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- Tasks: Design and build full-stack solutions that make a real impact on user experience.
- Company: Join OnBuy, one of the UK's fastest-growing tech companies.
- Benefits: Competitive salary, flexible working, and opportunities for personal growth.
- Other info: Collaborative environment with a focus on learning and career advancement.
- Why this job: Be part of a dynamic team creating meaningful change in an evolving marketplace.
- Qualifications: Experience in full-stack development and a passion for innovative solutions.
The predicted salary is between 60000 - 80000 ÂŁ per year.
Who are OnBuy? OnBuy are an online marketplace who are on a mission of being the best choice for every customer, everywhere. We have recently been named one of the UK's fastest-growing tech companies in the Sunday Times 100 Tech list. All achievements we are very proud of, but we don't let that go to our head. We are all laser focused on our mission and understand the huge joint effort ahead of us needed to succeed.
Working at OnBuy: We are a team of driven and motivated people who thrive when working at pace. To succeed at OnBuy you need to take charge and fully own your responsibilities, rolling your sleeves up when needed to 'get it done'. Working at OnBuy you are surrounded by so much opportunity, but you must possess the ability to stay focused and prioritise ruthlessly. Most importantly, you will thrive in an ever-changing environment as we are constantly evolving. At OnBuy, you're not just a number or another cog in a machine. We are creating something really special, and you have the opportunity to affect meaningful change and have your voice heard. We are a close team, who have the opportunity to learn and grow as OnBuy evolves.
This is a critical role responsible for building, scaling, and evolving OnBuy’s core commerce platform across both front-end and back-end systems. As a Senior Full Stack Engineer, you will own engineering delivery end-to-end; from customer-facing experiences to underlying services and data systems. You will operate within a cross-functional team and be accountable for shipping high-quality, scalable solutions that directly impact GMV, seller performance, and customer experience. This role moves beyond “front-end vs back-end” you are an Engineer responsible for outcomes, not layers.
- End-to-End Engineering Ownership
- Design, build, and maintain full-stack solutions across UI, APIs, and backend systems
- Translate product requirements, designs, and wireframes into scalable, production-ready systems
- Own features from concept → development → testing → release → monitoring
- Front-End Excellence
- Build responsive, high-performance user interfaces using modern JavaScript frameworks
- Translate UI/UX designs into clean, maintainable code
- Optimise applications for speed, scalability, and usability
Senior Full Stack Engineer employer: OnBuy Limited
Contact Detail:
OnBuy Limited Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Senior Full Stack Engineer
✨Tip Number 1
Network like a pro! Reach out to current employees at OnBuy on LinkedIn or other platforms. Ask them about their experiences and any tips they might have for the interview process. This insider info can give you a leg up!
✨Tip Number 2
Show off your skills! Prepare a portfolio or GitHub repository showcasing your best projects, especially those that highlight your full-stack capabilities. When you get the chance to chat with the team, share these examples to demonstrate your expertise.
✨Tip Number 3
Be ready to discuss real-world problems! OnBuy values practical solutions, so think of challenges you've faced in past roles and how you tackled them. This will show you're not just about theory but can deliver results in a fast-paced environment.
✨Tip Number 4
Apply through our website! It’s the best way to ensure your application gets seen by the right people. Plus, it shows you’re genuinely interested in being part of the OnBuy team. Don’t miss out on this opportunity!
We think you need these skills to ace Senior Full Stack Engineer
Some tips for your application 🫡
Show Your Passion: When writing your application, let your enthusiasm for the role and our mission shine through. We want to see that you’re not just looking for a job, but that you genuinely care about being part of our journey at OnBuy.
Tailor Your CV: Make sure your CV is tailored to the Senior Full Stack Engineer role. Highlight your relevant experience and skills that align with what we’re looking for. We love seeing how your background can contribute to our team!
Be Clear and Concise: Keep your application clear and to the point. We appreciate straightforward communication, so avoid fluff and focus on what makes you a great fit for the position. Remember, we’re busy too!
Apply Through Our Website: Don’t forget to apply through our website! It’s the best way for us to receive your application and ensures you’re considered for the role. Plus, it’s super easy to do!
How to prepare for a job interview at OnBuy Limited
✨Know Your Tech Stack
Make sure you’re well-versed in the technologies mentioned in the job description. Brush up on your knowledge of modern JavaScript frameworks and back-end systems. Be ready to discuss how you've used these technologies in past projects and how they can be applied at OnBuy.
✨Showcase Your Problem-Solving Skills
Prepare to discuss specific challenges you've faced in previous roles and how you overcame them. OnBuy values engineers who can take charge and own their responsibilities, so highlight instances where you rolled up your sleeves to get things done.
✨Demonstrate Your Team Spirit
Since OnBuy is a close-knit team, it’s important to show that you can thrive in a collaborative environment. Share examples of how you’ve worked effectively within cross-functional teams and contributed to meaningful change in your previous roles.
✨Embrace Change and Adaptability
OnBuy is constantly evolving, so be prepared to discuss how you handle change. Talk about times when you had to adapt quickly to new requirements or technologies, and how you prioritised tasks in a fast-paced environment.