Top .NET Developer Jobs in Toronto

Design, develop, modernize, and maintain enterprise applications and secure RESTful APIs using C#, .NET, ASP.NET Core, and SQL Server. Collaborate across the application stack with React, Angular, or similar frameworks; improve legacy systems, performance, reliability, and security. Participate in technical design, code reviews, automated testing, CI/CD, Docker deployments, troubleshooting, and Agile delivery. Contribute to AI-assisted engineering practices, documentation, mentoring, and continuous improvement.

Develop and test web applications using C#, .NET, ASP.NET MVC, SQL Server, WCF, and related Microsoft technologies. Responsibilities include authoring code, creating automated test scripts, performing unit testing, developing deployment packages, and working in an Agile environment. The role also requires object-oriented development, Entity Framework, TFS, and experience with SQL Server Analysis Services or other business intelligence tools.

Develop software using C++, .NET, and Ogre; apply 2D and 3D graphics fundamentals, work with shader languages including Cg, HLSL, and GLSL, and create user interfaces.

Develop and optimize high-performance .NET Core/C# backend microservices within a large distributed system. Responsibilities include PostgreSQL optimization, service communication, observability, distributed tracing, CI/CD integration, deployment reliability, resilience patterns, performance profiling, architecture reviews, and production troubleshooting. The role collaborates with DevOps, QA, and frontend teams and may involve Kubernetes, service mesh, asynchronous messaging, event-driven architecture, and cloud infrastructure.

Develop and maintain life insurance calculation capabilities and full-stack applications using C#, .NET, F#, React, APIs, microservices, and Azure Kubernetes Service. Responsibilities include designing secure solutions, automated testing, CI/CD, production troubleshooting, code reviews, technical documentation, and collaboration with cross-functional Agile teams. The role also involves refactoring applications, supporting distributed architectures, and translating complex insurance business logic into reliable software.

Leads application development and systems analysis initiatives, designing, enhancing, coding, testing, debugging, and implementing software applications. Partners with management and technology teams to define system improvements, resolve complex technical and business problems, and ensure solutions align with enterprise architecture. Establishes development standards, assesses risk and compliance, and coaches mid-level developers and analysts while supporting successful project delivery.

Design, develop, test, and maintain scalable web applications using Angular, .NET, and SQL Server. Participate throughout the software development lifecycle, collaborate with developers, designers, and stakeholders, follow coding and security standards, and improve development processes. The role requires strong software development experience, RESTful API development, Git, Agile methodologies, analytical skills, and effective communication.

Develop and own front-end solutions for a trade processing application supporting security financing transactions. Responsibilities include migrating legacy interfaces to React and HTML5, integrating APIs, implementing automated testing, analyzing technical problems, recommending security measures, supporting deployment, and collaborating with business and technology stakeholders. The role also involves estimating work, ensuring compliance, defining development standards, mentoring junior staff, and serving as a technical subject matter expert.

Own ToolHound’s technical and product roadmap, architecture, code quality, security, data, performance, releases, and AI-native product development. Lead modernization of its mature .NET platform, ship production AI features safely in a multi-tenant environment, improve velocity and reliability, and mentor the engineering team. Partner with the GM, customers, operators, and business stakeholders to prioritize work, communicate clearly, and increase the platform’s enterprise value.

Designs and builds scalable .NET and C# backend services, Web APIs, Azure Functions, Service Bus integrations, and App Service deployments. Manages SQL Server and Azure SQL data performance, CI/CD automation, observability, security, testing, and production incident resolution. Collaborates with architecture, QA, and DevOps teams to deliver secure Azure solutions, reviews code, enforces standards, and mentors developers.

Develop and enhance enterprise-grade SaaS eCommerce and .NET web applications using C# and ASP.NET. Responsibilities include implementing scalable features, refactoring for performance and reliability, contributing to development processes and architecture documentation, conducting code reviews, mentoring developers, and tracking technology trends. The role requires expertise in .NET, JavaScript, SQL Server, Windows Server technologies, testing frameworks, performance profiling, and web application architecture.

Develop and maintain enterprise-grade C# and .NET web applications for a SaaS eCommerce platform. Responsibilities include implementing features, improving performance, scalability, security, and reliability, contributing to development processes and architecture documentation, conducting code reviews, and mentoring junior developers. The role requires extensive experience with ASP.NET, JavaScript, SQL Server, Windows Server technologies, testing frameworks, and performance profiling tools.

Develop and maintain full-stack .NET applications for the Securitization Technology team. Responsibilities include solution design, C# development, systems administration, testing, deployment support, incident management, performance improvements, security practices, monitoring, and troubleshooting. The role collaborates with business and technology stakeholders, contributes to project planning, provides technical leadership, and supports critical capital markets platforms in an Agile environment.

Leads the architecture, development, deployment, and support of enterprise full-stack applications using .NET, Angular, AWS, microservices, and AI-assisted development tools. Provides technical leadership, mentoring, and engineering standards while driving cloud modernization, CI/CD, DevOps, security, observability, performance, and production support. Collaborates with stakeholders and technology teams on solution design, technical roadmaps, Agile delivery, and enterprise-scale initiatives.

Develop and maintain full-stack software solutions using .NET and related web technologies. Responsibilities include feature development, unit testing, code reviews, incident support, troubleshooting, system documentation, application integration, quality assurance, and collaboration with technology and business stakeholders. The role also supports continuous improvement, automation, risk management, and mentoring while ensuring solutions meet architectural, performance, security, and regulatory standards.

Leads Aviva Canada's $165M+ high-net-worth insurance portfolio, overseeing strategy, profitable growth, underwriting performance, risk selection, pricing execution, customer propositions, broker partnerships, and operational excellence. The role manages transformation, cross-functional collaboration, regulatory and financial outcomes, and a high-performing underwriting team while balancing growth, profitability, client experience, and portfolio risk.

Develop and own front-end and full-stack web applications for Citi’s trade processing platform. Build React and HTML5 interfaces, modernize legacy UI components, integrate .NET/C# services, and ensure automated testing, security, compliance, and design quality. Responsibilities include requirements analysis, implementation, technical recommendations, production support, stakeholder consultation, risk assessment, process standards, and mentoring junior team members. The role supports capital markets applications and requires independent judgment and collaboration across technology and business teams.

Leads Greenfield Global’s enterprise Net Zero and carbon management strategy across North America. Responsibilities include developing carbon reduction roadmaps, tracking emissions and sustainability goals, guiding regulatory and carbon market compliance, conducting carbon and lifecycle impact assessments, forecasting and reporting performance, and partnering with manufacturing, operations, supply chain, finance, procurement, and commercial teams to identify decarbonization opportunities.

Build and improve 1Password’s SaaS Manager platform for discovering, governing, and optimizing enterprise SaaS and AI ecosystems. Own well-defined features end to end, write tested and documented code, participate in code reviews, collaborate with product and design, and proactively resolve blockers and improve engineering processes. The role involves .NET/C# development, document databases, AI-assisted development, and learning across multiple technical stacks.

Responsible for leading programming efforts, mentoring teammates, and developing robust, cloud-based applications using modern technologies and methodologies.

Develop and maintain warehouse management software using C#, ASP.NET, .NET Core, Web APIs, and SQL Server. Modernize legacy applications, build backend services, support mobile and Windows applications, and contribute to architecture, performance, CI/CD, code quality, and security improvements. Collaborate with product, operations, and engineering teams, troubleshoot complex issues, conduct code reviews, and support Agile development and process improvement initiatives.

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 the design, development, maintenance, and technical direction of a scalable insurance SaaS platform. Works across .NET back-end and Vue/React front-end technologies, optimizes performance, enforces coding and security standards, leads code reviews, resolves bugs, and mentors developers. Collaborates with product, design, and engineering teams on architecture, requirements, testing, cloud infrastructure, microservices, and continuous platform improvement.

Lead development of secure, scalable digital banking software across front-end and backend systems. Design Angular or React applications, build APIs, optimize SQL performance, integrate third-party platforms, improve code quality, implement testing strategies, and mentor engineers. Collaborate with cross-functional teams in an Agile environment while supporting cloud-native practices, regulatory compliance, and continuous product improvement.

Design, build, and own integrations between a fintech platform and ERP or accounting systems. Develop REST and SOAP services, synchronization and reconciliation workflows, data mappings, validation, retries, audit trails, and observability. Improve reliability and performance, troubleshoot production failures, and collaborate with onboarding, support, engineering, and non-technical stakeholders. The role requires strong C#, .NET, SQL Server, messaging, and financial-system integration experience, with opportunities to use Azure and AI-assisted development tools.