Java Software Engineer

Built and maintained an application scaling to millions of daily users across dozens of countries.

Collaborated with cross-functional teams on product and design.

Worked closely with product team on features like billing and user activity tracing.

Increased code quality by applying clean code principles and improving test coverage.

Developed and implemented robust security features using Spring Security, including custom authentication mechanisms, user roles and permissions management, and RBAC enforcement.

Built RESTful APIs serving frontend applications.

Designed and built software solutions for a billing, online payments, and invoicing application serving more than 2 million active users from Nordic countries.

Contributed to designing and implementing payment systems for multiple types of payments including instant, recurring, and deferred payments.

Migrated a monolith application to microservices to increase usability and prevent cascading failures.

Worked with domain-driven design, event-driven design, and onion architecture.

Participated in an Agile Scrum engineering team and supported delivery team client calls to establish technical details and change requests.

Implemented OAuth 2.0 for authentication and authorization, integrating flows such as Authorization Code and Client Credentials, configuring token validation, refresh token handling, and role-based access control (RBAC).