Senior Software Engineer - React

👋 Hi! We're OneUp!

Built by a remote team based all over the UK, OneUp is a software platform which provides recruitment and sales teams with the clarity they need to understand and drive performance. Already used by ~350 companies around the world we’re looking for self-starting, ambitious individuals to join our next phase of growth.

🏆 The Role

Our clients love our product, and we love building it for them. To build it better and faster, you’ll be collaborating with the product and engineering teams to deliver new features, refine existing ones, and help shape the architecture that keeps OneUp scalable, reliable, and fast.

As a Senior Software Engineer, you’ll play a key role in guiding technical decisions, mentoring colleagues, and ensuring high engineering standards across the stack. You’ll help drive conversations around architecture, tooling, and performance, ensuring our platform continues to grow sustainably.

You’ll be working primarily with React, TypeScript, PHP, and Laravel, hosted on AWS, within six-week build cycles and continuous deployment.

We believe in empowering engineers with ownership and accountability. You’ll have quarterly goals tied to the initiatives you lead, and your input will directly influence what we build and how we build it.

We value independence but not isolation - pairing, reviews, and open collaboration are part of how we learn and grow together

🚀 Your Responsibilities

• Take ownership of end-to-end feature delivery, from shaping technical design to production release.
• Architect and implement scalable, maintainable systems across the stack.
• Write clean, well-tested, and well-documented code.
• Mentor and support other engineers through pair programming, code reviews, and knowledge sharing.
• Help define and evolve our development practices, tooling, and architecture.
• Collaborate closely with Product, Design, and Delivery to scope and plan upcoming initiatives.
• Investigate and resolve complex bugs or performance bottlenecks.
• Champion technical excellence and pragmatic problem-solving.
• Be proactive in identifying opportunities to improve our platform and processes.

📄 Essential Requirements

• Excellent written and spoken English.
• 5+ years experience working with React (ideally in TypeScript).
• Experience with PHP, Laravel, and MySQL.
• Proven ability to design and deliver well-architected solutions in a team environment.
• Comfortable writing automated tests and reviewing others’ code.
• A track record of mentoring or supporting other engineers.
• Ability to work effectively in a remote, asynchronous setup.
• Must live and have the right to work in the UK

🔑 Desirable Experience

We know it’s tough, but please mind the confidence gap. You don’t have to match the following exactly to be considered for this role:

• Experience with AWS, CircleCI, and GitHub Actions.
• Experience with OLAP Database like Amazon Redshift or Clickhouse.
• Experience in a SaaS or B2B product environment.
• Background in scaling applications and improving performance under load.
• Comfortable working in parallel with multiple engineers on a shared codebase.

💖 Culture & Values

We have five core values we recognise and celebrate across the team:

1. Don't be a d*ckhead - ego, selfishness, unprofessionalism, and alike aren't tolerated at OneUp.
2. Team first, always - the team comes before self, and before the company.
3. Impact over effort - go the extra mile where necessary, but do so in balance.
4. Enjoy the journey - find joy in the day-to-day, not the end destination.
5. Be the change you seek - see a problem? Bring a solution.

We're very protective of the fantastic team we've built here at OneUp, so please forgive us if we're a little picky!

As well as being aligned with our values, we put a lot of importance on having solid soft skills:

• Self-organisation
• Creative thinking
• Comfortable being uncomfortable
• Adaptable/flexible
• Able to be autonomous and use initiative

🙌 Our Offer

• £60,000-£71,000 starting annual salary
• 25 days paid holiday + bank holidays + birthdays off + extra at Christmas (top 10% for time off in the UK)
• Zero-excess, full-cover private health insurance (including dental, visual, and auditory cover)
• Monthly wellbeing budget
• Fully remote with in-person meetups and an annual retreat to keep our culture strong
• A high-performing team without the toxic “hustle or die” mindset
• Clear progression opportunities for those who earn it