Leidos is seeking a Sr. Mainframe Developer to be part of the mission solution and help lead SSA’s Digital Modernization Strategy. Join one of our high performing teams responsible for building the next-generation enterprise APIs and modern responsive user interfaces, supporting the Social Security Administration (SSA) and their mission to meet the changing needs of the public, positively impacting at least 65 million American lives per month. We are a team of forward-looking professionals in need of a strong candidate with these key required skills Strong experience with IBM z/OS (OS/390/MVS) environment developing and maintaining JCL and COBOL, Dialog Manager, Endevor, z/OS, CLIS, JCL, and DB2 for application software systems.
If this sounds like a mission you want to be a part of, keep reading!
TEAM CULTURE
Your passion and values might be a good fit for our teams if you answer “yes” to the following questions:
Are you looking for a company that puts employees first, with a focus on career, flexibility, and well-being?
Do you enjoy collaborating with colleagues and teammates and believe that the best ideas are fostered in an inclusive environment?
Are you searching for a team with a strong sense of ownership, urgency, and drive for daily mission success?
Are you comfortable with proactive outward communication and technical leadership?
Do you enjoy being a catalyst, solving complex problems, and providing innovative solutions?
Do you have the flexibility, creativity, and resilience to pivot the mission for success?
Do you have the courage to make tough ethical decisions with pride, transparency, and respect?
MENTORSHIP & CAREER GROWTH
Our teams are dedicated to supporting new team members in an environment that celebrates knowledge sharing and mentorship. Experienced team members will be assigned to new hires for one-on-one mentoring, collaborative reviews, and coaching on customer engagement to help each new hire successfully onboard and demonstrate their skills. Projects and tasks are assigned in a way that leverages your strengths and will help you further develop your skillset.
DAY TO DAY RESPONSIBILITIES
Every position we take is more rewarding when you know the why behind it. Know your work makes a difference to support those who need it most. If your passion is enabling life changing service to those around, you this is the place for you. Find you passion in a team environment where all members are valued regardless of contractor or employee status. Find your “Why” with us and take your place in our Leidos Family!!
Responsible for conforming to customer standards and requirements and will be involved in creating and maintaining code and database structures such as COBOL, Restructured Extended Executor (REXX), Job Control Language (JCL), CLIST, DB2, as well as numerous mainframe utility tools such as SYNCSORT, File-AID/Related Data XPERT (RDX), etc. Responsible for unit testing and validation against desired outcomes. The resource is expected to function as part of a team, maintain a high level of collaboration with SSA of customers, and must demonstrate excellent communication skills to ensure success.
Develop JCL and software code using customer defined standards and software engineering best practices
Evaluate impacts of database schema changes on existing software components
Investigate and repair application defects related to business logic, middleware, or database (DB2).
Design, develop, test, debug, and implement next-generation COBOL programs using software engineering, best practices and latest technologies
Create and update JCL for efficient batch processing
Evaluate the impact of new operating systems, or versions of COBOL and Endevor on programs.
Collaborate with internal teams and external vendors, offering technical advice and influencing key stakeholders to achieve strategic objectives and enhance Leidos business outcomes.
Investigate and repair application defects regardless of component: COBOL, business logic, CICS configurations, middleware, or database (PL/SQL and Data Modeling).
Brief management, customer, team, or vendors using written or oral skills at appropriate technical level for audience
All other duties as assigned or directed.
FOUNDATION FOR SUCCESS (Basic Qualifications)
Bachelor's Degree in Computer Science, Mathematics, Engineering or a related field.
Masters or Doctorate degree may substitute for required experience
10+ years of experience with Mainframe.
Must be able to obtain and maintain a Public Trust. Contract requirement.
*** Selected candidate must be willing to work on-site in Woodlawn, MD 5 days a week.
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.
April 2, 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 $107,900.00 - $195,050.00
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.

Leidos is a Fortune 500® innovation company rapidly addressing the world’s most vexing challenges in national security and health. The company's global workforce of 48,000 collaborates to create smarter technology solutions for customers in heavily regulated industries. Headquartered in Reston, Virginia, Leidos reported annual revenues of approximately $15.4 billion for the fiscal year ended December 29, 2023.
Leidos was cited for the meaningful work employees perform that is challenging, impactful, and aligned with our customers’ missions as reasons professionals want to work and stay at our company. Leidos has also been named to lists including Forbes’ Best Employers for Diversity, Forbes’ America’s Best Employers for Women, Military Times Best for Vets Employers, and Ethisphere Institute’s World's Most Ethical Companies®.
Employees enjoy career enrichment opportunities available through mobility and development and experience rewarding relationships with supportive supervisors and talented colleagues and customers. Employees appreciate our flexible work environment, allowing for and encouraging a true work-life balance. Our professionals are also excited about our Employee Resource Groups, like the Collaborative Outreach with Remote and Embedded Employees (CORE), which strives to create an environment where every employee, regardless of location, feels fully engaged as a valued employee of Leidos.
Your most important work is ahead, visit careers.leidos.com for our latest opportunities.