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# Java/.net Modernization Engineer

- **Company:** Koniag Services, Inc.
- **Location:** Washington, DC, United States
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** ASP.NET, Java (Programming Language), .NET Framework, Application Programming Interfaces (APIs), Amazon Web Services, Amazon S3, User Authentication, Automation of Tests, C Sharp (Programming Language), Information Systems, Continuous Integration, Data Centers, Data Migration, Data Security, Relational Databases, Oracle (Applications), Secure Coding, Enterprise Software Applications, SOAPAPI, Appian, Information Technology, Low-code, Code Restructuring, Devsecops
- **Published:** October 30, 2026
- **Apply:** https://www.clearancejobs.com/jobs/9278774/javanet-modernization-engineer

## About the Role

* Bachelor's degree in computer science, engineering, information systems, or a related field; additional relevant experience may substitute for education.
 * Five or more years of enterprise software engineering experience using Java, .NET/C#, or both.
 * Experience modernizing legacy applications, decomposing tightly coupled services, and preserving APIs, business rules, and data behavior.
 * Experience with relational databases, REST/SOAP services, secure coding, automated testing, CI/CD, and production troubleshooting.
 * U.S. citizenship and the active security clearance or eligibility required for the assigned work by the start of performance, with ongoing eligibility thereafter.
 * Ability to communicate clearly with Government, technical, and business stakeholders and to maintain accurate work records in approved systems.
 * Ability to protect Controlled Unclassified Information and classified information, when assigned, and comply with required access, training, and handling procedures.

Education and Experience Desired:

 * Experience integrating conventional code with Appian or another low-code platform.
 * Experience with Spring, ASP.NET, containers, AWS, Oracle, S3, or enterprise document and reporting systems.
 * Experience modernizing Federal acquisition, financial, or other regulated applications., * Java and .NET enterprise development
 * Legacy analysis and incremental refactoring
 * API facades and compatibility engineering
 * Automated testing and secure DevSecOps
 * Migration, cutover, and production support

## Description

Tuknik Government Services, LLC, Koniag Government Services (KGS) is seeking qualified candidates for this role supporting our U.S. Army customer on a large-scale Army contracting systems modernization and automation program. Analyzes and decouples legacy Java and .NET components supporting solution integrations. The engineer preserves required behavior and interfaces while helping the team retain, wrap, refactor, replace, or retire each component through controlled migration waves. This is a contingent recruiting profile; the opening, employing subsidiary, compensation, work location, and staffing remain subject to final contract authorization.

Essential Functions, Responsibilities & Duties may include, but are not limited to:

 * Inventory legacy Java and .NET applications, services, libraries, jobs, interfaces, dependencies, configurations, and operational procedures.
 * Trace business rules, calculations, transformations, data access, authentication, error handling, and external dependencies in legacy code.
 * Recommend retain, wrap, refactor, replace, or retire dispositions based on mission need, security, supportability, performance, and lifecycle cost.
 * Develop API facades and compatibility adapters that preserve external contracts while target Appian capabilities transition.
 * Refactor approved services into modular, testable components or bounded external services where Appian-native implementation is not appropriate.
 * Eliminate unsupported libraries, embedded credentials, obsolete protocols, and high-risk custom code through approved designs.
 * Create unit, integration, contract, regression, and security tests that compare modernized behavior with the legacy baseline.
 * Support data migration, parallel operation, deployment, cutover, rollback, stabilization, and legacy retirement.
 * Package code through the approved DevSecOps pipeline and resolve code-quality, dependency, vulnerability, and licensing findings.
 * Maintain technical designs, interface specifications, dependency maps, release notes, and operational documentation.