Expert Application Developer

Cornerstone Defense LLC; Hanover (MD); On-site; USD 235,000 - 255,000; Full time

Job summary

Cornerstone Defense LLC is seeking an Expert Applications Developer to design, develop, and maintain backend libraries and integration services. The role emphasizes Java with occasional Python, focusing on data ingestion, transformation, and standardization across multiple applications.

Responsibilities include MongoDB administration, Linux server tasks, and participation in architecture decisions. Strong Java expertise and familiarity with Python are essential for success.

Qualifications

• Bachelor's or higher in a relevant field; military substitute possible.
• 12+ years with a Bachelor’s, or 10+ with a Master’s in listed domains.
• Experience in C/C++/Java and Unix/Linux environments.
• Strong Java expertise with Python familiarity; Linux/MongoDB admin skills.

Responsibilities

• Design, develop, and maintain backend libraries and services.
• Implement data ingestion, transformation, and standardization logic.
• Develop Java-based solutions; Python support as needed.
• Create shared libraries for common data formats.
• Administer MongoDB and perform Linux system tasks.
• Collaborate via Git workflows and code reviews.

Skills

Java

Python

Linux

MongoDB

Backend development

Data transformation

REST APIs

Software architecture

Education

Bachelor's degree in EE/CS/CE/Math

Master's degree in CS/CE

Tools

Git

RPM

Unix/Linux

Job description

Title: Expert Applications Developer
Location: Hanover, MD
Compensation Range: $235 -$255K

Clearance: Active TS/SCI needed to apply

Company Overview

Cornerstone Defense is the Employer of Choice within the Intelligence, Defense, and Space communities of the U.S. Government. Realizing early on that our most prized assets are our employees, we continually focus our attention on improving the overall work/life experience they have supporting the mission. Our Team is pushed every day to use their industry leading knowledge to provide end-to-end solutions to combat our nation’s toughest and most secure problems. If you are looking for a place to not only be professionally challenged, but encouraged and supported by a company that cares, don’t look any further than Cornerstone Defense.

Benefits Overview

Cornerstone Defense offers a very comprehensive benefits package including, but not limited to:

• Medical, Dental and Vision Plans
• Generous PTO Policy
• 401(k)
• HSA and FSA options
• Life and Disability Insurance
• Tuition Reimbursement and Training
• Perks at Work Discount Program
• Referral Program
• Leads Generation Program
• CollegeAmerica 529
• Fitness Reimbursement Program
• Travel Assistance
• Norton Lifelock Benefit Solutions
• Life Planning Financial & Legal Services

Position Description

The Expert Application Developer designs, develops, and maintains backend libraries and integration services that convert diverse data formats into a standardized internal schema used across multiple applications. This is a hands‑on backend role focused primarily on Java, with occasional Python support. No UI development is involved.

The role also includes system administration duties, including managing MongoDB, working within Linux environments, performing server upgrades, installing RPMs, monitoring services, and troubleshooting operational issues.

Key responsibilities include implementing data ingestion and transformation logic, building reusable libraries for common data formats, ensuring performance and scalability, and contributing to architectural decisions. Collaboration is done through Git‑based workflows, code reviews, and continuous development improvements. The ideal candidate has strong Java expertise, familiarity with Python, experience with varied data formats, and practical Linux/MongoDB administration experience.

Core Tasks

• Design, develop, and maintain backend libraries and services for data ingestion, transformation, and standardization.
• Implement reusable schemas consumed by multiple organizational applications.
• Develop Java-based solutions, with supplemental Python work when needed.
• Create shared libraries supporting common data formats.
• Ensure backend system performance, scalability, and reliability.
• Contribute to architectural decisions related to data modeling and integration patterns.
• Administer and optimize MongoDB services.
• Perform Linux-based system administration tasks, including server upgrades and RPM installations.
• Monitor operational services and troubleshoot environment issues.
• Collaborate via Git source control, code reviews, and iterative workflow improvements.
• Analyze varied and evolving data formats (JSON, XML, CSV, custom).
• Provide problem-solving and technical insight across both development and operational domains.

Qualifications

Education:

• Bachelor’s degree in Electrical Engineering, Computer Science, Computer Engineering, or Mathematics (a minimum of four years of equivalent military experience may substitute for the degree).
• Master’s degree in Computer Science or Computer Engineering.

or

Experience Requirements:

• 12+ years with a Bachelor’s degree, or 10+ years with a Master’s degree, including knowledge/experience in three or more of the following:
• System Requirements Analysis
• Software System Design
• Software System Development
• Software System Integration
• Software System Testing

8+ years of experience in four or more of the following:

• Developing software applications in C, C++, or Java
• Developing software for Unix, Linux, or Windows environments
• Developing DLLs for Windows
• Development on computer telephony platforms using Dialogic or similar technologies
• Object-oriented programming
• Knowledge of common protocols/standards (TCP/IP, SNMP, H.323, X.25, 802.11, 802.16, SIP, MEGACO, MGCP)
• Web development with XML, PHP, MySQL, ColdFusion, or Apache
• Scripting with Perl, Python, Bourne shell, C shell, or proprietary languages
• Database experience with Sybase, Oracle, or Microsoft
• Reverse engineering and software analysis
• Kernel-level knowledge of Unix (Linux)
• Bit-level data analysis