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# C# Backend Senior Engineer (London-based)

- **Company:** gb
Itransition
- **Location:** London, UK (Remote available)
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** .NET Framework, Application Programming Interfaces (APIs), Artificial Intelligence, Automation of Tests, C Sharp (Programming Language), Distributed Systems, Neo4j, OAuth, OpenID, Role-Based Access Control, Redis, JSON Web Token, Policy as Code, Istio, Backend, Kubernetes, Apache Kafka, Api Gateway, Restful APIs, Microservices
- **Published:** September 30, 2026
- **Apply:** https://www.totaljobs.com/job/senior-engineer/itransition-job108057635

## About the Role

* 5+ years of experience with C#/.Net
 * REST APIs
 * Microservices architecture
 * OAuth2, JWT, OIDC
 * Graph modeling
 * Distributed systems
 * Understanding of RBAC, ReBAC, ACL, and policy evaluation is a plus

Nice to have:

 * Hands-on experience with Identity & Authorization
 * Experience with policy engines / policy-as-code
 * Experience with API Gateway, Kubernetes, Service Mesh
 * Neo4j
 * OpenFGA
 * SpiceDB
 * OPA
 * Redis
 * Kafka

## Description

We are looking for a C# backend engineer to join the Authorization team. In this role, you will work on creating the Identity & Authorization Platform. You will build the authorization platform used across all products: SDKs, Policy APIs, authorization microservices, and identity services., * Develop Authorization SDKs

 * Evolve Policy APIs
 * Create and maintain Authorization microservices
 * Develop Identity services
 * Implement RBAC, ReBAC, ACL, and policy evaluation
 * Build graph relationships, permission inheritance, and delegated administration
 * Build integrations with API Gateway, AI Gateway, Kubernetes, and Service Mesh
 * Write automated tests, authorization regression suites, and performance tests