Senior Software Engineer

.NET • API Development

About the Role

The Senior Software Engineer leads implementation for significant projects or major components, mentors junior engineers, and solves complex problems with high autonomy while collaborating cross-functionally. This position is part of a cross-functional software engineering team comprised of software engineers and QA automation engineers, and reports to an Engineering Team Lead.

In this role, you will focus on building scalable, maintainable backend systems and APIs using the .NET ecosystem, playing a key part in shaping architecture decisions and driving engineering excellence.

Key Responsibilities

• Lead implementation for large features or multi-sprint projects, driving backend execution and delivery using C# and the .NET platform.

• Design, build, and maintain RESTful and/or GraphQL APIs that are performant, secure, and well-documented.

• Decompose complex problems into milestones; translate acceptance criteria into robust, testable backend solutions.

• Mentor engineers through code reviews, pairing, and technical guidance; elevate team capabilities.

• Influence engineering practices (testing, design hygiene, operational readiness) to raise overall quality.

• Contribute to proofs-of-concept and prototypes to validate architectural approaches and reduce delivery risk.

• Collaborate effectively with stakeholders (product, QA, leads) throughout development and testing.

• Other duties as assigned.

Qualifications

Required

• Bachelor’s degree or equivalent practical experience.

• 6+ years of professional software engineering experience.

• Deep proficiency in C# and the .NET ecosystem (.NET 6+, ASP.NET Core).

• Proven experience designing and building RESTful APIs, including versioning, authentication, and documentation (e.g., Swagger/OpenAPI).

• Strong fundamentals in software design, debugging, and maintainable coding practices.

• Expertise working with relational data stores (e.g., SQL Server, PostgreSQL) and ORM frameworks (e.g., Entity Framework Core).

• Experience with cloud platforms, e.g. Azure or AWS, including deploying and operating .NET services.

• Demonstrated ability to lead technical delivery, mentor others, and handle ambiguity effectively.

• Track record of raising engineering quality (reliability, performance, testing, maintainability).

• Experience participating in estimation and sprint planning.

• Proficiency with version control systems (Git) and defect-tracking tools (e.g., Jira).

• Strong written and verbal communication skills.

• Detail-oriented, with strong analytical and problem-solving skills.

• Demonstrated growth mindset — self-driven learning and continuous improvement.

• Ability to work in a fast-paced, dynamic environment and balance multiple priorities.

Nice to Have

• Experience using AI tools (e.g., GitHub Copilot, Claude) to accelerate software development.

• Familiarity with message brokers or event-driven architectures (e.g., Azure Service Bus, RabbitMQ, Kafka).

• Experience with microservices architecture and containerization (Docker, Kubernetes).

• Knowledge of gRPC or GraphQL API patterns.

• Background in API gateway configuration and management (e.g., Azure API Management, AWS API Gateway).

• Exposure to CI/CD pipelines and DevOps practices.

What Success Looks Like

• Delivers major backend initiatives with predictable execution and clear stakeholder communication.

• Builds APIs and services that are reliable, secure, and easy for other teams to consume.

• Raises team performance through mentorship and improved engineering practices.

• Resolves complex technical challenges efficiently and leaves systems healthier than before.

WORKING CONDITIONS:

• · Normal office environment

• · Extending viewing of computer screens

ESSENTIAL FUNCTIONS:

• Spends time at a computer workstation and desk.

• Moves throughout department or other locations to access or exchange information.

• May involve carrying loads up to 50 lbs. and being able to remain in a stationary position.

• May involve lowering oneself to file, and reaching, twisting or turning.

• Involves handling office materials, typing, writing and other tasks that require manual dexterity.

• Continuous listening.

• Ability to communicate information.

• This job may require accommodating different bodily movements and physical abilities.

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