Principal Engineer

Oliver Bernard; Greater London; Hybrid; GBP 230,000 - 311,000; Full time

Job summary

Oliver Bernard in London is seeking a Principal Engineer for a fast-growing, Series A scale-up. This is a hands-on IC role focused on scalable backend systems and operating at scale. You will work directly with the Head of Engineering and CTO, contributing immediately to high-impact engineering initiatives.

The ideal candidate has taken companies from Series A through Series C, with a proven track record of diagnosing complex problems and delivering scale, plus real hands-on Python experience.

Qualifications

• Computer science background required.
• Hands-on Python experience.
• Track record of scaling from Series A to Series C.

Responsibilities

• Own and scale backend systems to handle growth.
• Diagnose and fix hard systems problems under pressure.
• Collaborate with Head of Engineering and CTO to unlock growth.

Skills

Python

Education

Computer science background

Job description

Principal Engineer - Series A Scale Up - Up to £270,000

I'm currently looking for a Principal Engineer to join a high-growth, YC-backed AI startup based in London.

It's a hands-on IC role focused primarily on scalable backend systems and genuinely at scale.

You'll be working directly with the Head of Engineering and CTO/Co-Founder — your impact will be visible and felt from day one. They're looking for someone who has taken companies from Series A through to Series C on multiple occasions; someone who has walked into complex, high-pressure environments, diagnosed the problems, fixed them, and unlocked the next phase of growth. This is about scaling products, not just teams.

Working Arrangements: 3 days per week in Central London office

Why it might interest you

• YC-backed and scaling fast, adding 10 heads to engineering over the next few months
• Real AI in production (not just R&D)
• Smart, driven team of builders — ex-Meta, Spotify, MIT, and high-growth startups
• Large Series A investment already secured + up to 9 million in ARR

Ideal profile

• – Computer science background
• – Strong, demonstrable signal of impact in previous roles
• – Experience taking companies from Series A through to Series C
• – A track record of fixing hard systems problems that unlocked scale
• – Have real hands-on Python experience

Principal Engineer - Series A Scale Up - Up to £270,000