Team: Product engineering
Reports to: Founders & CEO
Location: Remote worldwide, or in person in the UK
Level: Senior (4+ years)
Type: Full-time
Our mission
Software should do the work. People should do the judgement.
Accounting software is a $23bn market. Accounting services, the actual work of bookkeeping, tax, compliance and advisory, is $720bn. Thirty times bigger, and still done by hand.
Every generation has moved that work somewhere new: paper, then spreadsheets, then the cloud. Each step made it quicker to record; none made it stop being work. We're building the platform that does it instead, with people in the loop only where judgement genuinely matters. We serve small and mid-sized businesses today.
Software has only ever given accountants a better place to do the work by hand. We're taking out the by hand.
What you'd be building
We didn't build software for accounting firms to buy. We own one, and we're automating it from the inside.
Clients don't buy a tool from us and then do their own books. They hire us to do their accounting, and more of that work is done by the platform every month, with qualified people reviewing what matters. The firm is how we reach clients and how we prove the software works. The direction of travel is the software doing nearly all of it.
The product runs all of it: client and lead management, document intake and OCR, invoice and bill processing, an internal double-entry ledger, VAT / MTD / ITSA / CIS compliance, billing, and a client portal. It's deeply integrated with the UK accounting and tax ecosystem, and increasingly driven by AI agents: document extraction, invoice automation, and an in-app assistant.
That structure is why the engineering is different here. We're not shipping a tool and hoping a firm adopts it. We run our own operation on it, so every manual step left in the product is a cost we pay ourselves, and every automation you ship shows up in the business the same week. There's no gap between shipping something and finding out whether it worked.
You'd work on both sides of it: the internal tooling our accountants and bookkeepers work in, and the client-facing product clients log into. This is not a prototype. The firm runs on it today, serving 1000+ businesses, with over £100M in transactions handled and 99.9% uptime. The numbers it produces get filed to HMRC, so correctness is not optional.
The team you'd join
You'd be joining a lean team of accountants, bookkeepers, and full-stack software developers, and working closely with the Founders and CEO directly.
That mix is the point. The people who know how UK accounting actually works sit on the team, and our own practice runs on what we ship, so a domain question gets answered in minutes instead of waiting on a spec, and you can watch someone use the feature you deployed this morning. You don't need to arrive knowing any of it. You do need to want to learn it.
What we need is a senior generalist who can own a feature end-to-end, from the UI through the service layer to the external integration and the background job behind it, and ship it to production without hand-holding. You add throughput and a senior voice in architecture reviews.
What you'll own
- Own features end-to-end. Take a product outcome (e.g. "clients can categorise bank transactions from the portal", "auto-create a payment when an invoice is published") and deliver the whole vertical slice: schema, service logic, API, UI, background jobs, and the integration touchpoints.
- Work across the whole stack. Roughly balanced frontend and backend: typed React on one side, Python services on the other, with background jobs and third-party integrations in between. You should be comfortable living in any of these on a given day.
- Own the external integrations. Build and maintain sync flows, webhook handling, and the data-mapping that keeps our ledger and the accounting and tax platforms we connect to in agreement. Get the edge cases right. This is where correctness bugs hide.
- Contribute to the AI-agent surface. Extend document-extraction and automation workflows built on our agent framework, and the shared service layer they call into.
- Raise the bar on quality. Write tests for the correctness-critical paths, review teammates' PRs, and help us catch phasing and edge-case errors before they reach production.
- Take architecture load off the founders. Be a senior person who can be handed an ambiguous problem and come back with a sound design, not just an implementation.
Layer What we use Backend Modern typed Python: async web framework, ORM, background workers Frontend React / TypeScript (strict), Tailwind CSS, a component library Mobile iOS and Android apps Data A relational database with versioned migrations, plus a cache Auth A managed auth provider, with atomic RBAC Integrations Accounting platforms (Xero), HMRC (MTD / ITSA / VAT / CIS), Outlook, Gmail, banking data, WhatsApp AI Agent orchestration, tool servers, and tracing Infra Managed cloud hosting, Docker, a monorepo with a service-layer architecture
You do not need every item on this list on day one. You do need to be genuinely strong on one of the Python backend or the typed React frontend, and competent and eager on the other.
What we're looking for
The people who do well here don't wait to be handed tickets. You get an outcome and the room to work out the design, the edge cases and everything it takes to get it live, then come back with something better than the brief. What follows is the technical floor, not the job.
Required
- 4+ years building and shipping web applications, with real ownership of features in production (not just tickets handed to you).
- Strong in both a modern typed frontend (React/TypeScript) and a Python web backend. Even if you lean one way, you can hold your own on the other.
- Solid relational-database fundamentals: schema design, migrations, writing and reasoning about non-trivial SQL, and thinking about data integrity.
- Experience integrating third-party APIs (webhooks, OAuth, sync reconciliation, handling partial failure).
- A demonstrable care for correctness: you write tests for the paths that matter, you think about edge cases and idempotency, and you don't ship money-affecting code on a hunch.
- Comfortable working remotely and asynchronously in a small team with high autonomy.
- Experience with accounting, fintech, tax, or other financial-data systems, anywhere a wrong number has real consequences. Familiarity with double-entry bookkeeping, VAT, or the UK accounting-software ecosystem is a significant edge.
- Experience building on or integrating LLM / AI-agent frameworks (agent orchestration, tool use, RAG) beyond calling an API.
- Background-job systems, event-driven architecture.
- You've been an early engineer at a startup and know how to move fast without leaving a mess.
- A CS degree. We care about what you can build and how you reason, not your credential.
- Experience with our exact stack. We care that you're genuinely strong somewhere and quick everywhere else.
This suits people who want a lot of rope. There are few meetings, no ticket queue and nobody tracking your progress. That's freedom if you're self-directed, and uncomfortable if you'd rather be handed a plan.
- Latest practices, no ceremony. We work with current tooling and change it the moment something better comes along. If you've found a faster way to work, you don't need permission to adopt it. What matters is what ships and whether it's right, not whether it followed convention.
- Small, senior, high-trust. Direct access to the founders and to real users. No product manager relaying requirements, no layer between you and the people whose books this affects.
- Correctness culture. We review each other's plans and PRs. We'd rather catch the edge-case bug in review than after it has shipped.
Send a CV plus a short note on one non-trivial full-stack feature you owned end-to-end: what the product problem was, the design decisions and trade-offs you made across the stack, and how you made sure it was correct. Links to shipped work or code we can look at are worth more than a long CV.
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