Senior Full-Stack .NET Modernization Engineer

Simon & Schuster; New York; Hybrid; USD 130,000 - 170,000; Full time

Job summary

Simon & Schuster is modernizing its core order management, fulfillment, partner integration, and financial systems using .NET and SQL. The Full-Stack .NET Developer role focuses on replacing legacy COBOL batch programs with modern services and web front ends, validating AI-generated output, and ensuring production readiness.

The position emphasizes building scalable services, applying established patterns, and contributing to engineering standards while collaborating with QA and legacy

Qualifications

• 5+ years of professional full-stack .NET development.
• Experience using AI tools to assist development with judgment to validate output.
• Strong SQL Server / T-SQL skills including stored procedures and performance fundamentals.
• Back-end service experience with worker services and batch processing.
• Front-end web development using ASP.NET Core or React/Angular.
• Production mindset with observability and safe deployment practices.
• Strong debugging and problem-solving skills and data-difference reasoning.
• Clear written communication for design notes and operational docs.

Responsibilities

• Build modern replacements by implementing .NET worker services, APIs, and T-SQL stored procedures replacing legacy COBOL batch programs.
• Review and refine AI-generated code with engineering judgment to ensure correctness and maintainability.
• Apply target architecture patterns: structured logging, telemetry, and configuration-driven behavior.
• Support validation and cutover by instrumenting replacements and driving packages through QA gates.
• Resolve complex conversion issues by comparing legacy and new implementations with legacy specialists.
• Develop and maintain modern web UI components for new workflows replacing legacy green-screen apps.
• Contribute to engineering standards by capturing lessons learned and improving shared templates.

Skills

Full-stack .NET development

AI-assisted development

SQL Server / T-SQL

Back-end services

Front-end web development

Production mindset

Debugging & problem solving

Clear written communication

Tools

Dapper

Entity Framework Core

Azure

Job description

Simon & Schuster is modernizing its core order management, fulfillment, partner integration, and financial systems using .NET and SQL. The Full-Stack .NET Developer role focuses on replacing legacy COBOL batch programs with modern services and web front ends, validating AI-generated output, and ensuring production readiness.

The position emphasizes building scalable services, applying established patterns, and contributing to engineering standards while collaborating with QA and legacy