Senior Full-Stack Software Engineer

SAGE GROUP PLC; Wokingham; Hybrid; GBP 60,000 - 80,000; Full time

Job summary

A leading financial technology company is seeking a Senior Full-Stack Engineer to join their new UK-based team. In this hybrid role, you will help develop a financial B2B SaaS platform using TypeScript, React, and Node.js, focusing on performance and scalability. Ideal candidates will have over 5 years of experience and a solid background in back-end and front-end development. Join a multicultural environment to innovate and grow in your career.

Qualifications

• 5+ years of professional experience in software development for scalable, web-based applications.
• Proficiency in TypeScript/JavaScript and experience building maintainable applications.
• Proven experience building backend services with Node.js.

Responsibilities

• Take full ownership of the feature development lifecycle.
• Collaborate to translate requirements into user-friendly features.
• Write clean and scalable code for backend and frontend.

Skills

TypeScript

React

Node.js

JavaScript performance optimization

AWS

CI/CD pipelines

Education

Bachelor's degree in Computer Science

Job description

As a Senior Full-Stack Engineer on our new UK-based team, you will help us build a financial B2B SaaS platform using TypeScript, React, and Node.js. You'll tackle our unique challenge: ensuring high performance on an application that handles complex financial calculations and large datasets. With a 60/40 backend-to‑frontend focus, this role is perfect for a proactive engineer who is passionate about building high-performance software throughout the stack and thrives in a multicultural environment. This is a fantastic opportunity to grow your skills while shaping up a new team and a cutting-edge platform.

This is a hybrid position – working 3 days a week from our Winnersh office.

Key Responsibilities

• Take full ownership of the feature development lifecycle, from concept and design to testing and deployment.
• Collaborate with product managers, designers, and other software engineers to translate requirements into well‑architected, user‑friendly features.
• Write clean, scalable, and high‑performance code for both the backend (Node.js) and the frontend (React/TypeScript).
• Collaborate with field teams to support our customers, debug issues, and offer prompt solutions.
• Participate in code reviews and contribute to the continuous improvement of our development processes.
• Improve the performance, scalability and security of the platform.
• Develop and maintain comprehensive tests to ensure software quality and reliability.
• Contribute to our Node.js and AWS backend services.
• Stay up-to-date with the latest trends in web development and cloud‑based SaaS technologies.

Qualifications

• 5+ years of professional experience in software development for scalable, web‑based applications.
• Experience in building large‑scale, maintainable applications, with proficiency in TypeScript/JavaScript.
• Proven experience building and maintaining backend services with Node.js and a common framework (e.g., Fastify, Express, NestJS).
• JavaScript performance optimization – you know how to profile, debug, and refactor code to make it faster.
• Experience in modern frontend frameworks (e.g., React, Vue, Svelte).
• Experience with AWS infrastructure.
• Experience with CI/CD pipelines.
• Bachelor's degree in Computer Science, Software Engineering, or a related field from a university or a leading college.

Bonus Points

• Experience with Browser DB (IndexedDB) and Sync Engine pattern.
• Experience with data‑intensive applications or financial modeling.

Soft Skills

• Strong problem‑solving abilities and an eagerness to learn.
• Excellent communication skills and the ability to work well in a multicultural environment.
• High attention to detail and a commitment to delivering high‑quality work.

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