Senior Backend Engineer: Real-Time, Secure Platform

Outerlimit Group Ltd.; Greater London; Hybrid; GBP 90,000 - 120,000; Full time

Benefits offered by this job

Equity

Flexible working

Job summary

Outerlimit Group Ltd. in London (King's Cross) and New York City seeks a Senior Backend Engineer to design and build core platform capabilities for real-time control, security, and observability in agentic systems.

You will create high-performance backend services in critical execution paths and contribute to system design and security. You will own features end-to-end, mentor peers, and push for low-latency, reliable solutions while collaborating with frontend, ML, DevOps and platform teams to

Qualifications

• 5+ years' professional software engineering experience.
• At least 2+ years at a larger tech company or equivalent.
• Current strong mid-level with track record of end-to-end ownership.
• Experience on request-path systems (APIs/gateways).
• Ability to mentor and grow into a senior role.

Responsibilities

• Design and build scalable backend services for real-time control.
• Develop systems for request flows, enforcement logic, and real-time decisioning.
• Work with authentication/authorisation protocols (OAuth/OIDC).
• Integrate with identity providers and external platforms.
• Write high-quality, observable, secure production code.

Skills

Backend engineering

C#/.NET

SQL

Cloud (Azure/AWS)

Education

BSc in Computer Science

Tools

Azure

SQL Server

Git

Job description

Outerlimit Group Ltd. in London (King's Cross) and New York City seeks a Senior Backend Engineer to design and build core platform capabilities for real-time control, security, and observability in agentic systems.

You will create high-performance backend services in critical execution paths and contribute to system design and security. You will own features end-to-end, mentor peers, and push for low-latency, reliable solutions while collaborating with frontend, ML, DevOps and platform teams to