Top Senior C# Jobs in San Diego, CA

Build and lead a scalable platform engineering function spanning CI/CD, infrastructure, observability, developer tooling, environments, and production operations. Develop internal tools, reusable automation, paved roads, and AI-assisted workflows that improve developer experience, delivery reliability, and engineering productivity. Partner across teams, guide architecture and standards, measure DORA and DX metrics, and shape the platform roadmap while providing hands-on technical leadership.

Lead the architecture and technical direction of Alpaca’s Trading API customer experience. Own identity, authentication, authorization, account models, partner access, and customer-facing trading applications. Drive backend modernization, real-time trading features, security practices, safe production delivery, observability, incident prevention, design reviews, and engineering mentorship. Collaborate with Product, Design, Compliance, Security, Brokerage Operations, and platform teams while remaining a hands-on principal contributor.

Design, test, document, and deploy geospatial software solutions for defense and intelligence imagery. Integrate analytical toolkits with ArcGIS, define user requirements, lead lab testing and automated QA efforts, and collaborate on software releases. The role applies remote sensing, photogrammetry, image processing, and AI while mentoring colleagues and managing project dependencies.

Develop and maintain software using C#, .NET, web technologies, SQL Server, and AWS. Participate in the full SDLC and Agile Scrum processes, including design, development, unit testing, defect resolution, backlog refinement, and collaboration with product and QA teams. Build solutions using Microsoft-stack technologies, optimize databases and stored procedures, and support cloud-based application delivery.

Designs, develops, deploys, and sustains Azure infrastructure for AI training and inference workloads. Responsibilities include coding, hardware and software integration, distributed systems, networking, GPU and cluster design, performance optimization, debugging, automation, test-driven engineering, documentation, partner collaboration, and on-call incident response. The role drives scalable, reliable infrastructure and mentors engineers while improving quality, maintainability, and customer outcomes.

Develops and supports secure full-stack applications and integrations across Microsoft Dynamics 365, Business Central, Power Platform, and Azure. Responsibilities include building C#/.NET APIs and services, creating React-based web experiences, implementing authentication and cloud security, troubleshooting production systems, and managing CI/CD through GitHub or Azure DevOps. The role partners with technical and business stakeholders to translate requirements into maintainable solutions, resolve defects, and improve platform reliability.

Leads hands-on Appian application development across design, coding, testing, deployment, maintenance, production support, and incident triage. Serves as the senior developer on an Agile team, coordinating with product owners, business analysts, UX, and QA. Produces architecture and technical documentation, guides integrations and security modeling, oversees development tasks, performs peer reviews, and supports compliance, risk management, and continuous Appian platform improvement.

Designs and builds highly scalable, fault-tolerant Azure compute services, microservices, REST APIs, billing pipelines, and distributed systems. Responsibilities include improving availability, security, scalability, performance, disaster recovery, and compute utilization; using telemetry and data-driven insights; developing cloud-native solutions with containers, NoSQL, and Big Data technologies; and leveraging AI-assisted development in an Agile environment.

Design and lead development of high-performance networking infrastructure for large-scale AI training and inference in Azure. Architect low-latency, low-jitter communication frameworks, optimize distributed systems, benchmark scalability, resolve complex networking issues, and improve reliability, observability, and performance. Mentor engineers, create technical designs, manage dependencies, and participate in on-call operations for critical services.

Build and own scalable full-stack cloud-native services and web frontends on AWS for healthcare imaging workflows. Shape architecture and technical direction, implement automated testing, CI/CD, observability, and security, and ensure compliance with HL7, DICOM, and regulatory requirements. Collaborate with Product, UX, and Clinical teams while mentoring developers and supporting reliable production software.

Leads architecture and development of Azure Storage table, metadata, and indexing systems at massive cloud scale. Designs distributed-system primitives for partitioning, indexing, transactions, consistency, replication, caching, and high-performance data access. Drives architectural decisions, prototypes innovations through production, and improves performance, scalability, reliability, and cost efficiency. Requires deep expertise in distributed storage, databases, or large-scale systems.

Develop custom applications, integrations, and system updates for Jenzabar customers using C#, .NET, XML, SQL, REST APIs, and Boomi. Responsibilities include requirements gathering, solution design, troubleshooting, programming, customer consulting, statements of work, training, collaboration, and mentoring application programmers.

Leads QA automation initiatives by developing and maintaining automated functional, regression, API, and integration test suites for Guidewire software and mobile applications. Improves CI/CD pipelines, performs root cause analysis, drives quality improvements, collaborates with developers and product owners, and mentors junior QA engineers.

Build and maintain scalable, cloud-native APIs and high-value core system components using .NET and related technologies. Lead software architecture and testing discussions, enhance core offerings, collaborate cross-functionally, and ensure quality through code reviews, unit testing, functional testing, telemetry, and performance tuning. Mentor teammates and contribute to continuous technical and process improvement.

Leads California mechanical facilities business development while delivering senior-level engineering services. Designs HVAC, plumbing, hydronic, central plant, ventilation, and related building systems using Revit; coordinates multidisciplinary teams; performs site assessments, quality reviews, construction administration, commissioning support, and client presentations. Develops proposals, budgets, schedules, and market intelligence, builds client relationships, supports pursuits, and mentors junior engineers.

Develop and support a cloud-native workload credentials management solution within a SaaS platform. Responsibilities include designing scalable full-stack services, orchestration, APIs, distributed systems, and microservices; providing technical leadership; leading projects through delivery; collaborating cross-functionally; mentoring engineers; and applying engineering best practices. The role requires extensive Go development, cloud and SaaS expertise, modern JavaScript frameworks, and experience operating enterprise systems at scale.

Leads complex SaaS and digital banking implementations, including configuration, customization, validation, troubleshooting, third-party integrations, and post-go-live stabilization. Serves as the primary technical resource for client engagements, coordinates with project managers, engineers, vendors, and customers, and translates technical issues into actionable solutions. Develops implementation documentation, improves processes, mentors junior engineers, manages concurrent priorities, and communicates platform enhancement opportunities to product and engineering teams.

Owns production reliability for a B2B SaaS platform, including SLOs, error budgets, observability, alerting, incident response, recovery exercises, performance and capacity engineering, load testing, disaster recovery, and production readiness. The role writes automation and production code, leads incidents, coaches engineering teams, and improves reliability across Kubernetes, Azure, databases, messaging, and service infrastructure.

Design, build, and maintain scalable applications, APIs, mobile platforms, booking systems, clinical integrations, and healthcare data systems. Own features end to end, make architectural decisions, improve security and reliability, and contribute to cloud deployment, CI/CD, monitoring, and DevOps. Collaborate with clinical, operations, and patient experience teams to deliver secure digital tools that improve patient care and clinic efficiency.

Build full-stack software, backend services, APIs, frontend experiences, and shared integration capabilities supporting AI initiatives across Keeper’s products. Integrate LLMs, agents, and tool-calling workflows into secure production environments while maintaining zero-knowledge principles. Troubleshoot cross-product systems, improve reliability and observability, contribute to architecture and code reviews, automate testing and CI/CD, and collaborate with AI, product, and engineering teams.

Build and maintain secure, scalable backend systems for Mindbody products. Design microservices, write tested and maintainable code, monitor applications, participate in reviews, and collaborate with Product, Design, QA, and Engineering teams. The description also includes leadership responsibilities such as managing backend development teams, coaching managers and engineers, establishing delivery processes, and driving technical and organizational improvement.

Develop and maintain mission-critical full-stack web and database applications, ETL pipelines, reporting solutions, and system integrations. Responsibilities include writing and testing code, creating advanced T-SQL and SSRS solutions, improving existing programs, documenting data lineage, troubleshooting applications and databases, and collaborating with business and technical teams in an Agile environment.

Develop cross-platform C++ and Qt software for network device discovery, monitoring, and data collection across Windows and Linux. Build high-performance, concurrent, asynchronous systems that communicate with thousands of devices using SNMP, SSH, ICMP, WMI, and related protocols. Own testing, troubleshoot issues across application, operating-system, and network layers, optimize reliability and performance, and collaborate with backend, UI, QA, and product teams.

Leads photonic integrated circuit test software architecture, infrastructure improvements, test-station automation, and hardware-control software development. Oversees software migration across LabVIEW, Python, MATLAB, C#, and C++, while leading a small software team and mentoring engineers. The role supports electrical and optical testing of InP-based transceiver PICs at wafer, die, and subassembly levels, including vision systems, probe positioning, calibration, and test software revision control.

Design, develop, secure, and maintain mission-critical Microsoft-platform software for DoD programs. Build C# and .NET applications, responsive JavaScript and EXT JS interfaces, REST APIs, and optimized SQL Server databases. Apply secure coding, STIG, RMF, threat modeling, vulnerability remediation, documentation, and compliance practices. Integrate Kiro AI capabilities, collaborate with cybersecurity and engineering teams, and support deployment and sustainment in classified or controlled environments.