Responsibilities
- Design and build robust, scalable back-end services in C#/.NET.
- Own the full SDLC, from feature inception through production, monitoring, and continuous improvement.
- Contribute to mobile development across iOS and Android using Flutter, Kotlin, and/or Swift.
- Collaborate with Product, Design, and QA from early feature shaping through delivery.
- Write thorough unit and integration tests and uphold high engineering standards.
- Identify bottlenecks and drive improvements across the team.
- Work cross-functionally, bridging technical decisions with business goals.
Qualifications
- Strong back-end engineering experience, ideally in C#/.NET.
- Mobile development experience in Flutter/Dart, Kotlin, or Swift – a firm requirement.
- Solid testing practice across unit and integration testing.
- Experience with CI/CD platforms such as CodeMagic or similar.
- Comfortable working in Agile environments.
- Autonomous and collaborative – you take ownership and see things through.
Tech Stack
- Backend: C#, .NET, .NET Core
- Mobile: Flutter, Dart, Riverpod, GoRouter, Kotlin, Swift
- Databases: SQL Server, MongoDB, Firestore
- Cloud: GCP (Firebase) and Azure
- CI/CD: CodeMagic
Capital on Tap started because small businesses were underserved. Big banks were slow, their products weren't fit for purpose, and small business owners often couldn't access what they needed. Today we're a financial platform – not just a credit card company. We offer a best-in-class business credit card, SME-focused spend management platform, a savings product that hit £1billion in funds within its first year, and a growing suite of tools and financial products that make running a small business easier.
We have over 1,000 employees, £20bn in annual card spend, 200,000+ customers, 17,000+ Trustpilot reviews averaging 4.7 stars, and we're profitable. We've done a pretty good job so far, but we're just getting started!
This is a hybrid role. The team works from our London offices two days per week.
The Team
The Banking and Repayments teams sit at the heart of Capital on Tap's product, owning the core account experience for thousands of small business customers. Banking manages account operations, transaction lifecycles, balance management, ClearBank integration, and savings. Repayments owns the repayment rails, including the most recent open banking repayments.
We value engineers who take genuine ownership, work autonomously, and bring depth across the stack. This is a high-priority hire with real impact from day one.
We try not to take ourselves too seriously (all the time), so we make sure our office is decked out with a pool table, arcade machine, beer tap, and a couple of office dogs thrown in for good measure.
Benefits
- Private Healthcare including dental and opticians services through Vitality
- Worldwide travel insurance through Vitality
- Anniversary Rewards (£250, £500, £750, 4-week fully paid sabbatical)
- Salary Sacrifice Pension Scheme up to 7% match
- Octopus EV Salary Sacrifice Scheme
- 28 days holiday (plus bank holidays)
- Annual Learning and Wellbeing Budget
- Enhanced Parental Leave
- Cycle to Work Scheme
- Season Ticket Loan
- 6 free therapy sessions per year
- Dog Friendly Offices
- Free drinks and snacks in our offices
Software Engineer - Banking in City of Westminster employer: Capital on Tap
At Capital on Tap, we pride ourselves on being an excellent employer that fosters a collaborative and innovative work culture. Our London-based team enjoys competitive benefits such as private healthcare, 28 days of holiday, and a dedicated learning budget to support professional growth. Join us to be part of a dynamic environment where your contributions directly impact our mission and success.
