Principal Fullstack Engineer

FlightStory; Greater London; On-site; GBP 120,000 - 180,000; Full time

Job summary

Steven.com is seeking a Principal Engineer - Fullstack in London to set the technical bar for the ITO and own the architecture of the company’s highest-stakes systems. You will partner with the CITO and VP Eng to drive AI-native product foundations and scalable pipelines.

You will mentor senior and junior engineers, shape long-term strategy, and contribute to core platform decisions that impact the creator economy.

Qualifications

• Experience designing large-scale distributed systems in production.
• Strong full-stack proficiency across front-end and back-end technologies.
• Experience architecting AI/ML systems, LLM-powered workflows, or intelligent pipelines.

Responsibilities

• Define and uphold architectural standards across the engineering org.
• Lead design discussions and make high-stakes technical decisions.
• Mentor engineers and drive rigorous code reviews.
• Translate ambiguous bets into concrete technical plans with clear tradeoffs.

Skills

Full-stack

TypeScript

React

Node.js

Python

AI/ML systems

LLM

Cloud

Tools

Google Cloud

AWS

Job description

PRINCIPAL ENGINEER - FULLSTACK

COMPANY : Steven.com

REPORTING TO : VP of ENGINEERING

LOCATION: LONDON

ABOUT

Steven.com is building the operating system for the creator economy, forecast to pass a trillion dollars by the early 2030's. This industry is currently held back by fragmented tools and a lack of professional infrastructure. Steven.com is the unlock. We are the end-to-end Operating System designed to scale what is irreplaceably human.

We have built proprietary technology and obsessed teams to identify and scale the highest-potential creators across our core pillars:

• Creator Media: Amplifying reach, influence, and trust
• Creator Community: Transforming audiences into connected tribes
• Creator Products: Providing creators with the infrastructure to build and back aligned products and ventures
• Powered by Creator Tech & Intelligence: A proprietary data and technology suite that fuels smarter decisions and drives innovation across the entire flywheel.

Powering all of it is Steven.com's Innovation and Technology Organisation (ITO). We are building proprietary AI infrastructure, developing consumer and enterprise digital products, and creating the data and intelligence layer that drives smarter decisions across the business. Each pillar feeds the next. The result is a flywheel that compounds over time and bets on human creation at its core.

ROLE MISSION

The most senior individual contributor engineering seat at Steven.com. You set the technical bar for the whole engineering team, own architecture for the ITO's hardest and highest-stakes systems, and make the calls that don't have a committee to hide behind. Reporting to the CITO and partnering closely with the VP of Engineering & Applied AI, you own technical depth while they own execution and people. Founding team role. What you build in year one shapes the product for years.

KEY OUTCOMES

• Own the architecture of Steven.com's most complex systems, from design through production and long-term evolution
• Set the engineering standards, patterns, and abstractions the rest of the team builds on
• Architect the AI-native core of the product: LLM-powered workflows, intelligent pipelines, and agentic systems that don't exist yet
• Make the final call on high-stakes design decisions and catch systemic risk before it becomes debt or downtime
• Mentor senior and junior engineers, raise the bar through code review and architectural conversation
• Turn ambiguous product bets into concrete technical plans with clear tradeoffs, working directly with CITO, VP Eng, and Product

CORE COMPETENCIES

• Track record of designing and shipping complex, large-scale distributed systems in production, not just contributing to someone else's
• Deep full-stack proficiency: TypeScript, React, Node.js, Python, and Google Cloud/AWS
• Real experience architecting AI/ML systems, LLM applications, or intelligent pipelines at production scale
• Comfortable reasoning across levels of abstraction at once, from API design to infrastructure to product
• Sharp written communication, documentation a team can build from and an exec can understand

YOU'LL THRIVE HERE IF

• You see the whole system and never touch a component without understanding what it's connected to
• You reason from first principles, not analogy, and you'll challenge inherited architecture if the foundations are wrong
• You know when to be precise and when to be fast, and you make that call on purpose
• You have a real point of view on where AI infrastructure is heading
• You treat architectural decisions as close to permanent, so you document them properly and don't make them lightly
• You're intellectually honest: you push back early, surface problems fast, and change your mind when the evidence says to

IDEAL BACKGROUND

• Founding engineer, staff engineer, or technical lead at a startup or high-growth company
• CS or ML research background with production research experience
• Published research, open source work, conference talks, or other visible engineering community contribution
• We care less about titles, years, and pedigree, and more about the systems you can point to and defend end to end