Principal Architect in London

Principal Architect in London

London Full-Time No working from home possible
Prism Digital
Principal Architect | TypeScript, Node, Python | Global Environmental Data Non-Profit Powering Investment Decisions
Location: Hybrid, 2 days a month in the London office
Must-have: hands‑on engineering depth and platform‑wide architecture leadership, not one or the other
The platform here has grown fast, and integration across services has got messy with it: systems that work but don’t talk to each other cleanly, with little in the way of defined contracts or shared standards. This client is hiring their first ever Principal Architect to sort that out properly, reporting straight into the CTO. They’re a purpose‑led organisation sitting at the intersection of data, climate and global finance, running one of the world’s most widely used environmental disclosure systems, relied on by tens of thousands of companies and institutions to report impact and shape investment decisions.
It’s a global team, and the London office is a key engineering hub: a tight‑knit group of tech leads and platform specialists working closely together. You’ll split your time between architecture and code, working directly with those tech leads across squads. The job is to make the current state legible, define where it needs to go, and help teams get there without slowing delivery down. There’s real ownership here, both technically and in how engineering standards evolve across the business.
One thing worth being clear on, because it’s the whole point of the role. This is not a job for a pure delivery engineer who’s only ever built individual systems, and it’s not a job for an enterprise architect who lives in governance documents and diagrams. You need both. The architecture leadership to document a complex multi‑team estate, define integration standards and a target state, drive down technical debt, and build a roadmap that several engineering teams can align behind. And the engineering depth to get into the code, reverse‑engineer how the existing integrations actually work, and understand the historical decisions behind them. If you’ve led architectural change at scale but lost touch with the code, or you’re a strong senior engineer who hasn’t yet owned architecture across an organisation, this one isn’t for you.
What They’re Looking For:
Platform‑wide architecture leadership (initiatives spanning multiple teams and products, not single systems)
Current and target‑state architecture (documenting a complex estate and defining where it goes)
Integration standards and governance (service boundaries, contracts, shared engineering principles)
Technical debt reduction and multi‑year roadmaps (aligning several engineering teams behind one direction)
Hands‑on engineering (still in the code, reverse‑engineering live integrations and historical design)
TypeScript and Node.js
System design (distributed, end‑to‑end platforms)
What You’ll Work With:
React and Next.js
Nest.js
Python
API integrations (internal and third‑party)
Nice to Haves:
Experience standing up a Principal Engineer or Platform Architect function from scratch
Track record taking a fast‑grown platform and bringing its integration under control
Mentoring or growing a senior engineering group
Why Join?
The pull here isn’t the tech, it’s the mandate. You’ll be the first person ever to hold this seat. You’ll start by mapping what exists and where it breaks down, then introduce an integration model that squads will actually adopt, not a theoretical architecture exercise. From there it’s building reference implementations, shaping how APIs get designed, and lifting the developer experience across the whole platform. Because it’s the first role of its kind in the business, the expectation is it grows into a small group of senior engineers over time, so you’d have a genuine say in how that function takes shape.
Employee Benefits:
Generous non‑contributory pension
Life assurance
Employee Assistance Programme
Training and development support
Flexible working arrangements
Prism Digital

Contact Details:

Prism Digital Recruitment Team