Role: Senior Full-Stack Developer
Location: London (Hybrid – 3 days in-office per week)
Start Date: ASAP
Day Rate: £550 p/d (Outside IR35)
About the Company
A fast-growing UK-based organisation is building software to support the delivery of high-integrity environmental solutions. Their clients include major developers and infrastructure providers, and the company is scaling rapidly. A core focus is on developing reliable internal tooling for pricing, compliance, quoting, and stock availability.
The Opportunity
They’re looking for a hands-on Senior Full-Stack Engineer to take ownership of the first production-ready version of their quoting and automation platform. This includes database design, backend development, and a robust front-end that internal teams can rely on daily. You’ll be responsible for architecture, implementation, deployment, and ensuring reliability from day one.
Key Responsibilities
Quoting & Optimisation Engine
* Implement logic for pricing BNG/NN units, including rule-based calculations (e.g. adjacency, trading caps).
* Build systems that intelligently allocate available stock based on multiple constraints (e.g. location, pricing).
* Ensure pricing models are fully traceable and auditable for compliance.
Automation & Data Pipelines
* Automate tasks like stock updates, KPI reporting, and pricing refreshes.
* Refactor internal data sources into structured, versioned SQL-backed models.
* Develop helpers to process geographic and regulatory data layers (e.g. GIS overlays).
User-Facing UI
* Build a reliable, performant front-end for non-technical commercial users.
* Develop middleware to surface business insights.
* Implement role-based access control, usage tracking, and exportable outputs (PDF/CSV).
Platform Engineering & Security
* Set up authentication (SSO preferred), RBAC, audit trails, and security best practices.
* Own CI/CD pipelines, infrastructure as code, and system monitoring from the start.
Tech Stack & Experience
Essential
* Strong full-stack background: TypeScript with React (or similar), Python (FastAPI) or Node.js (NestJS).
* Data: PostgreSQL preferred; solid experience with schema design, migrations, and performance tuning.
* Cloud/DevOps: Azure or AWS, Docker, GitHub Actions, IaC tools (Terraform/Pulumi).
* Security-first mindset: OAuth/OIDC, token auth, logging, and secure architecture.
* Testing & Docs: Confident with writing tests, documenting APIs, and delivering production-grade systems.