Java Developer (Belfast)

MiFinity; Belfast City District; Hybrid; GBP 52,000 - 90,000; Full time

Job summary

MiFinity is expanding its Belfast team to build scalable backend systems for payments and eWallet services. You will design APIs, implement distributed Java services, and ensure reliability across high-transaction workloads.

The role covers the full development lifecycle—from whiteboard architecture with stakeholders to delivering clean, well-tested code and collaborating with cross‑functional teams to improve performance and resilience.

Responsibilities

• Develop new in-house products
• Translate application storyboards and use cases into feasible functional applications
• Design, build, and maintain efficient, reusable, and reliable Java code
• Write clean code supported with unit testing modules
• Ensure the best possible performance, quality, scalability and responsiveness of the applications
• Document features and share knowledge within the team
• Collaborate with other team members and stakeholders
• Help maintain code quality, organization, and automatization including undertaking peer code reviews
• Perform integrations with 3rd party applications

Job description

MiFinity is a dynamic, licensed, and regulated fintech leader offering cost-effective, end-to-end payment solutions for businesses, merchants, and consumers. With over 20 years of experience in online payments, we have built a highly secure technology platform and a growing global network of financial and banking partners. Our core service, the MiFinity eWallet, enables seamless money transfers worldwide through our extensive bank network and local payment options. As we continue to expand across multiple global verticals, we foster a collaborative, inclusive work environment while maintaining a start-up culture that values flexibility, autonomy, and innovation across all of our offices in Dublin, Malta, and Belfast.

Role summary

You’ll be working on the backend of systems that move money; payment processing engines, merchant integration services, and the microservices that orchestrate transactions across multiple payment rails. This means designing APIs that handle edge cases gracefully, building services that fail safely when things go wrong, and ensuring our platform can scale as transaction volumes grow. We’re looking for someone who is comfortable in the full lifecycle; from whiteboarding a technical approach with stakeholders, to writing clean Java code that other developers will maintain, to debugging production issues when required. The ideal candidate is someone who has built distributed systems before and understands the trade-offs between consistency and availability. We’re looking for someone who spots problems in the design phase, and who cares about getting it right.

Responsibilities

• Develop new in-house products
• Translate application storyboards and use cases into feasible functional applications
• Design, build, and maintain efficient, reusable, and reliable Java code
• Write clean code supported with unit testing modules
• Ensure the best possible performance, quality, scalability and responsiveness of the applications
• Document features and share knowledge within the team
• Collaborate with other team members and stakeholders
• Help maintain code quality, organization, and automatization including undertaking peer code reviews
• Perform integrations with 3rd party applications