Senior Backend Engineer, Vinted Pay

As a Senior Backend Engineer, you will be responsible for building and running the verification systems behind Vinted Pay: identity verification (document and biometric checks), electronic KYC (identity and address matching against external data sources) and bank account verification (Confirmation of Payee and Verification of Payee). These checks answer one question for millions of members: "is this person who they say they are, and is this really their bank account?" Every onboarding, balance activation and payout in Vinted Pay passes through them.

You will join Verifications, a team in the Vinted Pay domain made up of 3-4 backend engineers, an engineering manager (your reporting line), a product manager and a decision scientist. The team is young and the service is still taking shape: verification logic is being extracted from older Ruby services into a single Go service that is becoming the source of truth for every verification a member has ever done, and we are making verification resilient to provider outages instead of dependent on any one vendor. This is architectural work with direct product and compliance impact, not just feature delivery.

Problems arrive ambiguous. Engineers here aren't handed specs - they work out what's actually needed together with product and compliance, align it across teams, and build it.

• Work in a compact team where nobody owns just one corner: engineers deliberately move between identity verification, eKYC and bank verification, so over time you'll know the whole domain, not a slice of it.
• Build and own third-party integrations end-to-end: the client, the callbacks, the durable Temporal workflow that drives a verification to a final decision even when the provider never calls back, the dashboards and SLA alerts, and the shared channel with the vendor when something is wrong on their side.
• Design for provider failure: build the provider router that spreads traffic across providers by weight, tracks provider health, remembers what failed for a member and reroutes their retry, so that one provider outage no longer means a member can't verify.
• Run A/B tests between providers to decide where traffic should go, and roll verification rules out to new markets.
• Own topics end-to-end: from an ambiguous requirement to a written technical plan in the repository, through cross-team alignment, implementation, rollout behind feature flags, and monitoring in production.
• Handle personal data with care: PII tagging, log masking, and GDPR retention and deletion across our database, object storage and external providers are part of everyday work, not an afterthought.
• Work in an AI-assisted way: agentic coding tools (Claude Code, Cursor, Codex and others) are part of the daily workflow here, for building, debugging, investigating production issues, and writing plans and docs. We expect you to use them well and make the team better at it.
• See your code affect millions of users almost instantly. Our main branch gets rolled out straight to production on each merge. We deploy many times per day.
• Work with a modern Go stack: Go, Temporal, Kafka, MySQL, Redis, S3, OpenAPI-first code generation, testcontainers, Prometheus, Grafana, Kubernetes on AWS. We don't expect you to be familiar with all of them beforehand, but we expect you will be excited to learn them fast.
• Write unit tests for all of the code you write and contribute to integration and E2E test writing and its usage.
• Take ownership of critical alerts and business metrics for your team to ensure our services achieve 99.99% availability.
• Participate in on-call rotations and a weekly rotating point-of-contact duty in our public Slack channel, where AML, member support, compliance and other Vinted Pay teams bring their verification questions.

• Have solid experience building and running backend services in production, in Go or a language close enough that you can become productive in Go quickly.
• Have hands-on experience integrating third-party APIs and dealing with what goes wrong with them: timeouts, rate limits, inconsistent responses, callbacks that never arrive.
• Have a strong understanding of distributed systems fundamentals: idempotency, at-least-once delivery, workflow orchestration, keeping data consistent across services.
• Care deeply about observability: your services have dashboards and alerts before they have traffic, and you're comfortable being the one paged when they fire.
• Demonstrated ability to take an ambiguous problem, write a clear proposal, and align several teams around it.
• Comfortable handling personal data responsibly and working within compliance and regulatory constraints.
• Good at explaining technical trade-offs to non-engineers, and at giving code and design reviews that make others better.
• Excellent written and spoken English.

Nice to have

• Advantage: Experience in payments, fintech, KYC/AML or another regulated domain.
• Advantage: Experience with Temporal or a similar workflow engine.

• The opportunity to benefit from our share options programme
• 25 working days of holiday
• Access to all the tools & tech needed for work
• Home office support: we provide IT workstation equipment and a personal budget of up to 540 for home workplace furniture
• Private health insurance
• Pension plan with flexible contribution options and a matching contribution from Vinted
• Confidential Employee Assistance Program (EAP) for you and your family
• Frequent team-building events
• A personal monthly budget for shopping on Vinted
• A dog-friendly office
• In Vilnius office: Gym & in-house meals at friendly prices
• In Kaunas office: a monthly lunch allowance, and a once-a-week provided in-house lunch and breakfast