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Product Engineer (Backend-Leaning) | Python, TypeScript, AWS | Billing, Pricing & Commercial Platforms | Energy / Trading | UK Remote | £500-550/day | 3-6 months | Outside IR35 at Owen Thomas | B Corp™, United Kingdom, £500-£550 per day

£500 - £550 per day

Outside Spy
Remote (United Kingdom)
Aug 04, 2026

Duration not stated Information Technology

Contract Description

The Company

We're partnering with an ambitious technology business building software within a highly regulated, data-intensive industry, where billions of data points, complex business rules and commercial workflows need to be processed accurately and at scale.

They're now looking for an experienced Product Engineer to help build the next generation of their commercial platform, with a particular focus on billing, pricing, settlements and high-volume transactional systems.

This is an opportunity to join a small, high-calibre engineering team where you'll have genuine ownership, influence technical direction, and solve challenging engineering problems from first principles.

You'll join a product-focused engineering team building business-critical systems that sit at the heart of the platform.

This is a backend-first role (Python ≈70%) with exposure across the full stack, working on software responsible for complex commercial calculations, billing workflows, pricing logic and large-scale transactional processing.

Success in this role requires engineers who enjoy understanding complicated business domains, modelling real-world commercial rules and building highly reliable systems where correctness is just as important as performance.

Designing and owning backend services in Python
Building scalable billing, pricing and commercial platform functionality
Developing APIs and workflows that process high volumes of transactional data
Modelling complex business rules and financial calculations
Working closely with Product to design solutions from first principles
Contributing across the stack where appropriate (TypeScript)
Improving reliability, scalability and engineering standards as the platform evolves

This is a pragmatic Product Engineering environment where engineers are trusted to own problems end-to-end and make meaningful technical decisions.

Python
TypeScript
AWS
PostgreSQL
Modern API Architecture
Distributed Systems
CI/CD

5+ years of commercial software engineering experience
Strong production-grade Python
Experience building billing, settlement, pricing or payments platforms
Experience within the Energy sector, Utilities, Commodity Trading or Financial Trading is highly desirable
Comfortable working with data-heavy systems and complex business logic
Strong product mindset with a high level of ownership
Excellent communication and collaboration skills
Experience within startup or scale-up environments is advantageous

Experience building platforms where transactional integrity, financial accuracy and scalability are business critical will be particularly valuable.

A collaborative interview process focused on practical engineering, product thinking and problem solving.

Fully remote within the UK
Work on highly complex commercial systems with genuine engineering challenges
High ownership with direct influence on product and architecture
Small, experienced engineering team
Modern technology stack
£500-550/day

If you've built billing engines, pricing platforms, settlement systems or other complex transactional software - and ideally have experience within the energy or trading sectors - this is an opportunity to apply that expertise to a product where your work will have a significant real-world impact.

Apply with your CV and we'll be in touch if there's alignment.

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