Top Senior C# Jobs in San Diego, CA

Lead design and rewrite of cloud-native core systems. Build scalable back-end services and front-end features, drive architecture and testing discussions, mentor engineers, and improve telemetry, performance, and reliability.

Lead refactoring and optimization of scalable data pipelines, design next-generation distributed storage and processing systems, build clean interfaces for diverse data consumers, mentor engineers, and establish engineering standards and processes.

Drive technical direction and architecture across teams for enterprise retail software. Improve platform reliability and performance, scope customer-facing features, mentor engineers, de-risk large work, and embed AI-native practices (LLMs/agents) into engineering workflows.

Build and maintain the full-stack Raise product: polished donor-facing UIs and backend systems. Own features end-to-end, ensure scalability, reliability, and performance, review AI-generated code, collaborate with Product and Design, write clean testable code, and support observability and incident resolution.

Design and implement backend APIs and performant database schemas (Postgres/SQL); build scalable, testable C# services; work in Agile cross-functional squads; incorporate AI-assisted development tools; and drive engineering maturity and efficiency.

Lead front-end-focused full‑stack development for a multi‑tenant SaaS online banking platform. Build reusable component libraries, migrate legacy UI, optimize UI performance, troubleshoot across front-end and service layers, participate in on‑call rotations, mentor junior engineers, and ensure API‑first integrations and cloud‑native deployments.

Lead design, implementation, and delivery of software via CI/CD; maintain and optimize applications; drive architecture, code reviews, testing, security, and PCI DSS compliance; mentor engineers and lead scrum team activities.

Lead, mentor, and grow a software engineering team to deliver high-quality, scalable microservice-based solutions. Manage Agile processes, collaborate with Product, enforce engineering best practices, and drive continuous improvement in architecture, quality, and team performance. Participate in hiring, backlog planning, and drive measurable improvements in engineering execution.

Design, develop, and maintain automated test frameworks for front-end and web services. Integrate tests into CI/CD, write unit/component/integration/functional/performance tests, debug front-end and API issues, collaborate with Agile teams, and improve test coverage, release velocity, and production health. Work uses Groovy/Geb and Java/HttpClient and may involve contact center integration.

Design, develop, deploy, and maintain backend components and large-scale cloud-based systems. Write tests, perform code reviews, debug, and collaborate with cross-functional teams to build scalable APIs, microservices, and reliable production software in an agile environment.

Lead Sitecore development for multilingual, multisite implementations using Helix and SXA. Architect and build components, templates, renderings, caching, and Sitecore APIs. Integrate via REST/web services, host and operate Sitecore on Azure (Search/Solr, Redis, App Services), manage CI/CD with Azure DevOps/Unicorn, enforce Gitflow branching, troubleshoot web issues, review implementations, and mentor/manage the team.

Lead API Developer to architect, build, and maintain scalable .NET/C# REST APIs on Azure. Enforce engineering best practices (CI/CD, code reviews, high test coverage), containerize with Docker/Kubernetes, integrate microservices with cloud databases/storage and IAM (OAuth/SAML/OIDC), use Azure DevOps, monitor analytics, and provide technical leadership and documentation (Swagger).

Design, develop, and maintain high-performance web applications and WebAPIs using .NET 6 and React. Build scalable, reliable services, optimize performance, troubleshoot defects, and collaborate with product and development teams. Use Azure platform services, NoSQL/SQL databases, CI/CD pipelines, and propose continuous improvements.

Lead architecture and development of scalable REST-based microservices using .NET 6+, ASP.NET and C#. Drive API design, documentation, CI/CD with Azure DevOps, Azure deployments, event-driven integrations, testing (xUnit/NUnit), and mentor engineers while ensuring performance, security (JWT/OAuth/SAML), and observability for large eCommerce systems.

Lead a team of .NET developers providing technical and architectural leadership across .NET-based applications. Drive design decisions, enforce coding standards, plan and estimate work, perform code reviews, mentor developers, troubleshoot complex issues, and collaborate with product and project teams to deliver scalable, secure microservices and APIs.

Join an early-stage platform team to scale and mature a mortgage origination platform. Work across the stack to improve distributed systems, performance, observability, and infrastructure tooling, and help define engineering standards and frameworks for growth.

Design, develop, and deliver scalable backend systems and components using .NET 10 and C#. Build and maintain databases and messaging infrastructure (PostgreSQL/SQL Server, RabbitMQ), deploy with Docker and AWS, apply DDD and ORMs, triage/prioritize work, and contribute to distributed, event-driven architecture with emphasis on reliability and idempotency.

Develop, configure, integrate, and operationalize command-and-control (C2) and Common Operating Picture (COP) applications. Build workflow automation, event management, alerting, data fusion, dashboards, and operator-focused UX. Support testing, interoperability validation, demonstrations, and operational readiness while collaborating with systems engineering and stakeholders.

Design and develop software for automated laboratory workflows, build data pipelines, implement machine learning models, and integrate various systems to enhance biotherapeutics discovery.

Lead design, development, and modernization of a proprietary Loan Management System. Build and refactor full-stack features, improve scalability, reliability, CI/CD, and observability, troubleshoot production issues, and collaborate with Product, QA, DevOps, and engineering teams while mentoring peers and driving engineering best practices.

Lead end-to-end design, development, and quality of enterprise cloud solutions. Estimate costs, define quality criteria, implement complex systems, manage engineering processes, risks, and dependencies, and mentor teams. Serve as technical lead across large, cross-functional projects to deliver measurable, user-centric healthcare technology solutions.

Build and maintain scalable backend microservices and developer-facing APIs, lead projects end-to-end, collaborate with product and engineering teams, design secure/versioned APIs, and manage cloud infrastructure using IaC.

Build and maintain the GG App across Windows, macOS, and iOS including installers, background services, auto-update systems, enterprise deployment paths, health reporting, AWS backend, and documentation. Lead architecture decisions, mentor engineers, participate in on-call support, and champion AI adoption and automation across engineering.

Lead design and delivery of cloud and AI production systems, partner with stakeholders to translate needs into architecture, ensure security and quality, mentor engineers, and drive customer adoption and scalable reusable solutions across engagements.

Design, build, and operate high-performance, distributed .NET and TypeScript/React applications and cloud APIs. Implement microservices on AWS, automated testing, GitHub Actions CI/CD, observability with OpenTelemetry, and diagnose production issues to ensure scalable, reliable systems.