Integration Developer C#,.Net (SC Cleared, Public Sector)

Integration Design: Collaborate with business stakeholders, IT teams, and external partners to gather integration requirements and define workflows. Design data mappings, transformations, APIs, and message schemas to…

Pay rate £600 – £650/day
Contract type Contract
Posted 23 September 2026

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About this contract

Integration Design:
Collaborate with business stakeholders, IT teams, and external partners to gather integration requirements and define workflows. Design data mappings, transformations, APIs, and message schemas to facilitate the secure and efficient exchange of data between systems.
Development and Implementation:
Design, develop, test, and deploy integration solutions using C#, .NET, or similar programming languages. Build RESTful APIs and backend services to support integration needs. Configure connectors and implement robust error handling and retry mechanisms to ensure reliability and data integrity.
Integration Platforms and Tools:
Utilize integration platforms such as Azure Logic Apps, Azure Data Factory, SSIS, or other middleware tools to orchestrate data flows and integrate diverse systems. Experience with tools such as Postman, Swagger, and API gateways is highly desirable.
API and Service Integration:
Build and maintain APIs (REST and/or SOAP), working with authentication, authorization, and secure data exchange. Integrate internal and third-party APIs to facilitate service-oriented and event-driven architecture across systems.
Data Transformation and Mapping:
Implement data transformation logic to convert between formats like JSON, XML, and CSV. Design reusable components and mappings to streamline data flow between systems with different schemas or protocols.
Testing and Debugging:
Perform unit, integration, and end-to-end testing of integration workflows and APIs. Debug issues using tools such as Fiddler, Postman, and application logs. Continuously optimize performance and reliability through code refactoring and system tuning.
Documentation and Reporting:
Document API contracts, integration configurations, and solution architecture to support maintainability. Provide progress updates, technical summaries, and risk reports to stakeholders throughout the project lifecycle.
Collaboration and Communication:
Work closely with software developers, data engineers, QA teams, and business analysts to align integration work with broader project goals. Clearly communicate technical designs, project updates, and roadblocks to both technical and non-technical stakeholders.Continuous Learning:
Keep up-to-date with integration frameworks, cloud technologies, and development best practices. Actively participate in knowledge-sharing sessions and contribute to the continuous improvement of integration standards and code quality

Preffred candiadte should be from

HM Revenue & Customs (HMRC)
Department for Work and Pensions (DWP)
Home Office
Ministry of Defence (MOD)
Ministry of Justice (MOJ)
HM Treasury
Department for Education (DfE)
Department for Transport (DfT)
Department of Health and Social Care (DHSC)
Department for Environment, Food & Rural Affairs (DEFRA)
Department for Science, Innovation & Technology (DSIT)
Foreign, Commonwealth & Development Office (FCDO)

GCS is acting as an Employment Business in relation to this vacancy

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