Merchant Integration Engineer

About The Client Our client is a prominent Electronic Money Institution (EMI) dedicated to providing online payment processing solutions. They offer a comprehensive suite of services, including payment gateway services, global payment processing, merchant accounts, open banking, recurring payments, and mass payments. Catering to online businesses across a variety of sectors, they support multiple currencies and payment methods, enabling efficient global transactions.

Role Overview Join an international team as a Merchant Integration Engineer , where you will be at the forefront of ensuring seamless integrations between merchants and payment systems. This role offers the chance to work with cutting-edge APIs, diagnose complex issues, and directly influence the success of merchant integrations. The hybrid work environment based in Riga allows for a balance of remote and in-office collaboration.

Key Responsibilities

• Support and maintain integrations between merchants and payment systems.
• Diagnose integration issues by analysing logs and tracing API requests and responses.
• Reproduce bugs and prepare clear technical escalations for developers, including what was sent, what was received, and where the behaviour differs from the specification or expected result.
• Test integrations against technical specifications before go-live.
• Perform sandbox testing and verification after system or integration changes.
• Work with server-to-server REST API integrations.
• Troubleshoot asynchronous payment flows involving webhooks, callbacks, and status polling.
• Configure and troubleshoot payment plugins and modules for CMS platforms such as WooCommerce and OpenCart.
• Communicate directly with technical teams in English and/or Russian.
• Maintain integration documentation, onboarding checklists, FAQs, and common troubleshooting scenarios.
• Follow information-security requirements when working with payment and sensitive data, including proper handling of masked data, credentials, test accounts, tickets, screenshots, chats, and external services.

Requirements

• Experience in Integration Engineering, API QA, or a similar technical role.
• Strong hands-on knowledge of REST APIs, HTTP, JSON, and Postman.
• Ability to read technical documentation and existing code, troubleshoot integrations, and clearly communicate technical issues.
• Working knowledge of PHP/Laravel, JavaScript, SQL, and MySQL/MariaDB.
• Familiarity with Git, Swagger/OpenAPI, Browser DevTools, Kibana/Grafana, and Jira.
• Good understanding of information security and handling sensitive data.
• English B1+.
• Experience with payments/acquiring (3DS, webhooks, transaction statuses, payment response codes), WooCommerce/OpenCart integrations, PCI DSS, or technical customer support would be a nice to have.
• Languages: English, Russian.
• Experience in fintech.

Key Soft Skills

• Strong problem-solving mindset - able to investigate technical issues systematically and identify root causes.
• Clear communication - able to explain technical issues clearly and collaborate effectively with merchants and engineering teams.
• Attention to detail & ownership - careful with technical specifications, testing, and sensitive payment data, and takes responsibility for issues through resolution.

What We Offer

• Competitive salary aligned with experience
• Collaborative and transparent team culture
• High-impact role in a scaling fintech company
• Recognition of personal milestones and achievements
• Social benefits