Software Engineer (Principal level)

🔒 Confidential Employer
Posted 22 March 2026
LOCATION
London
TYPE
Full-time
LEVEL
Mid-Senior level
CATEGORY
Technology
This employer holds a UK Home Office sponsor license — sponsorship for this specific role is at the employer’s discretion

SKILLS

Backend SaaS Python React AI Engineering Server Side Enterprise-grade

FULL DESCRIPTION

Software Engineer (Principal level)

[Employer hidden — view at passion-project.co.uk] is seeking a Principal Software Engineer to focus on backend issues, drive projects across multiple teams, and contribute to the long-term direction of engineering. The role requires at least ten years of experience, leadership skills, and expertise in building enterprise-grade SaaS products, with a focus on AI-powered video generation.

About the role

- You will focus on friction points around primarily backend issues for all teams in Engineering (90 Engineers). How should we do inter-service testing? Some teams are using monorepo, others aren’t. How can we bring overall stability up? Generally steering BE in the right direction. In the near future, standardising things across all of Engineering and bringing R&D teams (another 40 Engineers and Researchers) closer.

- You will have ownership of projects that span quarters, requiring you to have the ability to break a problem down into small steps that can be delivered and validated iteratively.

- You will evaluate your own work, leveraging our data pipeline and frameworks that we have established to understand the impact your features have on our commercial objectives and pivoting where necessary.

- You will consider the long-term direction of Engineering, making sure that we are developing the engineering capabilities that will allow us to stay ahead of the challenges we are likely to encounter in 12-18 months' time.

- You will work end-to-end, from our client application written in React to our monolithic backend written in Python, and lead projects that span across multiple teams.

What we're looking for:

  • At least ten (10) years of experience as a software engineer, at least 2 at the Senior Staff/Principal level (L7+).
  • Previous leadership experience in driving projects across multiple teams (50+ Engineers).
  • Experience in a high-performing engineering Org that is operating at scale. This could come from a scale-up environment or a more established organization recognised for building and shipping with a great engineering culture.
  • An ability to work across the stack, with deep knowledge on server side and all things back end related.
  • Relevant engineering experience for a team building an enterprise-grade SaaS product. Extra points for delivering AI-powered video generation product, billing systems, experimentation platforms, video delivery systems, online editors, real-time collaboration and so on.
  • Strong alignment with commercial success.

Why join us?

We’re living the golden age of AI. The next decade will yield the next iconic companies, and we dare to say we have what it takes to become one. Here’s why,

Our culture

At [Employer hidden] we’re passionate about building, not talking, planning or politicising. We strive to hire the smartest, kindest and most unrelenting people and let them do their best work without distractions. Our work principles serve as our charter for how we make decisions, give feedback and structure our work to empower everyone to go as fast as possible. You can find out more about these principles here.

Serving 50,000+ customers (and 50% of the Fortune 500)

We’re trusted by leading brands such as Heineken, Zoom, Xerox, McDonald’s and more. Read stories from happy customers and what 1,200+ people say on G2.

Proprietary AI technology

Since 2017, we’ve been pioneering advancements in Generative AI. Our AI technology is built in-house, by a team of world-class AI researchers and engineers. Learn more about our AI Research Lab and the team behind.

AI Safety, Ethics and Security

AI safety, ethics, and security are fundamental to our mission. While the full scope of Artificial Intelligence's impact on our society is still unfolding, our position is clear: People first. Always.  Learn more about our commitments to AI Ethics, Safety & Security.

Other important info:

- This is a remote role from an EU country, UK or Switzerland.

- The salary starts at EUR/GBP/CHF 200.000 base + stock option plan.

- This is full-time employment only - no contractors possible - usually through OysterHR.

- Everyone at [Employer hidden] gets 25 days of leave + local holidays (no extra paid or unpaid leave possible).

- We only sponsor VISA if you are in the UK/EU country already and need support - we do not relocate people.

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