Lead Ruby Developer - Inside IR35 - Public Sector

Details

Role: Lead Ruby Developer

Rate: £600 per day outside IR35

Location: Remote

Start date: ASAP

Contract length: Initial contract until 30th October 2026

Project context:

This project focuses on the strategic rewrite of the existing API layer between the GiT CRM and Website platform. The current architecture has created operational and maintenance challenges, and a full rewrite is required to deliver a scalable, maintainable, and long-term solution.

The proposed approach will separate the API into two distinct components:

• A CRM-facing API responsible for interfacing directly with CRM data and services.
• A facade layer responsible for interfacing with wider platform services including GiT, GSE, and Apply.

This decoupled architecture will improve system resilience, simplify testing, reduce dependencies between systems, and minimise the impact of future CRM changes on wider business platforms. It will also provide a cleaner foundation for future development and integration work.
The initial phase of the project is focused on technical discovery, architecture planning, and documentation. An experienced Architecture Technical Lead is required to lead this phase, including the production of technical plans, system diagrams, API specifications, and delivery planning. The intention is for this individual to continue into the delivery phase of the API rewrite alongside additional contracted development resources, ensuring continuity and minimising knowledge loss between discovery and implementation.
This work is considered critical prior to commencing development, as it will define project scope, identify technical dependencies, determine resource requirements, and establish delivery timelines.

Discovery & Documentation Phase Deliverables
During the initial discovery phase, the developer will be responsible for:

• Producing detailed data flow diagrams covering CRM and platform integrations
• Defining the target architecture and integration approach
• Writing API specifications for:
• The CRM REST API
• The GiT Facade API
• Producing Swagger/OpenAPI documentation
• Supporting project estimation, resourcing, and implementation planning

Required Skills & Experience

The ideal candidate will have:

• Strong Back End Ruby/Ruby on Rails development experience
• Proven expertise in API design and development
• Experience producing API specifications using Swagger/OpenAPI
• Experience working with CRM integrations and complex system integrations
• Technical architecture and documentation experience
• The ability to lead technical discovery through to delivery
• Experience working collaboratively in open, cross-functional environments