Backend Software Engineer .Net Java Low Latency

Client Server Ltd.; Greater London; Hybrid; GBP 80,000 - 90,000; Full time

Benefits offered by this job

25 days holiday

Pension

Life Assurance

Income protection

Private Medical

Dental care

Gym subsidy

Wellness apps

Cycle to work

Stock options

Family leave

Sabbaticals

Training budget

Job summary

Client Server Ltd. in London is seeking a Backend Software Engineer to join an Agile team working on a Greenfield Market Data platform. The role centers on the .Net/Java stack, low latency, and high throughput processing in AWS.

You will collaborate across DevOps and Product teams, contributing to system design and API development. Hybrid working is offered with four days in the City office and one day remote. Expect a strong focus on performance, scalability, and continuous learning.

Qualifications

• Strong C#/.Net skills with SOLID, DRY and KISS principles.
• Experience with high throughput, low latency systems.
• Experience building APIs.
• SQL experience.
• Knowledge of Terraform and IaC.
• AWS cloud experience.
• Familiar with Java and open to learning.
• Comfortable using AI tools to boost productivity.
• Collaborative with strong communication and mentoring abilities.

Responsibilities

• Collaborate with DevOps and Product Management in an Agile team on a Greenfield Market Data platform.
• Provide subject matter expertise on the .Net stack and contribute to technical design discussions.
• Work with Java, and data processing tech like Apache Flink for large-scale workloads.
• Contribute to CI/CD pipelines and AWS deployment practices.
• Mentor junior developers and support team collaboration.

Skills

C#/.Net

APIs

Low latency

Mentoring

Tools

Terraform

AWS

Java

Job description

Backend Software Engineer .Net Java Low Latency

London, Greater London | £80k - £90k per year

Backend Software Engineer / Developer (C# .Net Java Low Latency) London to £90k

Are you a technologist who enjoys contributing to technical discussions and using the best tool for the job?

You could be progressing your career at a global, financial Market Data provider whilst enjoying a range of perks and benefits.

What's in it for you:

• Salary to £90k + bonus
• 25 days holiday
• Pension, Life Assurance and Income protection
• Private Medical and Dental care
• Gym subsidy and wellness apps
• Cycle to work scheme
• Ability to buy stock options
• Family leave and sabbaticals
• Continuous training and career development including personalised budget

Your role:

As a Backend Software Engineer you will collaborate with DevOps and Product Management within an Agile team environment working on a Greenfield Market Data platform. The platform has been built with C# deploying to AWS and requires high scalability and low latency - they currently handle 40 billion messages per day.

You'll work across the full development lifecycle, from requirements and design through to production, providing subject matter expertise on the .Net stack and contributing to technical design discussions. You'll use a range of technology including Apache Flink with Java for large scale data processing and will be able to assess and recommend new and emerging technologies, using the best tool for the job.

Location / WFH:

You'll join colleagues in the City office four days a week with flexibility to work from home once a week.

About you:

• You have strong C# .Net skills and a good understanding of design patterns such as SOLID, DRY and KISS Design Principles
• You've worked on systems that require high throughput, low latency and scalability and understand the challenges involved (finance experience not required)
• You have strong experience of building APIs
• You have SQL experience
• You have a good understanding of CI/CD and Infrastructure as Code (Terraform)
• You have cloud experience with AWS
• You're familiar with other languages such as Java and are open to learn new things
• You're comfortable with using agentic AI and tools to help improve productivity
• You're collaborative with great communication skills, happy to mentor more junior developers