• Sr. .NET Developer

    TEKsystems (Lansing, MI)


    We are looking for a Senior .NET Developer to join a high-impact modernization initiative focused on rewriting an accounts receivable system. This role involves full-stack development using .NET Core and C#, building secure and scalable web applications, and collaborating in an Agile environment. You will work on RESTful APIs, document upload functionality, and ensure best practices in coding and accessibility.

    Key Responsibilities

    + Develop and maintain applications using .NET Core (3.1 or higher, 6.0 preferred) and C#.

    + Build and integrate RESTful web services and APIs.

    + Write and maintain complex SQL queries (Select/Insert/Update).

    + Implement functionality for document uploads via web interfaces.

    + Collaborate in Agile/Scrum teams, participating in sprints and ceremonies.

    + Use Git for version control and manage code repositories.

    + Develop unit and regression tests to ensure quality.

    + Work with HTML5, CSS3, JavaScript, and jQuery for front-end development.

    + 6+ years of .NET Core and C# development experience.

    + Strong experience with REST APIs and SQL.

    + Hands-on experience with document upload functionality in web applications.

    + Proficiency in Agile/Scrum methodologies.

    + Experience with Git and code repository management.

    + Solid understanding of unit and regression testing.

    + Front-end skills: HTML5, CSS3, JavaScript, jQuery.

    Nice to Have

    + Familiarity with Web Content Accessibility Guidelines (WCAG).

    + Experience with Azure DevOps/TFS, Jira, or similar tools.

    + Knowledge of secure coding practices (preventing XSS, SQL injection).

    + Experience with SendGrid and identity provider integration (OIDC or SAML).

     

    Job Type & Location

     

    This is a Contract position based out of Lansing, MI.

    Pay and Benefits

    The pay range for this position is $50.00 - $60.00/hr.

     

    Eligibility requirements apply to some benefits and may depend on your job classification and length of employment. Benefits are subject to change and may be subject to specific elections, plan, or program terms. If eligible, the benefits available for this temporary role may include the following:

     

    • Medical, dental & vision • Critical Illness, Accident, and Hospital • 401(k) Retirement Plan – Pre-tax and Roth post-tax contributions available • Life Insurance (Voluntary Life & AD&D for the employee and dependents) • Short and long-term disability • Health Spending Account (HSA) • Transportation benefits • Employee Assistance Program • Time Off/Leave (PTO, Vacation or Sick Leave)

     

    Workplace Type

     

    This is a hybrid position in Lansing,MI.

     

    Application Deadline

     

    This position is anticipated to close on Nov 30, 2025.

    h4>About TEKsystems:

    We're partners in transformation. We help clients activate ideas and solutions to take advantage of a new world of opportunity. We are a team of 80,000 strong, working with over 6,000 clients, including 80% of the Fortune 500, across North America, Europe and Asia. As an industry leader in Full-Stack Technology Services, Talent Services, and real-world application, we work with progressive leaders to drive change. That's the power of true partnership. TEKsystems is an Allegis Group company.

     

    The company is an equal opportunity employer and will consider all applications without regards to race, sex, age, color, religion, national origin, veteran status, disability, sexual orientation, gender identity, genetic information or any characteristic protected by law.

    About TEKsystems and TEKsystems Global Services

    We’re a leading provider of business and technology services. We accelerate business transformation for our customers. Our expertise in strategy, design, execution and operations unlocks business value through a range of solutions. We’re a team of 80,000 strong, working with over 6,000 customers, including 80% of the Fortune 500 across North America, Europe and Asia, who partner with us for our scale, full-stack capabilities and speed. We’re strategic thinkers, hands-on collaborators, helping customers capitalize on change and master the momentum of technology. We’re building tomorrow by delivering business outcomes and making positive impacts in our global communities. TEKsystems and TEKsystems Global Services are Allegis Group companies. Learn more at TEKsystems.com.

     

    The company is an equal opportunity employer and will consider all applications without regard to race, sex, age, color, religion, national origin, veteran status, disability, sexual orientation, gender identity, genetic information or any characteristic protected by law.