Senior Java Middleware Engineer - FinTech Microservices

Okto Payments; United States; Remote; USD 120,000 - 180,000; Full time

Benefits offered by this job

Competitive compensation

Career growth

Continuous learning

Inclusive environment

Birthday leave

Job summary

OKTO's next-generation payment platform seeks a Java Middleware Engineer to design, develop, and maintain scalable backend services that process millions of financial transactions. You will collaborate with Product, Architecture, Infrastructure, QA, and Security teams to deliver secure, high-performance microservices, RESTful APIs, and robust integration with OAuth2 and other modern authentication methods.

Join a global fintech with an international engineering team, offering significant career

Qualifications

• Bachelor's degree in Computer Science, Computer Engineering, Software Engineering, Information Technology, or a related field.
• Minimum of 5 years of professional experience developing middleware or backend applications using Java.
• At least 1 year of hands-on experience with Java 11 or newer.
• Proven experience working within the FinTech, Payments, Banking, or Financial Services industry.
• Strong understanding of Object-Oriented Design (OOD), SOLID principles, and Functional Programming concepts.
• Experience designing and developing microservices architectures using Spring Boot and Spring Cloud (Netflix OSS).
• Solid knowledge of the Spring Framework 5 ecosystem.
• Experience implementing secure authentication and authorization using OAuth2.
• Experience with JPA, ORM modeling, and persistence frameworks.
• Strong experience designing and developing RESTful APIs.
• Familiarity with Event-Driven Architecture, asynchronous messaging, and distributed software design patterns.
• Experience working with Git and collaborative source control workflows.
• Good understanding of software development best practices, including unit testing, clean code principles, and code review processes.
• Strong analytical, problem-solving, and troubleshooting skills.
• Ability to work independently while collaborating effectively within an international engineering team.
• Excellent technical writing skills for documenting requirements, software designs, and technical specifications.

Responsibilities

• Design, develop, and maintain middleware applications and backend services using Java and Spring technologies.
• Develop new product features and platform capabilities based on business and technical requirements.
• Build scalable, resilient, and high-performance microservices that support payment processing and financial transaction workflows.
• Write clean, maintainable, and performance-optimized code, ensuring high-quality standards and comprehensive unit test coverage.
• Participate in the design and implementation of distributed systems and event-driven architectures.
• Develop and maintain RESTful APIs and secure service integrations using modern authentication mechanisms such as OAuth2.
• Support System Integration Testing (SIT), User Acceptance Testing (UAT), and Production environments, identifying and resolving issues to ensure platform stability.
• Collaborate with cross-functional teams, including Product Managers, QA Engineers, DevOps Engineers, and Solution Architects, to deliver high-quality software solutions.
• Participate in Agile ceremonies, code reviews, technical discussions, and knowledge-sharing initiatives.
• Contribute to continuous improvement by identifying opportunities to optimize software quality, development processes, and system performance.
• Work with version control systems and CI/CD pipelines, following engineering best practices and software development standards.
• Produce technical documentation, including product specifications, design documentation, and implementation details.

Skills

Java

Middleware/backend development

RESTful APIs

OAuth2 security

Microservices design

Spring Framework

Unit testing

Code reviews

Problem solving

Technical writing

Git workflows

Education

Bachelor's degree in Computer Science/Engineering/IT

Tools

Spring Boot

Spring Cloud

JPA ORM

Git

CI/CD

AWS

Job description

OKTO's next-generation payment platform seeks a Java Middleware Engineer to design, develop, and maintain scalable backend services that process millions of financial transactions. You will collaborate with Product, Architecture, Infrastructure, QA, and Security teams to deliver secure, high-performance microservices, RESTful APIs, and robust integration with OAuth2 and other modern authentication methods.

Join a global fintech with an international engineering team, offering significant career