Founding Engineer (Full Stack); Patch to CTO
We're hiring Terrapin's first engineer. You'll take custody of a live, SOC 2-certified fintech platform, run tests and CI/CD on it, and own the roadmap from there, with a clear path to CTO.
We usually respond within a day
I'm looking for our founding engineer!
The person who takes a live, paying fintech product and makes it truly ours.
We build receipt-and-proof automation for the self-employed: the app quietly finds your receipts (email, bank feeds, camera roll, texts), sorts them, matches them to your bank transactions, and produces accountant-ready exports. It's live on iOS and Android, it's SOC 2 certified, and people are paying for it. The model works.
I need one person who treats this codebase as theirs, ships fast, and owns the platform end-to-end. This is a founding engineer role with a real path to CTO.
Your first job is to take the keys.
Move the platform off the agency's Azure into ours, take custody of production, and the headline deliverable.
Build the automated test suite this codebase never had, with a CI/CD pipeline where a green build genuinely means "safe to ship." Then you own the roadmap.
How we build matters as much as what we build.
We are not rebuilding an IT shop of tickets and manual QA.
Terrapin runs as an AI-native pod: Claude Code and agents do the repetitive work and produce tested, PR-ready changes; you own architecture, review, security, and the hard 20%.
AI gives you the velocity, your tests and pipeline are what keep that velocity from turning into breakage!
We want to ship multiple times a week and almost never break anything, and hold our SOC 2 line the whole way. If that model excites you rather than worries you, you're the person.
This is genuinely full-stack.
Strong .NET / C# backend on Azure, real ownership of infra, security, and DevOps, and polished mobile (React Native + Expo, iOS and Android); Because the app is the product. Testing isn't someone else's job here. It's the core discipline.
The kind of person whose teammates would describe as:
an owner, not a ticket-taker
obsessive about shipping quality fast
calm owning production for a product with real money moving through it
someone who builds automation instead of doing the same thing twice
security-minded by instinct, not as an afterthought
What you'd bring:
Senior+ .NET / C# backend, PostgreSQL, solid API design
Real Azure ownership: App Services, networking, Key Vault, identity, CI/CD (Azure DevOps or similar)
Strong React Native + Expo mobile, with genuine UI/UX taste
Test automation and CI/CD as a way of life — you write the tests with the code
Hands-on building with Claude Code / agent tooling, and doing it safely in a SOC 2 world
Bonus points: fintech / payments background, Plaid experience, or applied LLM work.
And the reason the right engineer will actually stay: receipts are just the wedge. We're building toward a verifiable, tamper-evident record of an economic event. Proof that banks, insurers, and AI agents can consume directly. Stripe is a payment rails. We're building proof rails.
You'd work directly with me every day — 18+ years in fintech and payments, two exits behind me — so you own the engineering but never carry the hard architecture, security, or product calls alone.
The details:
UK or EU-remote(temporarily), with solid overlap to UK hours and business trips.
We're genuinely open to strong candidates across both. Being open to relocating to the UK down the line is a plus, but not a day-one requirement.
Competitive base plus real founding-level equity.
One hard line: you build quality in through tests and CI/CD. We're deliberately leaving the manual-testing, hope-it-works world behind, and a dev who treats testing as optional isn't the hire. Everything else, we can talk about.
If you want founder-level ownership, a CTO trajectory, and an AI-native way of building, and owning a live fintech platform from week one lights you up, let's talk.
Apply and tell me about something you shipped that you're proud of, and one thing you broke and how you made sure it never happened again.
- Locations
- London
- Remote status
- Temporarily Remote
- Employment type
- Full-time
- Employment level
- Executive / Senior Level
About Voxquill
We are a candidate-first talent boutique for startups and high-growth tech companies. We continuously scout for senior operators, executive leaders, and founding team members to place them directly into the core DNA of early-stage startups across the US and Japan.