Founding Engineer

A pre-seed, founder-led startup is seeking a Founding Engineer to build the "Agentic Financial Ops" layer for the global fintech market.

While others build simple chatbots, this stealth-mode venture is embedding autonomous AI agents directly into major B2B platforms—automating invoicing, bill pay, and payroll for SMBs.

This is an opportunity to join at the ground floor of a company targeting a $100B market shift.

What you will build:

  • The Engine: A white-label, API-first, multi-tenant system designed to embed cleanly and securely into partner ecosystems.
  • The Intelligence: You aren’t just calling APIs; you are treating LLMs as infrastructure. You will build agentic workflows that handle complex financial operations autonomously.
  • The Foundation: You will replace the founder’s initial "vibe-coded" prototype with a robust, production-ready architecture. You decide the stack; you set the engineering culture.

The Founders:

  • The Commercial Engine: A domain experts and "straight talkers" (formerly VPs at a successful embedded finance scale-up). They have already secured signed contracts across the UK, US, and Europe—and early revenue—before the API is even live. They bring the pipeline, the deep market knowledge, and the capital; you bring the product.

The Role:

  • Zero to One: Take the product from MVP concept to Production.
  • Full Ownership: Build the core platform end-to-end (Backend, APIs, Frontend).
  • Architecture: Design for security, permissions, and scale from day one.
  • Speed: Iterate fast with real customers. The goal is to launch the API in Q2.

This is not a ticket-taking role at a stagnant SaaS. This is a Decide + Build + Own seat where you sit directly beside the founder.

The Profile

  • Mindset: Scrappy, high-growth, and product-minded. You care deeply about why a feature exists, not just how it’s built.
  • Experience: A Senior Engineer (Backend-leaning or Full-stack) who has shipped early-stage products into production.
  • Tech: Hands-on experience with LLMs & agentic workflows. You are pragmatic about tech choices that optimize for speed and correctness.

The Offer Salary £95k–£120k + Significant Founding Equity.

Job Details

Company
numi
Location
City of London, London, United Kingdom
Posted