Senior .NET Developer (Legacy System Migration Exp)

Title: Senior .NET Developer (Legacy System Migration Exp)

Location: Onsite/Hybrid (Miami-Dade County, FL)

Type: Contract

Duration: 6 months

Note : Looking for Local candidates only OR local to Florida

Job Description:

About the Role:

• We are seeking an experienced Senior .NET Developer with a strong background in legacy system modernization and data migration to join our team supporting Miami-Dade County initiatives.
  The consultant will play a key role in transitioning legacy systems (PEN, MS Access, Mainframe) into the GoldKey platform, ensuring data integrity, system integration, and compliance with county, environmental, and regulatory standards

Key Responsibilities:

• Migrate and modernize legacy applications and databases into the GoldKey platform.
• Ensure data accuracy, validation, and integrity throughout migration processes.
• Integrate Impervious Surface Reviews into Paving and Drainage workflows to optimize Building Permit processes.
• Develop and implement automated workload assignment and process automation features to streamline operations.
• Design, build, and maintain .NET applications using C#, ASP.NET MVC, and related frameworks.
• Collaborate with county analysts, business users, and vendors to meet compliance and regulatory requirements (environmental, historical preservation, and sewer permits).
• Develop and optimize PL/SQL queries, stored procedures, and database structures for performance and reliability.
• Support reporting and ETL processes using SSIS and SSRS.
• Maintain strong documentation and adhere to secure coding and data governance best practices.

Required Skills & Experience:

• 8 10 years of hands-on experience in C# / .NET Framework development.
• Strong understanding of Object-Oriented Programming (OOP) principles and debugging practices.
• Expertise in JavaScript, jQuery, AJAX, and asynchronous programming for dynamic web applications.
• Proficient in Oracle PL/SQL and SQL Server, with proven ability to optimize queries and design normalized databases.
• Experience implementing MVC architecture and security best practices.
• Familiarity with Windows and Web Services, including RESTful / SOAP APIs and authentication mechanisms.
• Strong experience with SSIS (ETL) and SSRS (reporting) for data transformation and analytics.
• Hands-on experience migrating legacy systems (e.g., MS Access, Mainframe) to modern applications.
• Prior experience working on government or municipal projects (county, city, or state level) is highly preferred.
• Excellent written and verbal communication skills with the ability to collaborate effectively with cross-functional teams.