Top Senior C# Jobs in Washington, DC

Design, build, test, and maintain tax-focused software solutions using Java, Python, C# and JavaScript. Apply ATDD and CI/CD, create APIs and microservices, perform code reviews and debugging, manage project delivery, and collaborate with cross-functional teams to improve business processes and client outcomes.

Develop and integrate custom-coded network monitoring and management tools using APIs, dashboards, databases, and enterprise technologies. Design, configure, test, document, and deploy solutions supporting global Cisco and Microsoft network environments. Collaborate with network engineers, DBAs, technical SMEs, customers, and contractor management while evaluating existing systems and recommending solutions. The role requires customer interaction, independent work in a small team, and support of Department of State network operations on secured hardware.

Develop and maintain C#/.NET applications throughout the software development lifecycle, including requirements analysis, architecture, coding, testing, debugging, integration, and configuration. Collaborate with clients and team members to prioritize development backlogs and plan releases. Build reliable, reusable code, analyze system requirements, and support applications using .NET technologies, SQL, APIs, JavaScript, and related systems.

Design, build, and lead development of scalable, secure, high-performance cloud ingestion systems handling large throughput uploads. Provide technical leadership, system design, architecture reviews, mentorship, cross-team collaboration, roadmap management, and process improvements across multi-cloud infrastructure.

Designs and implements advanced modeling and simulation tools to evaluate system performance and support strategic decision-making for national defense. The role involves quantitative analysis, agent-based and physics-based modeling, AI/ML optimization, reinforcement learning, EO-IR and 3D simulation, and collaboration with government clients. Preferred experience includes high-performance computing, computer vision, parallel programming, autonomous systems, and Linux or Unix environments.

Develop Temporal workflows and Go services to automate cloud operations, build reliable SRE platforms, participate in on-call/incident response, debug distributed systems, and enable self-service through documentation and CI/CD automation.

Design, build, test, and operate secure, scalable production software and services. Partner with customers and stakeholders to translate needs into technical solutions, lead technical workstreams, and apply engineering best practices including automated testing, CI/CD, observability, and documentation. Develop reusable components and AI- or LLM-based solutions while driving end-to-end delivery and continuous improvement.

Develops, tests, maintains, and troubleshoots enterprise and government Java applications. Designs APIs, supports architecture and documentation, integrates Java and .NET technologies, and contributes to CI/CD automation. Collaborates with analysts, QA, administrators, and stakeholders while ensuring application security, performance, reliability, and compliance with government standards. Requires Java, Spring, database, API, and Microsoft technology experience in a structured, compliance-driven environment.

Designs, develops, tests, deploys, and enhances Microsoft Power Platform applications and automated solutions. Translates user stories into secure, maintainable technical implementations using Power Apps, Power Automate, databases, web technologies, APIs, and low-code platforms. Responsibilities include agile collaboration, unit testing, troubleshooting, performance validation, documentation, training, knowledge transfer, and application security.

Develop and operate secure, scalable full-stack web applications and AI-powered agents using Microsoft technologies. Responsibilities include backend and frontend development, API and identity integrations, responsible AI implementation, testing, architecture reviews, deployment, observability, live-site support, and cross-team collaboration. The role also involves mentoring engineers, managing dependencies, and contributing reusable engineering practices and assets.

Designs and delivers cloud-based software solutions with strategic customers and Microsoft product teams. Leads requirements definition, architecture, dependency identification, design documentation, and development of maintainable code. Mentors engineers, contributes to open-source assets, coordinates project and release plans, and serves as a designated responsible individual for system reliability, monitoring, on-call support, performance, and operational improvements.

Develop and maintain Microsoft 365 solutions, including SharePoint architectures, Power Automate workflows, Power Apps interfaces, Power BI reporting, and data structures. Troubleshoot workflow, permissions, data, Excel, Access, and VBA issues; support data governance, migrations, testing, version control, and AI-connected workflows. Serve as a technical subject-matter expert, document solutions, gather requirements, and communicate technical decisions to business partners.

Design and implement runtime protocols, formats, and systems to capture, serialize, stream, and replay interactive 3D content across engines. Own C++ runtime and C# APIs across editor, build, simulation, streaming, and playback. Optimize for low-latency, determinism, memory and bandwidth constraints, and build AI interfaces for inspecting and invoking engine state.

Develop, test, deploy, maintain, and support enterprise software applications for a government customer. Responsibilities include designing application architectures, building front-end, business logic, REST API, and database components, creating Power BI reports, automating testing with Selenium, troubleshooting production issues, and assisting with deployments, configuration, upgrades, and documentation in an Agile Kanban environment.

Develops and implements full-stack software solutions from concept through production using agile methods. Designs, modifies, and enhances applications; writes front-end and back-end code; solves complex technical and workflow problems; evaluates architecture and operating environments; collaborates with cross-functional teams; and identifies system improvements. The role requires DHS suitability and participation in a government investigation and skills assessment.

Design, build, and support scalable full-stack software, backend services, databases, and cloud-native applications for investment risk and portfolio analytics. Contribute to architecture, technical decisions, automated testing, observability, CI/CD, data reliability, and technical debt reduction. Partner with engineering, product, business stakeholders, risk analysts, portfolio managers, and quants to deliver effective technology solutions.

Lead design and implementation of modernized insurance underwriting and policy administration solutions. Drive cloud transformation, data-driven and secure architectures, improve risk selection and claims resolution, enhance customer experience through automation, mentor technical teams, manage client relationships, and oversee project lifecycle, budgets, and delivery quality.

Designs, integrates, deploys, and troubleshoots autonomy and vehicle-intelligence systems across embedded hardware and software platforms. Responsibilities include integrating sensors, autopilots, datalinks, PNT/GPS/INS, and ground control stations; supporting UAV flight tests; conducting SIL and HIL validation; collaborating with vendors and defense customers; and delivering customer demonstrations. The role requires strong C++ development, robotics integration, networking, embedded Linux, and eligibility for a U.S. security clearance.

Build and evolve Unity’s PolySpatial core technology across low-level C++ and high-level C# systems. Design high-performance APIs for embedded, cross-process, and networked environments; manage execution timing and resource contention; and synchronize assets and components under bandwidth and latency constraints. Responsibilities include engine architecture, serialization, runtime performance, multithreading, networking, and end-to-end implementation and debugging.

Own Ditto’s Rust SDK observability strategy and implementation across iOS, Android, desktop, and embedded platforms. Design telemetry, logging, tracing, support bundles, buffering, sampling, and export systems optimized for constrained devices and intermittent connectivity. Improve logging performance, maintain Rust SDK features, and support customers debugging production integrations. The role requires systems-level Rust, FFI, cross-platform SDK development, observability design, strong written communication, and customer empathy.

Leads Agile full-stack engineering teams through design, development, testing, deployment, and support. Guides architecture, code quality, mentoring, technical risk management, operational priorities, and cross-functional delivery. Develops secure enterprise applications using Java, Angular, .NET, AWS, Docker, EKS, databases, Kafka, and CI/CD tooling. Coordinates with federal stakeholders, vendors, cybersecurity, infrastructure, and identity teams while supporting change management, incident response, governance, and production troubleshooting.

Build and maintain scalable full-stack web applications using .NET, React, Next.js, and Azure. Responsibilities include feature delivery, API and microservices development, testing, code reviews, architecture, performance optimization, security, CI/CD support, cloud deployment, and production support. Senior engineers will mentor teammates and influence engineering standards, while early-career engineers receive mentorship and progressively greater ownership.

Develop and architect enterprise Power Platform solutions using Power Apps, Power Automate, Dataverse, and Power BI. Responsibilities include data modeling, integrations, PCF development, Azure connectivity, governance, ALM, DevOps deployment, security, troubleshooting, documentation, stakeholder workshops, and mentoring. The role also involves designing user interfaces, conducting usability research, and creating dashboards. Work is onsite at a government facility in Washington, D.C.

Leads hands-on development of full-stack applications using .NET, React, Next.js, and Azure. Owns architecture, coding, code reviews, testing, security, reliability, observability, production support, and cloud deployment. Integrates AI and GenAI capabilities such as LLM features, RAG, semantic search, and agentic workflows. Mentors engineers, establishes technical standards, collaborates with stakeholders, supports hiring, and helps deliver scalable, secure software.

Leads technical initiatives and designs, builds, operates, and improves scalable distributed systems. Collaborates across organizations, drives maintainability and performance, evaluates emerging technologies, delivers iterative releases, and mentors engineers. Requires polyglot full-stack development, strong SQL and distributed systems expertise, cloud experience, communication skills, and quarterly or as-needed travel. Preferred experience includes event-driven architectures, AI-assisted development, Kafka, APIs, containers, infrastructure as code, monitoring, CI/CD, and agile methodologies.