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- Tasks: Lead architecture decisions and mentor teams to build impactful fintech solutions.
- Company: Join a mission-driven fintech transforming SME finance for the better.
- Benefits: Enjoy remote work, 25 days holiday, life assurance, and discounts with top retailers.
- Why this job: Shape the future of finance while making a real difference for UK SMEs.
- Qualifications: Must have 2+ years as a Principal Engineer or similar role in fintech.
- Other info: Collaborate with major banks and influence key platform decisions.
The predicted salary is between 43200 - 72000 £ per year.
We’re working with a mission-driven fintech that’s solving a massive problem: small businesses — the backbone of the UK economy — are still underserved by traditional finance. This company is changing that, helping banks and lenders make faster, smarter, fairer credit decisions using real-time financial data.
Already trusted by 80+ major banks and lenders, they’re scaling fast — and now they’re looking for a Principal Engineer to shape the next stage of their platform and lead from the front.
Why This Role is Great
- You’ll architect the core of the platform used by major UK banks and lenders
- Get in early enough to influence big decisions — but with real traction already proven
- Work across multiple product teams, mentoring, guiding, and building alongside them
- Blend strategy and code — be the go-to technical voice in the room
- Remote-first with the flexibility to come together in London when it counts
- Genuinely meaningful work: better finance access for 5.5 million UK SMEs
What You’ll Be Doing
- Lead architecture decisions and make them real — from developer-friendly APIs to scalable platform components
- Guide cross-functional teams (frontend, backend, QA) with your experience and technical instincts
- Collaborate closely with product, design, and commercial teams to build solutions that actually solve real problems
- Balance pragmatism with perfection — make things work first, then make them beautiful
- Mentor senior engineers and help scale a top-class team
- Be a visible, respected voice across the business, bringing clarity and confidence to complex tech questions
- Help shape hiring, team growth, and long-term engineering strategy
Tech Snapshot
- Languages: Java, Kotlin, JavaScript
- Frontend & Frameworks: React, Spring, Temporal
- Databases: PostgreSQL, MongoDB
- Cloud: AWS (heavy use), with IaC (Terraform)
- Practices: TDD, CI/CD, clean architecture, pragmatic testing
Bonus Points: Data engineering or machine learning experience
What They’re Looking For
- A Principal Engineer, Tech Lead, or Software Architect with at least 2 years at this level
- You’ve built and scaled SaaS platforms — ideally in fintech or data-heavy domains
- You’re a hands-on problem-solver who can step back, see the big picture, and then guide others through it
- You’re confident working with stakeholders from execs to product managers — turning complexity into clarity
- You care deeply about engineering craft, team health, and customer impact
- You can mentor senior engineers and inspire confidence across the org
Perks & Benefits
- Remote-first role with London-based meetups (office in Shoreditch)
- 25 days holiday + public holidays
- Life assurance (4x salary)
- Pension contribution
- Virtual GP & wellbeing support
- Perks & discounts with top retailers (ASOS, Tesco, Amazon, etc.)
- Referral bonus scheme
- Regular socials & team events
Ready to Lead with Purpose? If you’re a Principal Engineer who loves shaping product direction, building great tech, and mentoring high-performing teams — this is your moment to lead from the front and make a difference. Message me for a confidential chat or send over your CV — let’s talk.
Principal Engineer (City of London) employer: numi
Contact Detail:
numi Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Principal Engineer (City of London)
✨Tip Number 1
Familiarise yourself with the fintech landscape, especially focusing on how small businesses interact with financial services. Understanding the unique challenges SMEs face will help you articulate your vision and solutions during discussions.
✨Tip Number 2
Showcase your experience in building and scaling SaaS platforms by preparing specific examples of past projects. Be ready to discuss how you’ve led architecture decisions and collaborated with cross-functional teams to deliver impactful solutions.
✨Tip Number 3
Highlight your mentoring experience by sharing stories of how you've guided junior or senior engineers in previous roles. This will demonstrate your leadership skills and your commitment to team growth, which is crucial for this position.
✨Tip Number 4
Prepare to discuss your approach to balancing pragmatism with perfection in engineering. Be ready to provide examples of how you've made tough decisions that prioritised functionality while still aiming for high-quality outcomes.
We think you need these skills to ace Principal Engineer (City of London)
Some tips for your application 🫡
Tailor Your CV: Make sure your CV highlights relevant experience in fintech, SaaS platforms, and team leadership. Emphasise your hands-on architecture skills and any experience with the technologies mentioned in the job description.
Craft a Compelling Cover Letter: Write a cover letter that showcases your passion for improving SME finance and how your background aligns with the company's mission. Mention specific projects where you've made impactful architectural decisions or led teams successfully.
Showcase Technical Skills: In your application, clearly outline your technical expertise, especially in Java, Kotlin, and cloud technologies like AWS. Provide examples of how you've applied these skills in previous roles to solve complex problems.
Highlight Mentorship Experience: Since the role involves mentoring senior engineers, include examples of how you've guided and developed talent in your past positions. This will demonstrate your leadership capabilities and commitment to team growth.
How to prepare for a job interview at numi
✨Understand the Company’s Mission
Before the interview, make sure you grasp the company's mission of improving finance access for SMEs. This will help you align your answers with their goals and demonstrate your passion for their cause.
✨Showcase Your Technical Expertise
Be prepared to discuss your experience with the technologies mentioned in the job description, such as Java, Kotlin, and AWS. Highlight specific projects where you've successfully implemented these technologies to solve complex problems.
✨Demonstrate Leadership Skills
As a Principal Engineer, you'll be expected to lead teams and mentor others. Share examples of how you've guided cross-functional teams in the past and how you approach team dynamics to foster a positive working environment.
✨Prepare for Scenario-Based Questions
Expect questions that assess your problem-solving abilities and decision-making process. Think of scenarios where you've had to balance pragmatism with perfection, and be ready to explain your thought process and outcomes.
