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Senior C#/.NET Developer

Cognizant’s Digital Engineering practice is seeking a highly qualified a Senior C#/.NET Developer with at least 6 + years experience developing and building high-performing, scalable, enterprise applications. You will be part of a digital software team that works on high-demand applications. Our engineers have a passion for high-quality, reliable, and maintainable code. You will work side by side with product managers, designers, and clients, making decisions together to quickly deliver valuable working software to clients and their users. Our engineers are agile and retrospective, and not afraid to identify what we’re doing wrong, so we can fix it, and what we’re doing right, so we can improve on it. Above all, we judge success by the success of our team and the happiness of our customers.

Cognizant Digital Engineering If you’re like us, you’ve got big ideas. At Cognizant, we’re exploring new ideas every day. We help industry leading companies reinvent their business models and innovate products that create new value—by connecting people with things, insights, and experiences. Cognizant digital engineering designs, engineers and deliver digital products and experiences that drive digital-first business models. We offer the most comprehensive digital engineering expertise and client-centric methodology for sustainable innovation.

Location: Toronto, ON, CANADA (Onsite)

You must be legally authorized to work in Canada without the need for employer sponsorship, now or at any time in the future.

Roles & Responsibilities:

· Design, develop, and maintain server-side components using C# and .NET (Core/Framework) following clean architecture and SOLID principles.

· Build and maintain RESTful APIs (design, versioning, pagination, error handling, and documentation) and ensure secure authentication/authorization.

· Develop middleware and integration components to connect internal services with external systems (message formats, adapters, routing, transformation, and orchestration).

· Implement and consume integrations using common patterns (sync/async), ensuring resiliency (timeouts, retries, circuit breakers) and observability (logging, tracing, metrics).

· Write unit/integration tests and support automated CI/CD pipelines; ensure code quality through reviews and static analysis.

· Troubleshoot production issues, perform root-cause analysis, and deliver performance/reliability improvements.

· Collaborate with product owners, architects, and QA to refine requirements, estimate work, and deliver features within sprint timelines.

· Produce and maintain technical documentation for APIs, integrations, configuration, and runbooks.

Required Qualifications:

Must-Have Skills:

· Strong experience in C# and .NET development

· Proven expertise in server-side development

· Hands-on experience with RESTful APIs

· Experience in middleware integration

· Solid understanding of Design Patterns, SOLID principles, and Object-Oriented Programming (OOP)

· Ability to write clean, efficient, and maintainable code

Nice-to-Have Skills:

· Experience with relational databases

· Familiarity with MongoDB

· Knowledge of Redis

Canadian Pay Transparency Statement

We regularly assess market data to ensure we offer a competitive compensation package for our associates. The base salary for this position ranges between $ 61,650 – 96,500 per year. Where the successful candidate may fall within the range depends on relevant education, work and/or management experience and other business-related and job-necessary qualifications. This position is also eligible for Cognizant’s discretionary annual performance-based bonus, as well as benefits that support your physical, mental and financial wellbeing.

Why Choose Cognizant?

It takes a lot to succeed in today’s fast-paced market, and Cognizant Technology Solutions has become a leader in the industry. We love big ideas and even bigger dreams! We stand out because we put human experiences at the core. Our associates enjoy robust benefits and training opportunities from our industry-recognized, award-winning Academy team. You will have access to hundreds of technical training courses to keep your skillsets fresh and have opportunities to acquire certifications on the newest technologies.

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Cognizant is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to sex, gender identity, sexual orientation, race, color, religion, national origin, disability, protected Veteran status, age, or any other characteristic protected by law.