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Senior Java Engineer - Onsite

MSYS Inc.Washington, DC🇺🇸United StatesPosted Sep 28, 2026

Quick Overview

Seniority
Mid Senior
Work mode
On Site
Location
Washington, DC, United States
Posted
Yesterday
DockerMicroservicesMySQLRubySpringSpring BootAWSEncryptionOAuthGitGraphQLHelmHibernateJavaKubernetesPostgreSQLREST

Job Description

Title:Senior Java Engineer - Onsite
Location:Washington, DC
Length:Long term
Restriction:w2 only
Description:

 Job Description

The Senior Java Engineer will lead the design, development, migration, and support of scalable Java-based microservices and APIs in a modern cloud environment. This role requires strong hands-on engineering capability, technical leadership, and experience modernizing legacy systems.

Responsibilities

  • Plan and execute migration from legacy monolithic code to modern, scalable Java-based microservices without disrupting live systems.
  • Lead API design and development, including specifications, endpoints, data models, and protocols such as REST and GraphQL.
  • Lead data strategy and migration of shared databases into service-specific data layers while maintaining data integrity.
  • Identify and resolve data or system bottlenecks early in the development lifecycle.
  • Deploy and operate workloads on Kubernetes in AWS, including deployment manifests, Helm, scaling, rollouts, and resource requests/limits.
  • Tune and optimize databases through query performance tuning, indexing strategy, connection pooling, migration strategy, and caching patterns.
  • Write production-grade code for core services and remain deeply involved in the codebase.
  • Ensure seamless API integration with internal systems, external systems, applications, and third-party services.
  • Promote adoption of AI in the API development lifecycle, including use of GitHub Copilot for coding.
  • Implement authentication, authorization, encryption, and other security best practices to protect data and services.
  • Monitor and optimize API performance, scalability, and reliability.
  • Support on-call operations.

Qualifications

Skills

  • 8+ years of experience leading technical teams in building scalable modern Java services.
  • Proven experience breaking down large, complex legacy monoliths into smaller, independent services.
  • Deep hands-on knowledge of modern Java, Spring Boot, Hibernate, and REST API development.
  • Experience with relational databases such as PostgreSQL or MySQL.
  • Strong experience designing, building, and maintaining APIs.
  • Ability to lead engineering teams while remaining hands-on with development.
  • Experience with Docker, Kubernetes, and Helm.
  • Familiarity with application security principles and secure development practices.
  • Familiarity with Git version control.
  • Familiarity with OAuth.
  • Ruby-to-Java migration experience preferred, but not required.

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