Sr. Appian Software Developer

Location: Washington, DC

Time Type: Full time

Job Description

Looking for an opportunity to make an impact? 

At Leidos, we deliver innovative solutions through the efforts of our diverse and talented people who are dedicated to our customers’ success. We empower our teams, contribute to our communities, and operate sustainable. Everything we do is built on a commitment to do the right thing for our customers, our people, and our community. Our Mission, Vision, and Values guide the way we do business.

If this sounds like the kind of environment where you can thrive, keep reading! 

The Digital Modernization Sector brings together our digital transformation and IT programs, allowing us to better serve our customers through scale and repeatability.

Your greatest work is ahead! 

We are looking for Senior Appian Software Engineer with 10 plus experience of software development lifecycle practices and secure coding principles.

Experience with design and delivery of complex Appian process models, SAIL (Self-Assembling Interface Layer) interfaces, records, reports, and Appian AI capabilities

Experience with API development and design and development of robust system integrations (REST/SOAP APIs, microservices) connecting Appian with disparate federal agency databases and legacy systems

5+ years of dedicated, hands-on Appian design and development experience with active Senior Developer or Lead Developer certifications

Experience operating within Agile/Scrum delivery environments, utilizing CI/CD pipelines and Git/GitLab for source control. The candidate must have:

• Bachelors Degree in Computer Science, Software Engineering or related field or Masters Degree and 6 to 10 years of related experience. Additional years of experience may be accepted in lieu of degree requirement.
• Strong written and verbal communication skills
• Ability to work independently and collaborate effectively within cross-functional Agile teams
• Experience supporting Appian platform upgrades, plugin remediation, or modernization initiatives
• Experience with implementing Appian’s Data Fabric
• Experience with data and system migrations from SQL Server or Maria Database
• Experience developing or maintaining custom Appian plugins using Java
• Familiarity with CI/CD pipelines, Jenkins, Docker, or containerized deployment approaches
• Experience supporting AWS-hosted or cloud-based application environments
• Exposure to Kubernetes or container orchestration platforms
• Exposure to Appian AI capabilities, AI Skills, AI Copilot, AI Document Processing, or other emerging Appian platform features
• Experience supporting federal government
• Experience contributing to knowledge transfer and cross-team collaboration initiatives within technical organizations

Preferred Skills

• Prior background in C# and full-stack .NET development, highly desired for custom API building and legacy system migrations.
• Hands-on experience implementing Appian AI Copilot, AI Skills, or Intelligent Document Processing (IDP).
• Prior delivery experience within federal civilian or DoD environments
• Appian Senior Developer or Lead Developer Certification

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:

June 29, 2026

Pay Range:

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.