Senior .NET/C# Developer (Oracle to PostgreSQL migration) – Finance – Remote

Duration: 6 months

Rate: £500 – £600

Start: ASAP

My client is looking for a Senior Developer to join the team to help with a migration. They are undertaking a strategic transformation of a legacy system built on PHP and Oracle, migrating to a modern architecture using PostgreSQL and .NET (C#). This is not a simple lift-and-shift; the project involves re-engineering over 240 Oracle stored procedures, some highly complex, into performant, maintainable C# code. The new system will coexist with the legacy platform during the transition, requiring careful integration and support for business-as-usual (BAU) operations.

Key Responsibilities

Collaborate with the existing team to re-engineer Oracle PL/SQL stored procedures into C# services. Design and implement .NET-based components that integrate with both legacy PHP systems and new PostgreSQL databases. Work closely with business analysts and stakeholders to ensure functional parity and identify opportunities for enhancement. Participate in the design of a hybrid architecture that supports phased migration. Use AI-assisted tools to analyse, translate, and optimize legacy code. Support BAU operations during the migration period, ensuring system stability and continuity. Contribute to code reviews, testing strategies, and documentation.

Required Skills & Experience

5+ years of experience in .NET/C# development, with a strong focus on backend services and data access layers. Proven experience in migrating legacy systems, especially from Oracle to PostgreSQL or similar. Strong understanding of PL/SQL and experience translating stored procedures into application logic. Familiarity with PostgreSQL, including performance tuning and SQL dialect differences. Experience working in hybrid environments where legacy and modern systems coexist. Comfortable using AI tools (e.g., GitHub Copilot, ChatGPT, code translators) to assist in development and migration tasks. Solid understanding of software architecture, design patterns, and integration strategies. Excellent communication skills and ability to work collaboratively in a cross-functional team.

Desirable Skills

Experience with PHP, especially in legacy systems. Familiarity with DevOps practices, CI/CD pipelines, and containerization (Docker/Kubernetes). Exposure to domain-driven design and microservices architecture. Experience in agile development environments.

*Rates depend on experience and client requirements

Job InformationJob Reference: JO-2507-354873Salary: £500 - £600 per daySalary per: dayJob Duration: 6 months Job Start Date: ASAPJob Industries: Software EngineeringJob Locations: Greater LondonJob Types: Contract