Sr. Software Engineer TS/SCI Poly

Leidos LLC; Alexandria (VA); On-site; USD 131,000 - 237,000; Full time

Job summary

Leidos LLC is seeking a Senior Software Engineer with an active TS/SCI polygraph to drive software development across the full lifecycle for a large enterprise system.

You will work within an Agile team, perform development, unit testing, integration, and deployment, and contribute to automated testing using DevOps tooling and BDD patterns. Proficiency in Java, Python, and C/C++ is required, with web/UI and cryptographic knowledge preferred.

Qualifications

• BS degree and 12–15 years of relevant experience or MS with 10–13 years of relevant experience.
• Demonstrated experience with Java and multiple Java frameworks (Spring, JEE, Jackson, Jersey).
• Proficiency with languages such as Javascript, Python, C/C++, Groovy, SQL.
• Experience with IDEs (Eclipse, VS Code, Visual Studio, WebStorm).
• Experience with databases (Oracle, PostgreSQL, MongoDB, SQL Server).
• Experience with web UI development (AngularJS, HTML, XML, XSLT) and web services.

Responsibilities

• Participate in daily stand-ups, Sprint Planning and PI Planning, and related team activities.
• Analyze complex system requirements and design solutions using formal specifications and data flow diagrams.
• Ensure code is modular, efficient, reliable, and reusable across programs.
• Engineer and document automation scripts and deploy to test/production environments.

Skills

Java

Python

C/C++

Cryptography concepts

Web technologies

DevOps automation

BDD

Agile methodologies

Software testing

Education

BS degree

Master's degree

Tools

Eclipse

Visual Studio Code

WebStorm

Spring Framework

JEE (JPA, EJB, JTA, Servlet)

Tomcat/WebLogic/JBoss

Jenkins

Docker/Kubernetes/OpenShift

SQL/NoSQL databases

Job description

Job Description Leidos has an exciting opportunity for a Sr. Software Engineer! *Must have an active TS/SCI Polygraph up front. No exceptions.* You will perform software development lifecycle (SDLC) activities as both an individual and a member of our top-notch agile development team building a large complex enterprise system. Development includes the full range of turning Agile user stories into implementable concepts, through development, unit testing, integration and test, and deployment of the new capabilities for the large complex enterprise system. Following the Behavior-driven Development (BDD) pattern, developers are responsible for implementing robust testing leveraging DevOps automation and, where appropriate, use of test automation commercial tools. There are a range of opportunities for server-side business logic implementation as well as client web application and user interface (UI) development. Java, Python, embedded C/C++, Java cryptographic framework, XML, web UI (i.e., Angular, JavaScript, CSS, HTML, etc.) and special purpose device programming opportunities are available.

Primary Responsibilities

You will actively participate in daily stand-ups, Sprint Planning, Program Increment (PI) Planning, and other related team activities; analyze and study complex system requirements, use design software tools, provide support using formal specifications, data flow diagrams, and other accepted design techniques and will use sound software engineering principles to ensure that developed code is modifiable, efficient, reliable, understandable, fault tolerant, and reusable. You will provide software process management and control throughout the coding portion of the software development process and will promote code reuse and cross-program collaboration while reducing maintenance costs by creating common functions and shared actions for developers and testers. You will engineer, author, tune and document automation scripts in a development environment and deploy to the test/production bench.

Basic Qualifications

• Must have a BS degree and 12 – 15 years of prior relevant experience or Masters with 10 – 13 years of prior relevant experience. Additional experience may be substituted for a degree.
• Must have demonstrated experience with Java.
• Must have experience or familiarity with multiple Java frameworks: Spring to include Boot and Data, Java Enterprise Edition (JEE) (i.e., JPA, EJB, JTA, Servlet), Jackson, Jersey, Swing, JavaFX.
• Must have experience or familiarity with multiple of the following languages such as Javascript, Python, C/C++, Groovy, Structured Query Language (SQL).
• Must have experience with development IDEs (Integrated Development Environments) such as Eclipse, Visual Studio Code, Visual Studio, Rhapsody, WebStorm.
• Must have experience with databases such as Oracle, PostgreSQL, MongoDB, SQL Server.
• Must have experience with Web Application User Interface Development, knowledge of databases and structures, Spring Framework, and/or experience working with AngularJS, JSON, HTML, XML, XSLT.
• Must have experience with software source control and configuration management tools.
• Must have experience with technologies underlying cryptographic systems (symmetric and asymmetric cryptography, ASN.1 encoding, XML canonicalization, digital signatures).
• Must have experience developing on Windows, and/or Linux operating systems.
• Must have documented professional experience with web services.
• Must have a strong understanding of sound software development principles and practices.
• Must be able to plan and prioritize personal tasking and be able to communicate effectively verbally and in writing.
• Must be an independent thinker, capable of performing high quality work, both independently and with a team in a fast-moving environment.

Preferred Qualifications

• Experience with the following: Java Enterprise Edition (JEE) (i.e., EJB, JPA, JTA, JAX-B, JAX-RS, JAX-WS), SQL, application servers (Tomcat, WebLogic, JBoss), Spring framework, scripting.
• Experience or familiarity with multiple of the following technologies: XML/XSD/SOAP/WSDL/XSLT, REST, JSON, YAML, Containers (Docker, Podman, Kubernetes, OpenShift).
• Experience with Javascript frameworks: AngularJS, Bootstrap, JQuery.
• Experience with Testing and Mocking frameworks: JUnit, Jupiter, Mockito, Jasmine, Karma, Cucumber, Unified Functional Tester (UFT), Selenium, FITNesse.
• Experience with build tools: Maven, CMake, RPM, Jenkins, Nexus.
• Experience with high level requirements management including requirements decomposition, secure systems engineering and development, trade-off analysis, interface control, and testing and continuous integration.
• Experience in software development on Agile teams using Agile Developer practices such as Pair Programming, Test Driven Development (TDD), Refactoring, and Acceptance Test Driven Development (ATDD).
• Experience with Behavior Driven Development (BDD).
• Secure Software development (i.e., Layer 7 Policy).
• Experience with the Scrum, Scaled Agile Framework (SAFe) methodology, SAFe Agilest Certification, or experience as a member of an Agile team.

If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo - because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 - and moving faster than anyone else dares.

Original Posting

April 27, 2026 For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above.

Pay Range

Pay Range $131,300.00 - $237,350.00 The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.

Pay and Benefits

Pay and benefits are fundamental to any career decision. That's why we craft compensation packages that reflect the importance of the work we do for our customers. Employment benefits include competitive compensation, Health and Wellness programs, Income Protection, Paid Leave and Retirement. More details are available here.

Securing Your Data

Leidos will never ask you to provide payment-related information at any part of the employment application process. And Leidos will communicate with you only through emails that are sent from a Leidos.com email address. If you receive an email purporting to be from Leidos that asks for payment-related information or any other personal information, please report the email to [e-mail].

Commitment and Diversity

All qualified applicants will receive consideration for employment without regard to sex, race, ethnicity, age, national origin, citizenship, religion, physical or mental disability, medical condition, genetic information, pregnancy, family structure, marital status, ancestry, domestic partner status, sexual orientation, gender identity or expression, veteran or military status, or any other basis prohibited by law. Leidos will also consider for employment qualified applicants with criminal histories consistent with relevant laws.

Company Overview

Leidos is an industry and technology leader serving government and commercial customers with smarter, more efficient digital and mission innovations. Headquartered in Reston, Virginia, with 47,000 global employees, Leidos reported annual revenues of approximately $17.2 billion for the fiscal year ended January 2, 2026. For more information, visit www.Leidos.com.