Top .NET Developer Jobs in Philadelphia, PA

As a Software Engineer, you will design, develop, and deliver high-quality software, contribute to code reviews, monitor application performance, and ensure maintainability and consistency across products.

Design, build, and operate .NET backend services and APIs using C#/ASP.NET Core and EF Core/SQL. Author and iterate specification artifacts (OpenSpec), leverage AI coding assistants, implement automated tests, ship via CI/CD to the cloud, review peers' specs/code, mentor engineers, and collaborate with product, QA, and cross-functional teams to deliver production services.

The role involves converting visual designs into web pages, collaborating with teams, and ensuring compliance with best practices for front-end development.

Lead and mentor an engineering team building GovIntel and GovChannel product capabilities. Own technical direction, design and deliver scalable SaaS features, APIs, integrations, and platform reliability. Partner with Product, QA, Cloud Ops, and stakeholders to prioritize work, drive CI/CD and observability practices, lead reviews and incident response, and apply AI-assisted tools to improve development speed and quality.

As a Senior Software Engineer at PerfectServe, you'll design, build, and maintain high-quality code for healthcare communication systems, mentoring junior engineers and collaborating across teams to improve patient care and clinical workflows.

Lead backend development on the scheduling platform modernization, contribute across products, write APIs, and drive AI-accelerated software development workflows.

Lead backend development on the scheduling platform modernization. Contribute across Python and .NET ecosystems, write APIs, review code, and support AI-accelerated development workflows while collaborating in a remote team environment.

The Senior .NET Software Engineer will drive development of .NET software products, focusing on back-end engineering, code reviews, and collaborating with cross-functional teams.

The Staff Software Engineer will design .NET infrastructure, automate builds, maintain tooling for .NET libraries, and mentor peers while ensuring security and reliability.

The C#/.NET Developer will design, develop, and implement software solutions, collaborating in an Agile environment, and ensuring code quality and performance.

Expert-level full‑stack .NET engineer who designs, develops, tests, and supports secure, scalable enterprise applications. Leads large projects, authors technical specs, mentors engineers, enforces SDLC and security/audit requirements, participates in Agile/Scrum, and drives technical strategy and innovation. Availability for occasional travel and on-call support is required.

The role involves full-stack software development, adhering to Agile practices, and collaborating across teams. Responsibilities include coding, testing, and maintaining software systems while mentoring team members.

Design, develop, test, and maintain scalable .NET web applications. Contribute to architecture and technical design, produce database objects, perform code reviews, mentor junior engineers, support production, and collaborate with cross-functional teams in Agile delivery.

Design, develop, and maintain scalable .NET-based applications. Contribute to solution architecture, write and unit test code, perform code reviews, mentor junior engineers, develop database objects, support production, and collaborate with product, data, and client teams in an Agile environment.

Develop and maintain enhancements for the M5 FleetFocus web application using C#, ASPX/ASP.NET, HTML5, XML, and JavaScript. Build and modify SQL statements and database objects in Oracle and SQL Server. Define C# interfaces for 3rd-party integrations, troubleshoot tickets, collaborate with PM/QA/support, and use Visual Studio 2013 and SVN for code changes.

Develop and maintain scalable software solutions, mentor developers, and integrate AI tools. Collaborate on technical solutions aligned with business goals.

The Full Stack .NET Developer will enhance Coretek's Insights product by developing features, improving user experience, and collaborating with stakeholders while applying Agile methodologies and CI/CD practices.

The Senior .NET Software Engineer will develop and manage work-management software using a wide technology stack while collaborating with a remote engineering team.

Design, build, test, and maintain .NET applications using C# and Entity Framework Core for client/server and Azure web environments. Participate in code reviews, document development methods, apply Agile practices, use Azure DevOps for source control, develop UI components (HTML/CSS/jQuery/Bootstrap), and incorporate security best practices throughout the SDLC.

Design, develop, and maintain scalable ASP.NET/C# APIs and microservices and front-end interfaces (Vue.js, AngularJS) for retail omni-channel and POS platforms. Contribute to architecture, write production-quality code, troubleshoot issues, participate in code reviews, and collaborate with product, design, and QA to deliver features with minimal onboarding.

Design, develop, implement and support web applications using .NET Core. Collaborate with internal bank teams and external vendors, troubleshoot production issues, and apply strong interpersonal, leadership, and problem-solving skills.

Seeking a Senior Full Stack .NET Developer to work on a social good project, with strong skills in C#, AngularJS, design, and UX. Requires 5+ years of experience.

The Staff Engineer will leverage 5+ years of experience in C#, JavaScript, and frameworks to lead and innovate solutions in a collaborative environment.

Own production reliability for customer-facing radar and weather data services across Azure, colocation, and edge Kubernetes. Refactor C#/.NET services for multi-replica safety, design multi-cluster HA, operate self-managed Kubernetes, improve observability and automation, lead incident response and postmortems, and drive operational excellence and capacity planning.

As a Principal .NET Software Engineer at Versapay, you will modernize payments infrastructure, improve scalability, design distributed services, and take ownership of payment workflows while collaborating with various teams to enhance customer experience.