AI-Driven Legacy Modernisation Engineer

RedRock Resourcing; Reading; On-site; GBP 90,000 - 130,000; Full time

Job summary

RedRock Resourcing is seeking an experienced software engineer to work at the intersection of software engineering, AI and legacy modernisation in Reading. The role is hands-on with complex legacy tech, using modern AI tooling to tackle technical debt and set new coding standards.

You’ll bring a solid C#/.NET foundation and experience with large or legacy systems, plus a track record in AI-assisted development and automated testing.

Qualifications

• Strong software engineering foundation required.
• Deep experience with C#/.NET and legacy systems preferred.
• Familiarity with AI-assisted development and automated testing is a plus.

Responsibilities

• Use AI coding agents to investigate, refactor and modernise legacy codebases.
• Design the engineering harness with proper context, rules and constraints for AI agents.
• Build repository-level instructions, agent skills, prompts and dynamic context.
• Work with Claude Code, MCP and other agentic development tools.
• Establish automated testing and AI evaluation frameworks to ensure quality.
• Build guardrails, sandboxes and CI/CD controls around AI-driven development.

Skills

Software engineering

C#/.NET

AI tooling

Legacy modernization

Tools

Claude Code

Cursor

GitHub Copilot

Codex

Job description

RedRock Resourcing is seeking an experienced software engineer to work at the intersection of software engineering, AI and legacy modernisation in Reading. The role is hands-on with complex legacy tech, using modern AI tooling to tackle technical debt and set new coding standards.

You’ll bring a solid C#/.NET foundation and experience with large or legacy systems, plus a track record in AI-assisted development and automated testing.