Senior Software Engineer – Full Stack Java
Confirmed on the employer's own hiring board on Sep 30, 2026. First seen by Alion on Sep 28, 2026.
About Four Sea Group, Inc.
Four Sea Group is a 100% employee-owned technical mission support company based in Denver, Colorado. Founded by an aerospace industry veteran and PhD astrophysicist, we support complex defense, space, software, systems, and mission-focused programs for government and industry partners. What sets FSG apart is the caliber of our people and the way we operate: we are a reputation-driven team of highly skilled engineers and technical experts who are brought in for their depth, judgment, and ability to solve difficult problems. As an employee-owned company, we have built our compensation, benefits, and culture around a simple idea: when the company succeeds, that value should go back to the people doing the work.
About the role
Four Sea Group is seeking a Senior Software Engineer to develop and support modern full-stack software capabilities for secure customer missions. This role will contribute to Four Sea Group’s ability to deliver reliable, maintainable software by independently developing application features and services, resolving technical issues, and supporting integration across frontend, backend, data, and deployment environments.
The ideal candidate brings strong Java development experience along with practical frontend, database, Linux, and collaborative development skills. This role is well suited for an engineer who can independently deliver within a defined technical scope, learn unfamiliar technologies quickly, and work with attention to quality and detail in a mission-focused engineering environment.
Required Qualifications
- Bachelor’s degree in Computer Science, Software Engineering, Computer Engineering, or a related technical field, or equivalent practical experience.
- Typically six or more years of relevant software engineering experience.
- Active DoD TS/SCI security clearance required at the time of application
- Strong experience developing applications with Java and Spring.
- Experience developing user-facing applications with Angular or Vue.
- Experience using Git-based version control in collaborative software-development environments.
- Experience with Maven or comparable software build and dependency-management tools.
- Experience working with artifact repositories such as Nexus or comparable platforms.
- Experience developing applications that interact with document-oriented databases including Elasticsearch and MongoDB.
- Experience developing and troubleshooting software in Linux environments.
- Ability to independently develop, test, troubleshoot, and deliver software within an assigned technical scope.
- Ability to quickly learn unfamiliar technologies, tools, and program environments.
- Strong attention to detail and commitment to reliable software delivery.
- Strong written and verbal communication skills.
Preferred Qualifications
- Experience developing software for U.S. government, defense, intelligence, or other secure mission environments.
- Experience developing and consuming RESTful APIs or microservices.
- Experience with CI/CD pipelines and automated software delivery.
- Experience with Docker, Kubernetes, or other containerized application environments.
- Experience working across frontend, backend, integration, and test teams.
- Experience within Agile or SAFe software-development environments.
Salary: The salary range for this role is $104,000- $160,700per year. The salary range provided is a good faith estimate representative of all experience levels. Four Sea Group, Inc. considers several factors when extending an offer, including but not limited to, the role, function and associated responsibilities, a candidate’s work experience, location, education/training, key skills, and market conditions.
Application Deadline: This position is expected to remain open through October 30, 2026. The company may adjust this deadline based on business needs and will update the posting as appropriate.
Benefits: FSG is 100% ESOP-owned, which means our employees share directly in the company’s growth. We offer competitive compensation, a strong employer-funded retirement plan, generous PTO and flexible time-off options, comprehensive health, dental, vision, life, short-term disability, and long-term disability benefits, plus a generous medical stipend that gives employees more choice and flexibility. Our model is intentionally built to keep more value with employees through salary, retirement, benefits, and ownership. You will work alongside experienced engineers and technical leaders on meaningful defense, space, software, systems, and mission support work, with room to grow as a technical expert, mentor, program contributor, or future leader.
EEO Statement: Four Sea Group is an equal opportunity employer and considers qualified applicants for employment without regard to race, color, sex, sexual orientation, gender identity or expression, religion, national origin, marital or familial status, age, disability, veteran status, military service or application for military service.