Senior Full Stack Engineer — Modernize Legacy Systems Remote

Lightfeather Io Llc; United States; Remote; USD 90,000 - 115,000; Full time

Job summary

LightFeather IO LLC is seeking a Senior Full Stack Engineer to support a federal government client, owning end-to-end delivery and translating complex legacy behavior into a modern platform-based solution. The role is remote (EST hours) with a focus on designing, developing, and integrating backend services, APIs, and front-end components, while collaborating with stakeholders and following best practices.

Qualifications include 7+ years of hands-on experience, US citizenship clearance, and

Qualifications

• U.S. Citizenship with ability to obtain Public Trust clearance.
• Bachelor's degree in Computer Science or related field (or equivalent experience).
• 7+ years of hands-on full stack software development experience.
• Experience in complex/enterprise system environments.
• Strong experience with Java and Spring Boot.
• Experience designing and implementing RESTful APIs.
• Experience with relational databases and data access patterns.
• Ability to troubleshoot across multiple layers of an application stack.
• Experience in Agile or iterative delivery environments.
• Ability to analyze and simplify complex systems and workflows.
• Strong systems thinking and problem-framing capability.
• Comfort working in ambiguous, poorly documented environments.
• Ability to distinguish essential functionality from legacy bloat.
• Ownership mindset and accountability.
• Effective communication with technical and non-technical stakeholders.
• High learning agility and willingness to adopt new platforms and tools.

Responsibilities

• Design, develop, and maintain full stack applications supporting modernization of systems.
• Analyze legacy systems and workflows to identify core functionality vs. overhead.
• Translate operational requirements into scalable, modern design.
• Develop backend services, APIs, and integration layers linking legacy to modern platforms.
• Build and enhance user-facing components with modern front-end tech.
• Support the full SDLC: analysis, design, development, testing, deployment, maintenance.
• Troubleshoot issues across application, integration, and data layers.
• Collaborate with stakeholders to clarify requirements and improve behavior.
• Participate in code reviews and uphold engineering best practices.

Skills

Java & Spring Boot

RESTful APIs

Relational databases

Agile delivery

Systems thinking

Ownership mindset

Communication skills

Learning agility

U.S. Citizenship

Problem solving

Education

Bachelor's degree in Computer Science or related field

Job description

LightFeather IO LLC is seeking a Senior Full Stack Engineer to support a federal government client, owning end-to-end delivery and translating complex legacy behavior into a modern platform-based solution. The role is remote (EST hours) with a focus on designing, developing, and integrating backend services, APIs, and front-end components, while collaborating with stakeholders and following best practices.

Qualifications include 7+ years of hands-on experience, US citizenship clearance, and