C# Backend Senior Engineer (London-based)

Itransition; Greater London; Hybrid; GBP 70,000 - 110,000; Full time

Benefits offered by this job

Flexible working hours

Career development system

Competitive compensation

Job summary

Itransition is seeking a skilled C# backend engineer to join the Authorization team. You will help build the Identity & Authorization Platform used across products, including SDKs, Policy APIs, authorization microservices, and identity services.

Office remote United Kingdom with flexible hours and a focus on scalable, secure access control across multiple projects.

Qualifications

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

Responsibilities

• 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

Skills

C#/.Net

REST APIs

OAuth2/JWT/OIDC

RBAC/ReBAC/ACL

Graph modeling

Distributed systems

Tools

Neo4j

OpenFGA

SpiceDB

OPA

Redis

Kafka

API Gateway

Kubernetes

Service Mesh

Job description

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.

office remote United Kingdom

Requirements

• 5+ years of experience with C#/.Net
• REST APIs
• 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

Responsibilities

• 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

We offer

• Projects for such clients as PayPal, Wargaming, Xerox, Philips, Adidas and Toyota
• Competitive compensation that depends on your qualification and skills
• Career development system with clear skill qualifications
• Flexible working hours aligned to your schedule