Senior Software Engineer – Payments
OrderYOYO · Manchester, United Kingdom · remote
OORDERYOYO
Senior Software Engineer – Payments
Berlin €100,000. Reports to: Engineering Manager – Payments
About the Role
Join OrderYOYO's Payments team to build the backend services that process restaurant payments across multiple acquirers and payment service providers, and automate how we bill and invoice merchants for subscriptions, usage and transaction fees.
You'll own complex changes from technical design through release and production operation, working closely with Product, Finance and fellow engineers. Your work will improve the accuracy and reliability of charges, payouts, invoices and reconciliation, while reducing routine manual Finance work.
Our backend services are built in .NET and run in a Microsoft Azure cloud environment. We value transferable experience: you don't need to have used every one of these technologies, provided you can demonstrate strong backend engineering judgement.
Role Mission
Build and evolve OrderYOYO's payments, billing and invoicing capabilities, ensuring accurate financial processing, reliable payment integrations and automated merchant billing. You'll help strengthen the resilience, security and maintainability of our financial systems while reducing manual intervention and supporting our growing international restaurant platform.
Core ResponsibilitiesPayments and Billing Services
- Design, build and maintain backend payments and billing services covering payment processing, payouts, subscriptions, recurring charges, usage and transaction-based fees.
- Implement pricing, discounts, fees, tax and collection rules in collaboration with Product and Finance, involving Security and other specialists where required.
- Support merchant-specific pricing and billing requirements through maintainable configuration and reusable capabilities, including multi-currency, VAT and local tax requirements across our markets.
Acquirer and PSP Integrations
- Build and maintain integrations with card acquirers and payment service providers for online and in-store payments, covering authorisation, capture, settlement and payouts.
- Help develop a multi-acquirer, multi-PSP payments architecture with routing and failover to reduce dependency on individual providers.
- Ingest and reconcile acquirer settlement reports against transactions, fees and merchant payouts.
- Work with acquirer and PSP partners through onboarding, certification and changes, including card scheme and compliance requirements.
Invoice Automation
- Automate invoice generation, corrections and collection workflows, including credit notes, dunning, direct debit collection and cash application, with appropriate approvals, audit trails and exception handling.
- Support e-invoicing and local invoicing requirements, integrating invoice data with Finance and accounting systems.
Platform Integration and Financial Correctness
- Integrate payments, billing and invoicing with our POS and ordering systems and third-party billing or accounting tools.
- Design financial workflows that safely handle duplicate and out-of-order events, retries, partial failures and precise monetary calculations, with clear audit trails.
- Handle refunds, chargebacks and failed payments correctly across payments, billing and invoicing.
- Build and improve reconciliation between transactions, fees, payouts, invoices and finance records, making unmatched items visible and straightforward to resolve.
- Follow security and compliance standards for financial and payment data, including PCI DSS and GDPR where relevant.
Quality and Operations
- Build automated tests for financial calculations, provider integrations and failure scenarios, including retries, partial refunds, pricing changes and reconciliation discrepancies.
- Validate pricing changes, migrations and backfills, delivering them through controlled and safe releases.
- Set up actionable monitoring and alerting for payment processing, billing runs and invoice delivery, investigating issues through to root cause.
Senior Technical Leadership
- Lead technical design for complex changes, explain trade-offs and break delivery into manageable, safe increments.
- Own the reliability and maintainability of the services you work on, improving existing code, data models and integrations.
- Support the development of other engineers through design reviews, constructive code reviews, mentoring and knowledge sharing.
- Explain payments and billing logic clearly to non-technical stakeholders and document decisions so knowledge is shared across the team.
Outcomes You Will Help Deliver- Accurate billing runs and invoices completed on schedule.
- Reduced routine manual intervention, with clear handling of exceptions.
- Reliable payment and reconciliation services, supported by actionable monitoring.
- Resilient payment processing across multiple acquirers and PSPs, with settlements reconciled reliably.
- Safe delivery of agreed capabilities and fewer recurring production defects.
Targets will be agreed against current baselines for the services you own. Wider measures, such as payment success rate, revenue leakage and collection performance, will be shared with the Payments, Finance and commercial teams.
Must-Have Requirements- Strong backend engineering experience, including responsibility for production services.
- Proven experience building billing and invoicing systems, including automating invoicing or collection workflows.
- Hands-on experience integrating with card acquirers or payment service providers, including authorisation, capture, settlement and payout flows.
- Strong SQL, relational data modelling and data integrity skills, with experience handling financial data where precision matters.
- Experience with REST APIs, webhooks and asynchronous integrations, including safely handling failures, retries and idempotency.
- Experience with automated testing, CI/CD, monitoring and incident investigation.
- Ability to lead technical design and translate Finance and Product requirements into software.
Strong-to-Have Experience- Experience with acquirer settlement and reconciliation, card scheme rules, multi-provider routing or in-store and terminal payments.
- Commercial experience with .NET and Azure.
- Experience with the providers and platforms we use, or similar platforms such as Stripe, Adyen or Chargebee.
- Experience with e-invoicing, multi-currency, VAT and accounting integrations across European markets.
- A background in FoodTech, restaurant platforms, B2B SaaS or fintech.
- Experience modernising financial systems.
Who We AreAt OrderYOYO, company culture comes first. We create a positive, inclusive environment where people are trusted to do their best work and take ownership of what they build. We look for engineers who take ownership, raise risks early, explain decisions clearly, collaborate respectfully and follow through on commitments.
Our values describe what that looks like day to day:
- Passion: Adaptable and positive in a fast-moving environment, proactive about improving how things work.
- Action: Leads by examamples
- Compassion: Supports colleagues and considers the impact of decisions on merchants and teammates.
- One Team: Communicates clearly in writing and in person, stays calm under pressure and shares information openly.
We help restaurants succeed online by providing branded websites, mobile apps and tailored marketing solutions, giving them full control of their business. By removing high commission fees charged by third-party platforms, we empower restaurants to grow sustainably.
Through our partnership with AppSmart, the market leader in POS and in-store systems, we've become the largest restaurant-focused platform in Europe.
What We Offer- A salary of €100,000 per year.
- A role based in Berlin.
- High ownership and autonomy over the services you build.
- The opportunity to work on revenue-critical production systems.
- A strong focus on security, reliabili