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I am an experienced JAVA/JEE developer with over 10 years specializing in backend API development and integration. I take pride in writing clear and maintainable code, and I have a proven track record delivering high-profile projects across both public and private sectors. I enjoy leading teams to deliver quality projects efficiently and innovating solutions that reduce downtime and streamline integrations. Throughout my career, I have worked closely with various organizations ranging from healthcare and police force to banking and telecommunications in Australia, developing scalable APIs and messaging platforms while mentoring developers. My goal is to continue evolving my skills in API-led architectures and cloud technologies while contributing to impactful projects that advance businesses and services.…I am an experienced JAVA/JEE developer with over 10 years specializing in backend API development and integration. I take pride in writing clear and maintainable code, and I have a proven track record delivering high-profile projects across both public and private sectors. I enjoy leading teams to deliver quality projects efficiently and innovating solutions that reduce downtime and streamline integrations. Throughout my career, I have worked closely with various organizations ranging from healthcare and police force to banking and telecommunications in Australia, developing scalable APIs and messaging platforms while mentoring developers. My goal is to continue evolving my skills in API-led architectures and cloud technologies while contributing to impactful projects that advance businesses and services.

Antonio Steven Nguyenjee

Developer, Back-End Developer, Programmer, +1

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I am an experienced JAVA/JEE developer with over 10 years specializing in backend API development and integration. I take pride in writing clear and maintainable code, and I have a proven track record delivering high-profile projects across both public and private sectors. I enjoy leading teams to deliver quality projects efficiently and innovating solutions that reduce downtime and streamline integrations. Throughout my career, I have worked closely with various organizations ranging from healthcare and police force to banking and telecommunications in Australia, developing scalable APIs and messaging platforms while mentoring developers. My goal is to continue evolving my skills in API-led architectures and cloud technologies while contributing to impactful projects that advance businesses and services.…I am an experienced JAVA/JEE developer with over 10 years specializing in backend API development and integration. I take pride in writing clear and maintainable code, and I have a proven track record delivering high-profile projects across both public and private sectors. I enjoy leading teams to deliver quality projects efficiently and innovating solutions that reduce downtime and streamline integrations. Throughout my career, I have worked closely with various organizations ranging from healthcare and police force to banking and telecommunications in Australia, developing scalable APIs and messaging platforms while mentoring developers. My goal is to continue evolving my skills in API-led architectures and cloud technologies while contributing to impactful projects that advance businesses and services.

Available to hire

I am an experienced JAVA/JEE developer with over 10 years specializing in backend API development and integration. I take pride in writing clear and maintainable code, and I have a proven track record delivering high-profile projects across both public and private sectors. I enjoy leading teams to deliver quality projects efficiently and innovating solutions that reduce downtime and streamline integrations.

Throughout my career, I have worked closely with various organizations ranging from healthcare and police force to banking and telecommunications in Australia, developing scalable APIs and messaging platforms while mentoring developers. My goal is to continue evolving my skills in API-led architectures and cloud technologies while contributing to impactful projects that advance businesses and services.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Work Experience

Senior JAVA/JEE Developer at eHealth NSW

December 1, 2021 - Present

Designed and implemented an asynchronous module to process and transform HL7 messages to JSON/XML and outbound them to Mirth platform. Delivered Power Billing Revenue Collection integration solutions for New South Wales Local Health Districts in Mule, capable of processing up to 200,000 FIFO messages per day. Led and mentored a team of 5 developers ensuring timely delivery and quality. Innovated an automated error-handling mechanism to decrease downtime and authored technical documentation setting company-wide integration standards.

Senior JAVA/JEE Developer at DCS NSW

December 1, 2021 - August 21, 2025

Designed and implemented an asynchronous messaging platform to integrate HealthLink, ServiceNow, and DataLake. Transformed inbound FHIR messages to HL7 and vice versa. Developed and launched 24 Mule APIs in an API-Led architecture to execute retail business microservices reusable across banking platform applications. Led migration of legacy backend apps to Mule REST APIs integrating Salesforce, ERP, and relational databases. Facilitated team knowledge sharing on MuleSoft API development.

Senior JAVA/JEE Developer at NSW Police Force

June 1, 2021 - August 21, 2025

Delivered state-wide firearm events data integration solutions. Applied integration design patterns such as Guarantee Delivery and Correlation-ID. Revised and updated API services for optimal functionality and collaborated on proprietary integration of third-party APIs to enhance product features.

Senior JAVA/JEE Developer at HSBC AU

August 1, 2020 - August 21, 2025

Delivered Retail banking APIs for HSBC NZ and HSBC AU. Led backend development for customer onboarding and credit card online applications. Mentored team members in Java Spring/Spring Boot and MuleSoft Anypoint platform.

Senior JAVA/JEE Developer at EQUIFAX AU

June 1, 2018 - August 21, 2025

Served as technical contact for API-led architecture integration solutions. Provided high-level estimates and participated in project planning. Utilized CI/CD pipelines with Jenkins, performed code refactoring, peer-reviewed code deliverables, and created functional regression tests.

Senior JAVA/J2EE Developer at HSBC AU

September 1, 2017 - August 21, 2025

Provided estimates and participated in project planning. Designed and developed new Internet Banking features per UML and design documents. Conducted peer code reviews including unit, integration, and automation tests. Independently managed changes through to production to support retail banking business.

Senior JAVA/J2EE Developer at Transport for NSW AU

March 1, 2017 - August 21, 2025

Provided high-level estimates from business requirements. Produced detailed design documents and prototypes. Developed unit, integration, and regression tests. Performed peer reviews of design and code. Documented code and deliverables. Supported team adoption of Agile Scrum methodologies.

JAVA/J2EE Developer at Telstra Bigpond NSW AU

March 1, 2013 - August 21, 2025

Estimated business as usual tasks. Created detailed design documents based on architecture designs. Designed and developed new code modules with unit, integration, and regression testing. Conducted peer reviews and supported deployment changes to production to support telecommunications business.