Senior Software Engineer (AI)

We’re Capital on Tap 👋

💳 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. We set out to fix that.

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 £1 billion in funds within its first year, and a growing suite of tools and financial products that make running a small business easier.

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!

📈Check out the development opportunities in the Software Engineering team

🏢This is a Hybrid role, the Software Engineering Team works from our London (Moorgate) Office 2 days per week

AI Engineering at Capital on Tap

We're building a small team of ~3 AI-specialist software engineers who embed directly within product teams to deliver intelligent features. Rather than operating as a separate unit, you'll work alongside existing teams as an internal consultant, helping them deliver AI-powered capabilities whilst building their skills through hands-on collaboration and structured training. Part of the role has a hand in upskilling the wider Engineering department through workshops, documentation, and knowledge transfer.

What You’ll Be Doing

You'll partner with product teams to build and deliver AI features, working embedded within their squad structure. Your role is to enable teams to successfully deliver AI capabilities while upskilling them to own the features long-term.

You’ll build robust and scalable solutions using .Net technology

From the first line of code to production, monitoring, and continuous improvement - you’ll own the SDLC

Teamwork makes the dream work - you’ll partner with Product Managers, QA’s, and fellow Software Engineers

You’ll build bulletproof unit and integration tests to keep our software sharp and our users happy

Bugs happen. When they do, you’ll be ready to troubleshoot and tweak as needed

You’ll bridge the gap between tech speak and business goals, ensuring everyone’s on the same page and moving forward together

We’re Looking For 🔎

Required skills

4+ years hands-on experience in C#, .NET Core

Good testing practices, in both Unit and Integration testing

Good understanding of database technologies

Experience in using Agile development practices

A passion for learning new skills and technologies

A proactive, supportive, and collaborative team player

Nice to have

Experience sharing knowledge through training sessions or workshops, helping other teams get the most out of tools or systems you've built.

Practical experience building backend applications or service wrappers that integrate with AI APIs or LLMs

Interview Process 🤝

First stage: 30-minute intro, CV review, and values with Talent Partner

Second stage: 45-minute “Tech Chat” with our Engineering Manager

Final stage: 90-minute Code Pairing + 30-minute Values Interview

Diversity & Inclusion 🌈

We welcome, consider and encourage applications from anyone who shares our commitment to inclusivity. Join us in creating a space where authenticity thrives, and everyone can do their best work.

Other Info

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📧Email careers@capitalontap.com if you have any questions.

Excited to work here? Apply!

If you’d like to progress your career within our fast growing, profitable fintech then click apply and we will aim to get back to you within 3 working days (during busy periods this could take up to 5 working days.)