Our client is an early-stage London-based startup building an AI-native platform for finance operations, starting with accounts receivable and revenue collection. The product replaces manual, spreadsheet-driven workflows with intelligent systems that understand contracts, usage, and payments—and automate revenue end to end. This is foundational infrastructure at the intersection of AI, billing, contracts, and financial data, designed for modern, usage-based businesses.

You’ll join at the earliest stage as a Founding Engineer, with ownership over architecture, AI systems, and platform direction.

What you’ll do:

• Own the architecture of the core AI-driven platform, from data ingestion to invoicing, collections, and reconciliation
• Build AI systems that interpret contracts, usage data, and operational signals, turning unstructured inputs into reliable financial outputs
• Take AI systems from prototype to production, including model serving, evaluation, monitoring, and failure handling in business-critical workflows
• Design backend and infrastructure foundations with a focus on correctness, auditability, scalability, and observability
• Act as a Staff-level technical leader, setting engineering standards, making long-term architectural decisions, and shaping the product roadmap alongside the founders
• Ship directly to customers, iterating quickly based on real usage and feedback

What we’re looking for:

• experience building production-grade backend, platform, or AI systems 
• Strong systems thinking across data models, workflows, APIs, and distributed systems
• Hands-on experience deploying and operating LLMs or applied ML systems in real products
• Proven ownership of complex technical decisions in ambiguous, early-stage environments
• Interest in financial systems, billing, or revenue infrastructure (nice to have, not required)
• Ability to work in person in London four days per week

If you’re passionate about building AI-native infrastructure at the core of real businesses then, apply today.