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Client Server

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68 jobs

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68 jobs Posted Sort

Client Server Limited

Backend Software Engineer Python - Technologist

Backend Software Engineer joining the R&D team of a cybersecurity firm that uses AI to defend against AI-based attacks, building a new greenfield product. Mostly backend Python with some Rust/TypeScript/C++ and cloud (AWS/Azure/GCP); hybrid role based in the Cambridge office two days a week. Salary to £80k plus bonus.

AI AWS Azure C++ Cybersecurity +5 skills

Client Server Limited

Backend Software Engineer Python R&D

Backend Python engineer in the R&D team of a Cambridge cybersecurity firm building a greenfield product to combat AI-based security attacks. Day to day is rapid prototyping and platform development, mainly in Python with exposure to Rust and cloud platforms, hybrid from the Cambridge office twice a week.

AI AWS Azure C++ Cybersecurity +5 skills

Client Server Limited

Senior Python Backend Engineer - AI Cybersecurity

Build a greenfield AI-driven cybersecurity product at Client Server Limited: as Senior Python Backend Engineer you will rapidly prototype ideas, tackle complex problems, and deliver robust backend services using Python and cloud platforms, ideally with some Rust, TypeScript, or C++ exposure.

AI Cloud C++ Cybersecurity Prototyping +3 skills

Client Server Limited

Senior C# Backend Engineer – Real-Time Trading Systems

UKFull-timeSenior

Senior backend engineer joining a London-based trading engine team to design and build real-time trading systems and own Greenfield projects alongside the strategy team. Core stack is C#/.NET with ASP.NET and SQL/Oracle, plus some JavaScript/React; full-time onsite in the City office.

C# .NET JavaScript Oracle React +1 skills

Client Server Limited

Python Backend Engineer — Cybersecurity R&D (Greenfield)

Client Server Limited is hiring a Python backend engineer to build a greenfield product in its cybersecurity R&D team near Cambridge, UK. Day to day is Python backend development with the chance to explore Rust and emerging technologies, in a hybrid setup with two office days per week in Cambridge.

Backend Software Engineer Python - Technologist

Backend software engineer joining a Cambridge-based cybersecurity company that uses AI to protect clients worldwide from advanced cyber threats. The role focuses on backend development in Python, with Rust and C++ also central to the stack; salary up to £80k.

AI C++ Cybersecurity Python Rust

Client Server Limited

Real-Time Backend Engineer (Go/Node Pub/Sub) - Remote + Equity

Builds and owns the backend of a real-time messaging platform in Go and Node.js, designing scalable distributed pub/sub systems with a focus on performance and reliability. Mostly remote with occasional London office meetups, Slack collaboration, and monthly tech talks.

Distributed Systems Node.js Slack

Client Server Limited

Backend Engineer - C# .NET Core | FinTech (Newcastle)

Backend engineer building high-performance C# .NET Core services and distributed systems that handle large data volumes for a FinTech client, onsite in brand-new Newcastle offices. The role covers the full SDLC with flexible hours and a focus on quality, robust software.

C# Distributed Systems .NET Fintech SDLC

Client Server Limited

Backend Developer Golang Node Pub / Sub

Backend Developer building the core real-time messaging platform of a high-growth tech company, designing scalable pub/sub and distributed systems in Go or Node.js. Mostly remote with monthly meetups at a dog-friendly North London office, plus work on low-latency messaging and AI communication infrastructure.

AI Cloud Distributed Systems Event Driven Architecture Go +5 skills

Client Server Limited

London Backend Engineer (C#/.NET) - Sports Trading, Onsite + Bonus

Backend Engineer (C#/.NET) joining a sports trading team onsite in London, building robust backend systems, APIs and data flows for high-availability trading. Core stack: C#/.NET, ASP.NET, and SQL or Oracle.

API C# .NET Oracle SQL

Backend Software Engineer Python R&D

Backend Software Engineer (Python, R&D) for a cybersecurity technology company that uses AI to protect clients globally from advanced cyber threats. The role involves problem solving on complex backend systems and pays up to £85k, based in London/Cambridge with work-from-home flexibility.

AI Cybersecurity

Client Server Limited

Backend Engineer TypeScript – Remote/WFH Cyber Security

Builds and owns TypeScript backend services for a cybersecurity company's customer portal, taking features from rapid prototype to production-ready systems with a security focus. Hybrid role: two days per week in the Cambridge office, the rest working from home.

Client Server Limited

Python Backend Engineer – AI Security R&D (Cambridge)

A Python backend engineer joins the R&D team in Cambridge to build a new greenfield product that combats AI-based security threats, delivering complex backend systems through rapid prototyping and iterative development, mainly in Python with exposure to Rust and TypeScript, in a hybrid work arrangement.

AI Prototyping Python Rust TypeScript

Client Server Limited

Front Office C++ Backend Engineer - London Hybrid to £125k

Senior C++ backend engineer building a core equity trading system for front-office desks in London. Day-to-day is C++17/20 on Linux tackling low-latency, high-volume data challenges alongside traders. Hybrid role (one day a week from home), paying up to £125k plus bonus.

C++ Design Patterns Linux

Client Server Limited

Backend Engineer (C#/.NET) - Trading Systems, London

Backend engineer building high-performance trading systems in C#/.NET with SQL for a hedge fund technology team in London, collaborating with quantitative researchers on valuation and pricing components and owning projects from design through delivery.

Client Server Limited

Backend Developer Typescript - Cyber Security

Backend Developer designing and building TypeScript backend services for the customer portal at a leading cyber security technology company in Cambridge (hybrid, 2 days/week in office), protecting organisations from AI-driven cyber threats. Stack includes TypeScript and Kubernetes, with Python/Rust desirable.

AI Containerization Cybersecurity Kubernetes Python +2 skills

Client Server Limited

Backend Software Engineer Python R&D

Backend Software Engineer in an R&D team at a cybersecurity technology business, building a Greenfield product to combat AI-based attacks. Day to day is rapid prototyping and iterative development, mainly in backend Python with some Rust and other emerging technologies; hybrid role based in London (2 office days/week), salary up to £85k plus bonus.

AI AWS Azure C++ Cybersecurity +5 skills

Backend Software Engineer Python R&D

Join an R&D team building a greenfield backend product that counters AI-based security threats. The role is primarily Python (with Rust/exposure to other languages), spanning rapid prototyping, architecture, and deploying/scaling on cloud platforms (AWS/Azure/GCP). London-based with WFH.

AI AWS Azure Cloud C++ +5 skills

Backend Software Engineer C++ Python - Trading

A backend engineer builds and optimizes data-driven systems in C++ and Python that power systematic trading strategies, collaborating with senior engineers and quantitative researchers in a Linux environment at a tech-led trading firm.

C++ Linux Python

Client Server Limited

Backend Software Engineer C++ Python - Trading

UKFull-timeLead

Hands-on backend engineer at a systematic trading firm in London, designing, implementing and optimising C++ and Python components that power proprietary, data-driven trading strategies, collaborating with experienced engineers and quantitative researchers. Office-based Monday-Friday near St James Park; salary up to £125k.

C++ Linux Python

90K – 125K £