Senior QA Engineer New Barcelona, Spain

Cross River builds the infrastructure behind the world’s most innovative financial products. Our technology and capital solutions power payments, cards, lending, and digital asset capabilities that move money safely, instantly, and inclusively — trusted by leading fintechs, enterprises, and disruptors across the globe.

Our mission is simple: to build the financial infrastructure that expands access and opportunity for all. Guided by a culture of collaboration, curiosity, and purpose, Cross River has been named one of American Banker’s Best Places to Work in Fintech year after year. Whether you’re designing code, solving regulatory puzzles, or developing strategy, you’ll join a team where innovation and integrity drive everything we do — and where your work helps shape the future of finance.

Senior QA Engineer - Card Processing

We are seeking a Senior QA Engineer to join our Card Processing team. You will design and build the quality systems that keep our payment platform reliable at scale — in an environment where new code is produced using AI tooling and judgment is the bottleneck, not generation speed. This is not a traditional "write and execute test cases" role. We believe software engineers own their tests — your job is to make them better at it. You will own the sensor strategy that catches what AI gets wrong, verify that test intent matches business requirements, and raise the quality bar for the entire team.

Responsibilities

• Design and implement layered quality sensors across our CI/CD pipeline — from static analysis to AI‑driven code review passes
• Improve and maintain E2E test suites for critical payment flows (card authorisation, clearing and settlement, tokenisation, 3D Secure)
• Review PRs for test intent alignment — ensuring AI‑authored and human‑authored code meets the same quality bar
• Identify test coverage gaps and prioritise them by risk (customer impact, regulatory exposure)
• Build load testing and performance validation frameworks
• Collaborate with the team on quality strategy — you raise the bar, you don't gatekeep it
• Explore chaos engineering approaches to validate system resilience
• Contribute to audit‑trail thinking — ensuring generated diffs and suppressed checks are traceable and defensible

Qualifications

Required:

• 5+ years in software engineering with a strong focus on quality and testing (equivalence partitioning, boundary analysis, risk‑based prioritization)
• Proficiency in Go (or strong willingness to learn — test‑design thinking matters more than language syntax)
• Demonstrated AI fluency — you use AI assistants daily, you know when they're wrong, and you know when NOT to use them
• Experience testing RESTful APIs and event‑driven systems
• Familiarity with CI/CD pipelines, containerisation, and infrastructure‑as‑code
• Strong analytical thinking — you pull bugs back to the spec, not just the code
• Comfort with regulated environments — you think in terms of audit trails, blast radius, and data classification
• Strong proficiency in English — written and verbal
• Excellent communication skills — this role enables and mentors, not just audits. You need to teach, not agitate

Nice to have:

• Experience using observability platforms (Datadog, New Relic, Elasticsearch, Grafana) to investigate issues and validate system behaviour
• Understanding of failure modes in distributed systems (event ordering, retries, idempotency, eventual consistency)
• Knowledge of Domain‑Driven Design (DDD) — bounded contexts, ubiquitous language, aggregate boundaries

Equal Opportunity Employer

Cross River is an Equal Opportunity Employer. Cross River does not discriminate on the basis of race, religion, color, sex, gender identity, sexual orientation, age, non‑disqualifying physical or mental disability, national origin, veteran status or any other basis covered by appropriate law. All employment is decided on the basis of qualifications, merit, and business need.