMILE — And every day, you’ll be part of a fun and positive environment where humor is always welcome

Preferred experience

** What we’re looking for**

You’re the perfect match if…

• You have 6 years of experience as a Backend Engineer (mostly python) , with hands-on exposure to large-scale, high-traffic systems and a strong sense of ownership over what you build

• You love combining continuous improvement and agility , always bringing new ideas to the table. At WeWard, our spirit is Test \& Learn — we trust you to experiment (we deploy to production more than ten times a week!)

• You have a natural interest in the startup world and want to make a tangible impact in your next adventure

• You’re motivated by contributing to the health and wellness sector — and you genuinely care about whether someone walks more because of what you built

• You’re eager to evolve in an international environment — WeWard is now present in Spain, Italy, the US, Germany, the UK, and more!

If this sounds like you, apply — we’d love to meet you.

What we offer

• ️ A global, mission-driven team with teammates in Paris, NY, London, Boston!

• ️ A healthy work/life balance (we walk the talk)

• Annual learning \& dev budget (you grow, we grow)

• Hybrid work, with 2 days of remote work per week

• (Really, really) Cool office in central Paris with snacks, a walking desk and a huge Wardy hanging around

Recruitment Timeline

1. 30-min call with Valentine our Talent Acquisition Lead — to discuss your background, expectations, and answer your last questions about WeWard!

2. 1-hour technical chat with your future manager — to dive into the role and missions.

3. At-home case study followed by a 1 hour debrief with 3 collaborators, including time for mutual feedback.

4. Office tour to meet other team members.

And if it’s a match… Welcome to the adventure!

Apache, React.js, Python

WeWard is the app that rewards you for walking and turns everyday steps into real-life rewards, connections, \& positive impact!

Our mission is to help people move more, feel better, and make movement meaningful.

Today, we are trusted by 25M users worldwide , with a fast-growing, international team and offices in Paris and New York.

Our ambition is to build the world’s leading movement-and-rewards platform, scaling globally while using technology, data, and smart incentives to drive lasting behavior change and wellbeing at scale.