Founding Engineer

Harrison Clarke; San Francisco (CA); On-site; USD 180,000 - 320,000; Full time

Benefits offered by this job

Founding equity

Flexible work arrangements

Job summary

Harrison Clarke is partnering with a well-funded, early-stage AI-native fintech company building the next generation of B2B financial infrastructure. As Founding Engineer you will join the founding team to design, build and scale the core platform with significant ownership over technical decisions and product direction.

This high-impact role is ideal for an engineer who thrives in ambiguity, moves quickly and wants to leave a lasting mark on an early-stage company, with flexible working

Qualifications

• Senior or staff engineer with a track record building production fintech systems.
• Hands-on AI/ML systems in production, especially LLMs, agents, and retrieval/workflow systems.
• Comfort operating in an early-stage environment with high ownership and rapid iteration.
• Excellent product sense and ability to balance technical excellence with business impact.

Responsibilities

• Design and implement core platform services and AI-powered workflows that automate complex B2B financial processes.
• Build and own backend systems, data pipelines and integrations with banking, payments and financial data providers.
• Collaborate with founders and product to translate customer needs into robust, scalable technical solutions.
• Establish engineering best practices, architecture standards and development processes as the team grows.
• Contribute to the evaluation and integration of LLMs, agent frameworks and other AI technologies into production systems.
• Ensure security, reliability, compliance and auditability of systems handling sensitive financial data.

Skills

Python

Go

TypeScript/Node

Distributed systems

AI/ML in production

Job description

Founding Engineer – AI-Native Fintech B2B Platform

Harrison Clarke is partnering with a well-funded, early-stage AI-native fintech company building the next generation of B2B financial infrastructure. The platform uses large language models, agentic workflows and real-time data systems to automate complex financial operations, including payments, reconciliation, risk, compliance and treasury management, for mid-market and enterprise businesses.

This is a rare founding engineering role at a Tier 1 VC-backed startup operating at the intersection of applied AI and fintech. You will join as one of the first technical hires and help define the product, architecture and engineering culture from the ground up.

The Role

As Founding Engineer you will work side-by-side with the founding team to design, build and scale the core platform. You will have significant ownership over technical decisions, product direction and the systems that power the company’s AI-first approach to financial automation.

This is a high-impact, hands-on role suited to an engineer who thrives in ambiguity, moves quickly and wants to leave a lasting mark on an early-stage company.

Key Responsibilities

• Design and implement core platform services and AI-powered workflows that automate complex B2B financial processes
• Build and own critical backend systems, data pipelines and integrations with banking, payments and financial data providers
• Collaborate closely with founders and product to translate customer needs into robust, scalable technical solutions
• Establish engineering best practices, architecture standards and development processes as the team grows
• Contribute to the evaluation and integration of LLMs, agent frameworks and other AI technologies into production systems
• Ensure security, reliability, compliance and auditability of systems handling sensitive financial data

What We’re Looking For

• Proven experience as a senior or staff-level engineer with a track record of building production systems in fintech, financial infrastructure, payments or related domains
• Strong backend engineering skills (e.g. Python, Go, TypeScript/Node, or similar) and experience designing scalable, reliable distributed systems
• Hands-on experience with AI/ML systems in production, particularly LLMs, agents, retrieval systems or workflow automation
• Comfort operating in an early-stage environment with high ownership, rapid iteration and evolving requirements
• Excellent product sense and the ability to balance technical excellence with business impact

Nice to Have

• Prior founding, early-stage or 0-to-1 engineering experience
• Experience with agentic frameworks, tool-calling systems or multi-step AI workflows
• Background in regulated environments (fintech, banking, payments)
• Exposure to real-time data systems, event-driven architectures or high-throughput financial processing

What the Company Offers

• Founding-level equity with meaningful ownership
• Opportunity to shape product, architecture and engineering culture at a Tier 1 VC-backed AI fintech
• Direct collaboration with experienced founders
• High-impact work at the frontier of AI and financial infrastructure
• Flexible working arrangements and a supportive early-stage environment