WebSphere & API Integration Engineer
(Mainframe WebSphere & API Integration Engineer) Work Authorization: U.S. Citizens Only Location: Remote Position Overview Zenius is seeking an experienced WebSphere Application Server (WAS) and API Integration Subject Matter Expert to support a federal government client's Mainframe Operations and Application Support environment. This position combines WebSphere Application Server administration and API development responsibilities, supporting enterprise middleware, API integration, HATS-based services, and application connectivity within the client's IVR and mainframe ecosystem. The selected candidate will be responsible for maintaining, troubleshooting, and enhancing enterprise application services, middleware components, and HATS-based API integrations within the client environment.
Key Responsibilities
Provide administration, configuration, maintenance, and operational support for IBM WebSphere Application Server (WAS) environments. Support and maintain HATS-based APIs transforming 3270/5250 mainframe applications into RESTful services. Troubleshoot and resolve WebSphere, API, middleware, and integration-related issues. Perform WebSphere health checks, performance analysis, and tuning. Maintain and update HATS macros, Integration Objects, RESTful service files, and related API components. Support API testing, validation, troubleshooting, and regression testing using tools such as Postman. Collaborate with cross-functional infrastructure, mainframe, application, and operations teams to support enterprise integrations. Support integration of WebSphere and API services within the software development and deployment lifecycle. Assist with DevOps, automation, and operational improvement initiatives where applicable. Develop and maintain technical documentation, operational procedures, configurations, and knowledge transfer materials. Participate in root cause analysis, incident resolution, change implementation, and post-implementation support activities. Provide technical guidance, operational recommendations, and knowledge transfer to project and customer teams. Support secure API and middleware practices, including SSL/TLS and authentication/security integration.
Required Qualifications
And Experience Bachelor's degree in Computer Science, Information Technology, or a related field. Minimum 5 years of experience supporting WebSphere Application Server and enterprise middleware environments. Minimum 5 years of experience in API development/support within enterprise environments. Strong knowledge of IBM WebSphere Application Server architecture, installation, configuration, administration, and troubleshooting. Experience with IBM Host Access Transformation Services (HATS). Proficiency in Java / Java EE and RESTful API development concepts. Experience with API testing and documentation tools such as Postman and Swagger. Strong understanding of enterprise integration, middleware, distributed systems, and web services. Experience supporting application performance tuning and operational optimization. Familiarity with DevOps, CI/CD, and automation concepts. Strong problem-solving, troubleshooting, and analytical skills. Strong communication and collaboration skills supporting cross-functional teams. Preferred Qualifications (Nice To Have) Experience with Docker and Kubernetes. Familiarity with API security standards (OAuth, JWT, SSL/TLS). Experience with Jenkins, Git, RAD, or other DevOps tooling. Familiarity with API management platforms such as Apigee, Kong, or MuleSoft. Experience supporting enterprise environments within federal or regulated industries. IBM WebSphere-related certifications. Experience with event-driven architectures and messaging technologies. 7 10+ years of overall enterprise middleware/API support experience. Additional Required Skills Microsoft Excel Microsoft Word Rational ClearQuest Rational ClearCase CMMI Level 3 Excellent verbal and written communication skills About The Company Headquartered in Leesburg, Virginia, Zenius Corporation is a HUBZone-certified small business. Zenius specializes in providing Grants Management, IT Modernization, Acquisition Management, and Financial Management services to Federal agencies. Zenius is selected by Inc 5000 as one of the fastest-growing companies in the DC Metro Area, awarded in 2025, 2024, 2021, and 2020. Zenius is also listed by Financial Times as one of the fastest-growing companies in the Americas in 2021. Zenius is an awardee of 2019 Best of Leesburg winner (Business Management Consultant category).
Benefits
Zenius Corporation is an employee-oriented company. Join us now and help us grow! We offer a competitive benefits package that includes paid holidays and paid time off, medical insurance including health, vision, dental insurance, 401K matching, Flexible Spending Account and flexible schedules, as per business needs. We also work with our employees on training and professional certification plans that benefit the employee. Equal Opportunity Employer Zenius Corporation provides equal employment opportunities (EEO) to all employees and applicants for employment without regard to race, color, religion, gender, sexual orientation, gender identity or expression, national origin, age, disability, genetic information, marital status, amnesty, or status as a covered veteran in accordance with applicable federal, state, and local laws. Zenius complies with applicable state and local laws governing non-discrimination in employment in every location in which the company has facilities. This policy applies to all terms and conditions of employment, including, but not limited to, hiring, placement, promotion, termination, layoff, recall, transfer, leaves of absence, compensation, and training. Zenius Corporation expressly prohibits any form of unlawful employee harassment based on race, color, religion, gender, sexual orientation, gender identity or expression, national origin, age, genetic information, disability, or veteran status.