Founding Backend Architect - Regulated Fintech Core Banking

Dex; Greater London; On-site; GBP 120,000 - 190,000; Full time

Job summary

Dex is seeking a founding engineer to architect and own the full tech stack for a regulated fintech platform in London. From concept to production, you’ll shape the core banking platform, security, and scalability, partnering with the founder to translate ambitious ideas into robust, compliant systems.

You will recruit and set engineering culture, owning infrastructure, data integrity, and reliability in a hands-on, growth-stage environment.

Qualifications

• 5-12 years of engineering experience, with deep expertise in backend systems, infrastructure, and production architecture.
• Proven track record building complex, highly regulated financial infrastructure (e.g., core banking, ledger systems, payments).
• Experience as a founding engineer, early hire, or senior engineer scaling a high-growth fintech or infrastructure company.
• Expertise in distributed systems, cloud infrastructure, data integrity, reliability, and security.
• London-based or willing to relocate, and committed to in-person collaboration.

Responsibilities

• Architect, build, and secure the entire core banking platform from first principles.
• Own all technical decisions: infrastructure, backend systems, data integrity, and product engineering.
• Translate complex regulatory requirements into scalable, resilient, and compliant financial systems.
• Drive the product from initial concept through to production, ensuring security and reliability.
• Define the engineering culture and recruit the foundational engineering team.

Skills

Backend systems

Distributed systems

Cloud infrastructure

Security

Production architecture

Tools

Job description

Dex is seeking a founding engineer to architect and own the full tech stack for a regulated fintech platform in London. From concept to production, you’ll shape the core banking platform, security, and scalability, partnering with the founder to translate ambitious ideas into robust, compliant systems.

You will recruit and set engineering culture, owning infrastructure, data integrity, and reliability in a hands-on, growth-stage environment.