Senior C# Developer

We are seeking a Senior Engineer to design and deliver features for a large, long-lived .NET desktop product. You will collaborate with a team of senior developers, transforming rough briefs into fully functional screens, application code, database changes, and optimized queries, ensuring timely delivery. You will take full ownership of features—from deciding how they work to building and maintaining them in production. Our development process incorporates AI tools like Cursor and Claude to enhance productivity, with every change owned by the developer who merges it.

Key Responsibilities

- Own features end-to-end, including interaction design, screen development, business rules, data modeling, query optimization, and daily user-facing details.
- Design and build user interfaces using Windows Forms and HTML/CSS/JavaScript screens embedded via Microsoft WebView2 within the desktop application.
- Write and maintain production C# code, ensuring stability, architectural consistency, and continuous improvement of touched code.
- Bridge communication between the desktop host and embedded web screens by managing messaging between C# and JavaScript, synchronizing data flow and UI consistency.
- Manage database tasks such as designing tables and indexes, creating safe migration scripts, and tuning slow queries and reports to handle real-world data volumes.
- Develop and maintain operational reports and exports, including grids, formatted documents, and spreadsheet outputs.
- Support background processing and manage releases across live customer environments.
- Utilize AI coding tools responsibly to accelerate development, crafting prompts carefully, reviewing all changes thoroughly, and shipping only code you fully understand.
- Integrate AI features judiciously, ensuring clear data boundaries and avoiding the inclusion of customer or personal data in prompts, logs, or third-party tools.
- Provide accurate estimates based on code review, prioritize work to deliver usable slices early, communicate risks promptly, and adjust scope to meet user needs and deadlines.

Required Qualifications

- Strong, current production experience with C# and the .NET framework.
- Expertise in Windows Forms, including designer-based screens, user controls, data-bound grids, and UI-thread management.
- Proficiency with Microsoft WebView2, including hosting, configuration, C# and JavaScript interoperation, and handling navigation, lifecycle, and security.
- Solid skills in HTML, CSS, and JavaScript sufficient to design and build embedded web screens that are responsive and visually consistent with the desktop UI.
- Experience with SQL Server, including schema and index design, execution plan analysis, query tuning, and writing safe migration scripts.
- Proven ability to maintain large Windows Forms applications and improve performance by analyzing execution plans, adding indexes, and rewriting queries without altering results.
- Experience designing screens, application code, and database components cohesively for the same feature.
- Background in modernizing desktop applications by integrating web screens alongside existing Windows interfaces.
- Daily use of AI coding tools with disciplined review processes to ensure generated code adheres to product standards.
- A track record of committing to and delivering releases, including managing regressions, data fixes, and final user requirements before go-live.
- Strong security practices, ensuring credentials are excluded from source code and logs, and handling customer and personal data in compliance with regulations.

Preferred Qualifications and Benefits

- Experience or education related to education, training, or student-information systems.
- Familiarity with reporting, spreadsheet export, document generation, messaging, or file storage within a .NET desktop environment.
- Background in performance optimization for large reporting databases and background job processing.
- Experience with automated testing for pure logic and manual testing for UI components where automation is not feasible.

You will join a team of senior developers with significant autonomy over design and implementation decisions within your domain. New development follows established product patterns, while legacy areas receive careful, incremental improvements. We value early communication of risks and prefer scope adjustments over missed deadlines.

This role offers ownership of impactful features in a product with real users and lasting value, collaboration with experienced colleagues for design and code review, and the use of modern AI-assisted tools as a standard part of daily work.