Software Developer (Automation & Distributed Integration Systems)

Dobbs Defense Solutions, LLC•Ashburn, VA

2d•$114,700 - $117,475•Hybrid

About The Position

Dobbs Defense Solutions is seeking an experienced Software Development Engineer in Test (SDET) to design and implement automated test solutions for a distributed integration service that supports license plate capture from video streams, RFID card reads, and entry/exit sensor simulation. This role will focus on validating a .NET Core-based integration service that uses TCP and HTTP listeners to receive data from hardware components and exchange requests with downstream services. The ideal candidate will build an automation framework capable of simulating hardware inputs, validating message flows, testing service interactions, and ensuring reliability, accuracy, and performance across end-to-end workflows.

Requirements

Bachelor’s degree in Computer Science, Software Engineering, Electrical Engineering, or related field, or equivalent practical experience
5+ years of experience in software testing and test automation, with strong hands-on SDET experience
Strong programming experience in C# and .NET / .NET Core
Experience building automation frameworks for backend services, APIs, and distributed systems
Experience testing HTTP APIs and TCP socket-based interfaces
Experience developing mock services, simulators, or test harnesses for external systems or hardware interfaces
Strong understanding of integration testing, system testing, regression testing, and end-to-end automation
Experience validating asynchronous and event-driven workflows
Familiarity with log analysis, troubleshooting distributed systems, and root cause investigation
Experience using test tools and frameworks such as xUnit, NUnit, MSTest, Postman/Newman, RestAssured-like API tools, or custom test harnesses
Experience with source control and DevOps tools such as Git, Azure DevOps, GitLab, or Jenkins
Strong analytical and problem-solving skills with attention to detail

Nice To Haves

Experience testing systems that integrate with physical hardware devices, sensors, cameras, RFID readers, or other field equipment
Experience with video-based testing or validating image/video processing workflows
Experience with message-oriented or distributed architectures, including queues, brokers, or service-to-service communication patterns
Familiarity with network protocols, socket communication, and troubleshooting connectivity issues
Experience with performance, load, or soak testing for integration services
Experience working from ICDs, interface specifications, sequence diagrams, and system requirements
Familiarity with containerized environments and service deployment patterns
Experience in regulated, operational, or mission-critical environments
Languages/Frameworks: C#, .NET Core, scripting in PowerShell or Python preferred
Interfaces/Protocols: HTTP/REST, TCP/IP, sockets
Testing: API automation, integration testing, system testing, regression testing, negative testing, fault injection
Tools: xUnit/NUnit/MSTest, Git, CI/CD pipelines, log analysis and monitoring tools
Nice to Have: Docker, mock servers, network packet analysis tools, test data generation tools

Responsibilities

Design, develop, and maintain automated test frameworks for a distributed integration system built on .NET Core
Create automated test solutions to validate: License plate capture and processing from video streams RFID card read events Entry and exit sensor trigger simulation End-to-end message flow between hardware-facing listeners and downstream services
Develop test harnesses, simulators, and mock services to emulate hardware devices and external service dependencies
Build automated tests for TCP and HTTP listener interfaces, including positive, negative, edge case, and fault-injection scenarios
Validate data ingestion, parsing, routing, transformation, and handoff across multiple services in a distributed environment
Automate integration, system, regression, and interface testing
Develop test scenarios for sequencing and timing-sensitive events, such as vehicle entry, sensor trigger order, RFID reads, and plate capture correlation
Verify system behavior under abnormal conditions such as delayed messages, malformed payloads, dropped connections, duplicate events, and out-of-order events
Create automated validation for logs, service responses, queues/messages, and database or persisted outputs where applicable
Partner with software engineers, architects, and integration teams to understand interface control documents, service behavior, and operational workflows
Support CI/CD integration so automated tests can run in build and deployment pipelines
Produce clear test documentation including test plans, test cases, traceability, defect reports, and automation run results
Help define test data strategy for video clips, RFID event payloads, and simulated sensor event sequences
Contribute to performance and reliability testing for distributed service communication and event processing