Senior Backend Engineer

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

Our Monetization team is growing, and we’re looking for a Senior Backend Engineer to join the journey and help us make WeWard the default gateway for online shopping — with tracking and rewards our users can trust.

You will report to Ivan and work closely with Product, Data, Customer Success, and our affiliate networks and partners.

Your impact/responsibilities

As a Senior Backend Engineer in the Affiliation squad at WeWard, you will:

• Own the backend of our affiliation platform — partner catalogue, offer and reward configuration, click-out, tracking, purchase attribution and reward crediting

• Integrate and maintain our affiliate networks and providers — feeds, APIs, S2S postbacks and callbacks — and turn each new partner integration into a faster, more standardised & agentic process

• Make tracking trustworthy end to end, cutting untracked and mis‑attributed purchases, our single biggest driver of support tickets and negative store reviews

• Rebuild the claims flow so users get a shorter time‑to‑reward, clear reasons when a purchase is rejected

• Get reward computation right across promo and flash offers, level‑up bonuses, caps and category rules — where a rounding error is real money in both directions

• Scale the system across markets with per‑country partners, currencies and reward rules

• Instrument and monitor the pipeline so a broken partner feed is caught by an alert, not by a Zendesk ticket

• Work hand in hand with Product, Data and Customer Success to prioritise against revenue, conversion and satisfaction KPIs

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 7+ years of backend experience, with strong Python, ideally in a consumer product at scale

• You have proven experience in the affiliation or cashback industry — you’ve worked with affiliate networks, publishers, or a cashback product, and you know how tracking, attribution windows and partner validation actually behave in production

• You’re comfortable with PostgreSQL on large volumes and with asynchronous processing (queues, workers, scheduled jobs)

• You’ve built and maintained integrations with third‑party APIs you don’t control — webhooks, postbacks, feed ingestion — and you think in terms of idempotency, retries, and reconciliation

• You have a data‑integrity mindset: when a system credits users with real value, you know the difference between “the job ran” and “the numbers are right”

• You take ownership in production — monitoring, alerting, and debugging a partner integration that silently stopped sending conversions

• You’re pragmatic and autonomous, able to arbitrate between a quick fix that unblocks revenue and the rework that prevents the next incident

• You communicate clearly in English and enjoy working closely with non‑technical stakeholders

• Bonus: experience in adtech, payments, or e‑commerce tracking, or anywhere attribution and money movement meet

• You have a startup soul, hungry to make an indelible mark on a dynamic team

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)