Sr. Software Developer – Application Migration & Modernization ( 102-08SENG-01)
This role modernizes legacy .NET applications and their data tiers onto supportable platforms. Most engagements start with a working-but-aging system — a .NET Framework 4.8 application backed by Oracle — and end with something maintainable, scalable, and testable on PostgreSQL RDS with Windows application servers on EC2. This is hands-on engineering with real constraints: production systems that can't go down, undocumented application logic, business logic buried in stored procedures nobody has read in a decade, and a migration that needs to be seamless and invisible to end users. Critically, this is not a database-only migration: the application layer itself must be modified to support PostgreSQL as the backend, not just have its data moved underneath it. Given the scope and timeline, this engagement also relies on effective use of AI coding agents to accelerate discovery, testing, and code translation — not as a replacement for engineering judgment, but as a working part of the delivery process.
What you will do
Assess existing .NET Framework applications — dependencies, integration points, data access patterns — and produce a realistic modernization plan with sequencing and risk called out.
Modify the application codebase itself to support PostgreSQL as the backend, beyond just migrating the underlying data.
Untangle and port data access layers, including legacy ADO.NET and older Entity Framework code,
