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# Mid-Level Software Engineer

- **Company:** Leidos, Inc.
- **Location:** St. Louis, MO, United States
- **Experience:** Experienced
- **Salary:** $87,100.0 - $157,450.0
- **Contract:** Permanent contract
- **Skills:** Clean Code Principles, Java (Programming Language), JavaScript (Programming Language), Agile Methodology, Apache Tomcat, Software Applications, Software Bug Management, Cloud Computing, Software Quality, Code Review, Data Validation, Relational Databases, Database Development, Database Queries, Software Debugging, Linux, Python (Programming Language), PostgreSQL, Linux System Administration, Apache Maven, Object-Oriented Software Development, OpenShift, Software Engineering, SQL Databases, Web Application Frameworks, Spring-boot, Backend, Containerization, Gitlab-ci, Information Technology, Front End Software Development, Database Backup, Restful APIs, Docker
- **Published:** May 19, 2026
- **Apply:** https://www.indeed.com/viewjob?jk=1c5db29ef4be7479

## About the Role

We are seeking a motivated and skilled Software Engineer (T3) to support the development and delivery of scalable software solutions within our engineering organization. This role focuses on implementing high-quality code, supporting system functionality, and contributing to team-based software development efforts.

The ideal candidate possesses strong object-oriented programming fundamentals, backend development experience, and the ability to work effectively within a collaborative engineering environment. This individual will contribute to software enhancements, troubleshoot issues, and support ongoing development activities across the software development lifecycle.

Clearance Level Required:

TS/SCI, and ability to obtain a Polygraph., * US citizenship is required per contract.

 * Bachelor's degree in Computer Science, Software Engineering, or related field with 4-8 years of relevant experience or Master's degree with 2-6 years of relevant experience.
 * Java or Python: Professional experience developing object-oriented applications.
 * REST APIs: Experience developing or maintaining RESTful services.
 * SQL: Experience writing queries and working with relational databases.
 * Linux: Working knowledge of Linux environments.
 * Ability to work independently on defined tasks within established technical frameworks.

Preferred Qualifications:

 * JavaScript: Exposure to front-end development.
 * GitLab CI/CD: Experience working within CI/CD pipelines.
 * Containerization: Familiarity with Docker or OpenShift.
 * Exposure to cloud-based environments.
 * Experience with modern web frameworks.
 * Experience with Spring Boot, PostgreSQL, Tomcat, or Maven.
 * Experience working in Agile development environments.

#MARU

## Description

* Object-Oriented Programming: Develop, test, and maintain software applications using object-oriented design principles.
 * REST API Development: Implement and support RESTful services under established architectural guidance.
 * Database Development: Write and maintain SQL queries; support database updates and data validation efforts.
 * Linux Environments: Develop and troubleshoot applications within Linux-based environments.
 * Bug Fixing & Enhancements: Identify, debug, and resolve application-level defects and performance issues.
 * Team Collaboration: Work closely with senior engineers and team members to implement approved designs and deliver project requirements.
 * Code Quality: Follow established coding standards, participate in code reviews, and support documentation efforts. .


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