Senior Software Engineer – Go / Node.js

CONCEPT SOLUTIONS LLC•Reston, VA

4d•$170,000 - $180,000•Remote

About The Position

Concept Solutions, LLC (CS) is seeking an experienced Senior Software Engineer to build, modernize, and sustain mission-critical applications for a Department of War customer. The role focuses on developing, enhancing, and maintaining high-volume, public-facing applications while supporting secure cloud operations and application modernization. The successful candidate will bring strong backend engineering expertise in Node.js or Go, experience supporting production applications, and a commitment to reliable, secure, and scalable software. The position is remote and full-time, with a 40-hour workweek from Monday through Friday and core hours of 9:00 a.m. to 3:00 p.m. Eastern. Work follows two-week Agile sprints, including customer demonstrations each sprint. Travel is 0–10% within the Washington, DC metropolitan area. U.S. citizenship is required. This is a privileged-access position; candidates must hold a current favorably adjudicated Tier 5 investigation or Top Secret clearance, or be eligible to obtain one. An active clearance may allow for an earlier start. The annual compensation range is $170,000–$180,000, depending on experience. Concept Solutions offers health, dental, vision, and life insurance, plus a comprehensive 401(k) plan with matching and immediate vesting.

Requirements

At least 7 years of professional backend software engineering experience, including at least 3 years of production experience with Node.js (JavaScript/TypeScript) or Go (Golang).
Strong experience developing and maintaining REST APIs.
Hands-on experience with SQL and PostgreSQL databases.
Experience operating and supporting production applications in cloud environments.
Knowledge of formal change control processes and privileged-access security requirements.
Demonstrated ability to troubleshoot production issues, implement fixes, and support application releases.
U.S. citizenship.
Must hold a current favorably adjudicated Tier 5 investigation or Top Secret clearance, or be eligible to obtain one.

Nice To Haves

Production development experience with both Node.js and Go.
Experience with React and TypeScript.
Familiarity with Amazon ECS or Kubernetes for container orchestration.
Experience supporting applications in AWS GovCloud environments.
Experience integrating applications with identity providers using OIDC or SAML.
A current favorably adjudicated Tier 5 investigation or active Top Secret clearance, which may enable earlier access.

Responsibilities

Sustain and enhance high-volume, public-facing web applications, resolve defects, apply security patches, and deliver releases under formal change control processes.
Develop and maintain backend services using Node.js and Go, with React/TypeScript front-end applications and PostgreSQL databases.
Support containerized application deployments in cloud environments.
Integrate applications with identity providers and shared platform services.
Maintain technical documentation, operational runbooks, and application sustainment procedures.
Participate in on-call rotations to support production application availability and incident resolution.
Identify and remediate security findings, address vulnerabilities, and maintain current software dependencies.
Collaborate with engineering and operations teams to ensure application reliability, performance, and security.
Participate in two-week Agile sprints and customer demonstrations.