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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Software Developer - **Company:** ECS Limited - **Location:** O'Fallon, IL, United States - **Experience:** Expert - **Salary:** $110,000.0 - $120,000.0 - **Contract:** Permanent contract - **Skills:** Java (Programming Language), JavaScript (Programming Language), Microsoft Windows, Agile Methodology, Apache HTTP Server, Apache Tomcat, HTML5, Automation of Tests, Bash Shell, Oracle WebLogic Server, Static Program Analysis, Code Coverage, Code Review, Continuous Integration, Linux, DevOps, Web Development, Perl (Programming Language), Entity Relationship Models, Gradle, Spring Framework, Junit, Python (Programming Language), Log Analysis, Apache Maven, Oracle Databases, Package Management Systems, Windows PowerShell, Scrum Methodology, Systems Development Life Cycle, Red Hat Enterprise Linux, Ansible, Fortify (Software), Selenium, Software Engineering, SonarQube, PL-SQL, SQL Databases, Extensible Markup Language (XML), Scripting, Test-Driven Development (TDD), ReactJS, Cypress (Programming Language), Git, SC Clearance, Build Management, Containerization, AngularJS, Kubernetes, Infrastructure Automation Frameworks, Puppet, Terraform, Cucumber (Software), Splunk, Software Version Control, Devsecops, Docker, Jenkins, Artifactory - **Published:** August 11, 2026 - **Apply:** https://www.clearancejobs.com/jobs/9085915/senior-software-developer ## About the Role ECS Federal LLC is looking for a Senior Software Developer who possesses and applies expertise on multiple complex work assignments. The ECS Team provides development and support of GATES, a mission-critical application providing cargo and passenger manifesting and in transit visibility requirements for the DoD. We are seeking a Java Developer with experience developing Web applications to be part of the larger team. Assignments may be broad in nature, requiring originality and innovation in determining how to accomplish tasks. Operates with appreciable latitude in developing methodology and presenting solutions to problems. Contributes to deliverables and performance metrics. As a Senior Software Developer, the selected individual will work hands-on with developer and systems administrators to integrate our solutions and products for our government customer. Key responsibilities are to deliver DevSecOps pipeline solutions and proof of concepts for Continuous Integration/Configuration, * Bachelor's Degree * Java, HTML5 technologies, Angular, Spring, RHEL, SQL, Oracle RDBMS, JavaScript, XML, Agile methodologies, WebLogic, Tomcat, Gradle/Maven/Ant, Python * Experience with DevSecOps pipeline * Secret Clearance * Security + Certification or the ability to obtain immediately following employment. Desired Skills * Knowledge of DoD transportation data and business practices * Ability to Design, Code and Test requirements using: + Linux and Windows operating systems + Server technologies like WebLogic, Tomcat and Apache + Container technologies like Docker, Kubernetes * Version control systems like Git * Build and deployment orchestration tools like Jenkins and K8s * Build and package managers like Gradle and Artifactory * Scripting languages such as Python, BASH, Perl, Powershell * Configuration Management tools like Ansible, Puppet, Chef, Terraform * Testing tools/frameworks like Junit, Selenium, Cucumber or Cypress * Static code analysis tools like SonarQube and Fortify * Log analytics tools like Splunk * Experience writing with Angular or React JS * Experience writing Java, JavaScript, and SQL or PL/SQL * Experience developing Infrastructure as Code (IaC) and Configuration as Code (CaC) * Familiar with Agile development methodology with an understanding of Kanban, SCRUM and SAFe® principle, and DevOps/DevSecOps processes and methods * Support troubleshooting and diagnostics in both the development and production environments * Strong understanding of test-driven development and test automation to ensure adequate test coverage (unit, integration, system, load, functional and exploratory) * Able to work with the development manager and lead architect on architecture changes and understanding process and application design including grooming requirements in the architecture that were not provided in detail or not fully defined * Ability to manage workloads and the creation of program specifications from which the developers work and add them to the work tracker adding flowcharts, class diagrams, Entity Relationship Diagrams (ERDs), and a variety of other visual techniques (mockups) to clearly convey the meaning to the developer. * Able to work with development manager to manage backlogs, estimates and other SDLC requirements for development, provide estimates on requirements for iteration/build planning, and Integrate and deploy software in a complex architecture * Able to review code, perform code reviews and code check-ins to ensure the integrity of commits, builds, etc. * Ability to learn, understand and refine the capabilities of other developers on the team including ability to mentor and coach intermediate and junior developers with constructive code reviews and code theory discussions * Good oral and written communications skills to report progress, challenges, blockers, and risks that require escalation to the development manager ## Related Videos - [Security Pitfalls for Software Engineers](https://www.wearedevelopers.com/videos/726-security-pitfalls-for-software-engineers) - [Docker network without Docker](https://www.wearedevelopers.com/videos/1418-docker-network-without-docker) - [How Unit Testing Saved My Career](https://www.wearedevelopers.com/videos/1642-how-unit-testing-saved-my-career) - [How a Small Team Shrank a Microsoft Monorepo by 94%](https://www.wearedevelopers.com/videos/1236-how-a-small-team-shrank-a-microsoft-monorepo-by-94) - [Navigating the Corporate Jungle: Life as a Developer in a large Company](https://www.wearedevelopers.com/videos/621-navigating-the-corporate-jungle-life-as-a-developer-in-a-large-company) - [Docker exec without Docker](https://www.wearedevelopers.com/videos/1094-docker-exec-without-docker) ## Related Articles - [What’s the Difference between a Junior, Mid, and Senior Developer?](https://www.wearedevelopers.com/magazine/238-what-s-the-difference-between-a-junior-mid-and-senior-developer) - [Is Software Engineering Over-Saturated?](https://www.wearedevelopers.com/magazine/418-is-software-engineering-over-saturated) - [7 Important Tips That Every Software Developer Should Know](https://www.wearedevelopers.com/magazine/101-7-important-tips-that-every-software-developer-should-know) - [How We Built a Worry-Free System That Runs for 10+ Years – And What We’d Do Again](https://www.wearedevelopers.com/magazine/751-how-we-built-a-worry-free-system-that-runs-for-10-years-and-what-we-d-do-again) - [Highest Paying Tech Companies for Developers](https://www.wearedevelopers.com/magazine/220-highest-paying-tech-companies-for-developers) - [Where to Find Entry-Level Software Engineering Jobs](https://www.wearedevelopers.com/magazine/397-where-to-find-entry-level-software-engineering-jobs)