This is a job that Jill, our AI Recruiter, is recruiting for on behalf of one of our customers.
She will pick the best candidates from Jack's network
The next step is to speak to Jack.
Job Title: Founding Engineer
Salary: £100-130k + 0.6-0.8% Equity
Company Description: Spinal - VC-backed AI automation for modern finance teams
Job Description:
As the third founding engineer at this London Bridge-based startup, you will build agentic AI systems that automate complex accounts receivable workflows. You'll transform unstructured contracts into live invoicing and revenue recognition engines, working directly with the founders to replace manual spreadsheets with deterministic, AI-driven financial infrastructure in a fast-paced, in-office environment.
Location: London, UK
Why this role is remarkable:
Join as employee #5 with a true founding equity stake and direct influence over the architectural evolution of the core product.
Build at the cutting edge of agentic AI using LangGraph and Temporal to solve high-stakes, multi-billion dollar problems in finance.
Work in a high-intensity, collaborative environment in London Bridge with a team that prioritizes shipping fast and weekly demo sessions.
What you will do:
Design and deploy agentic AI systems that extract complex billing terms from unstructured legal documents and PDFs.
Architect and maintain robust backend services using Python, Pydantic, and Postgres to power end-to-end collections and revenue recognition.
Collaborate directly with the CTO to translate customer needs into production-ready features that eliminate manual finance workflows.
The ideal candidate:
3-5 years of experience as a Python backend engineer with a proven track record of shipping complex systems from zero to one.
Hands-on expertise with agentic AI frameworks such as LangGraph or LangChain, specifically for processing unstructured data into structured outputs.
A founding mindset demonstrated through previous early-stage startup experience, academic distinction, or a high-performance background in competitive fields.
Who are Jack & Jill?
Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.
And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate.
Next steps
Step 1. Visit our website.
Step 2. Click 'Talk to Jack'.
Step 3. Talk to Jack so he can understand your experience and ambitions.
Step 4. Jack will make sure Jill (the AI agent working for the company) considers you for this role.
Step 5. If Jill thinks you're a great fit and her client wants to meet you, they will make the introduction.
Step 6. If not, Jack will find you excellent alternatives. All for free.
We never post fake jobs
This isn't a trick. This is an open role that Jill is currently recruiting for from Jack's network.
Sometimes Jill's clients ask her to anonymize their jobs when she advertises them, which means she can't share all the details in the job description.
We appreciate this can make them look a bit suspect, but there isn't much we can do about it.
Give Jack a spin! You could land this role. If not, most people find him incredibly helpful with their job search, and we're giving his services away for free.
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