Senior Fullstack Engineer

iO Associates; London; On-site; GBP 90,000 - 110,000; Full time

Job summary

An innovative FinTech powerhouse is seeking a Senior Full Stack Developer to join their dynamic team. This role offers the chance to work on cutting-edge trading products and contribute to building scalable, client-facing solutions using modern JavaScript technologies. You'll have the opportunity to influence the architecture and performance of world-class trading platforms while collaborating with global teams. If you thrive in a fast-paced environment and are passionate about technology, this is a career-defining opportunity that promises growth and impact.

Benefits

Competitive salary plus bonus scheme

Flexible working hours

25 days holiday plus bank holidays

Learning and development opportunities

Qualifications

• Experience in designing and developing full stack applications.
• Strong knowledge of React.js and Node.js.

Responsibilities

• Design and develop robust full stack applications using React.js and Node.js.
• Collaborate with global teams to deliver innovative features.

Skills

React.js

Node.js

JavaScript

Full Stack Development

Software Lifecycle

Job description

Title: Senior Full Stack Developer (React & Node)

Salary: Up to £110,000 D.O.E

Location: London (Hybrid)

iO Associates is working with a global FinTech powerhouse that's leading the charge in delivering high-performance electronic trading platforms for institutional clients - and they're now looking for a Senior Full Stack Developer to join their growing engineering team!

This is a fantastic opportunity to take ownership of a cutting-edge trading product and play a key role in building scalable, client-facing solutions using modern JavaScript technologies.

What you'll be doing:

• Designing and developing robust full stack applications using React.js (v16+) and Node.js
• Working directly with proprietary trading engines to create high-performance tools
• Building white-label trading platforms tailored to client needs
• Collaborating with global trading and research teams to deliver innovative features
• Contributing across the full software lifecycle, from design to production support

What you'll get:

• Competitive salary plus bonus scheme
• Flexible working hours
• 25 days holiday plus bank holidays
• Learning and development opportunities
• And more!

This is a career-defining role where you'll have real influence over the architecture, performance, and evolution of a world-class trading solution. If you thrive in a fast-paced, high-impact environment - this one's for you.

If you're interested in this role or know someone who would be, then please apply to this advert and email a. methula@ ioassociates.co. uk