Senior QA Engineer

SLEM Technologies; United States; Remote; USD 120,000 - 180,000; Full time

Job summary

SLEM Technologies in the United States is seeking a hands-on QA lead to own quality strategy for payment systems that integrate with MPGS and Visa Cybersource. You will drive risk-based testing across checkout, authentication, settlement, and reconciliation, guiding teams to release readiness and financial accuracy.

This role requires five-plus years in fintech QA, strong automation skills with Playwright, Cypress or Selenium, and deep knowledge of payments lifecycles, 3-D Secure, tokenisation,

Qualifications

• 5+ years in software QA with fintech/payments testing.
• Hands-on integration testing with MPGS and Visa Cybersource.
• Strong automation skills with Playwright, Cypress or Selenium.
• Deep knowledge of card payments lifecycles and reconciliations.
• Experience testing payment APIs and SQL data checks.
• PCI DSS-aware testing and secure test data handling.
• Experience owning test strategy and mentoring others.

Responsibilities

• Define payment test strategy and integration acceptance criteria.
• Automate checks for checkout, 3-D Secure, tokenisation, authorisation, capture, refunds.
• Test duplicates, delays, timeouts, retries, and concurrency.
• Validate ledgers, settlement reports, and dispute workflows.
• Lead performance and resilience testing and ensure logs do not contain sensitive data.
• Investigate incidents and support other QA engineers.

Skills

QA strategy

Automation testing

Playwright

Cypress

Selenium

SQL

PCI DSS

Test coordination

Tools

MPGS

Visa Cybersource

k6

JMeter

Job description

Role overview

Own quality strategy for payment systems that integrate with MPGS and Visa Cybersource, bringing hands-on testing experience with both gateways and a strong background in systems handling real financial transactions. Lead risk-based testing across checkout, authentication, transaction processing, refunds, settlement, and reconciliation, helping teams assess release readiness and prevent financial errors.

Responsibilities

• Set payment test strategy, define gateway sandbox coverage and integration acceptance criteria, and assess release risks.
• Automate checks for checkout, 3-D Secure, tokenisation, authorisation, capture, voids, refunds, and transaction statuses.
• Test duplicate requests, delayed or repeated notifications, timeouts, retries, and concurrent transactions.
• Validate transaction and ledger records, settlement reports, reconciliation results, and dispute workflows for financial accuracy.
• Lead performance and resilience testing, and check that sensitive payment data is absent from logs and test evidence.
• Investigate payment incidents, communicate financial and operational risks, and support other QA engineers.

Requirements

• At least five years in software quality assurance, including substantial fintech or payments testing experience.
• Hands-on integration and end-to-end testing with both MPGS and Visa Cybersource.
• Strong automation skills with Playwright, Cypress, or Selenium.
• Deep knowledge of card-payment lifecycles, 3-D Secure, tokenisation, refunds, settlement, reconciliation, and chargebacks.
• Experience testing payment APIs, checking financial data with SQL, and investigating failures across distributed transactions.
• Working knowledge of PCI DSS-aware testing, secure test data, and payment security controls.
• Experience owning test strategy and supporting other testers.

Nice to have

• Payment load or resilience testing with k6 or JMeter.
• Experience with acquiring-bank certification, fraud rules, or multi-currency payment testing.