Engineering Project Manager - Full Time in London

Picnic’s mission is to drive a higher-quality ad-funded internet. Today, a large proportion of digital advertising is ineffective, intrusive, and poorly optimised. Picnic builds technology that helps brands make better decisions about where and how their advertising is shown - improving outcomes for users, advertisers and publishers.

We’re a fast-growing, founder-led startup. Over the last couple of years, we’ve built a strong platform foundation and developed clear conviction around our product direction. We’re now entering a new stage where architectural coherence, reliability and scale matter as much as innovation.

To support this next phase, we’re looking for a Principal Engineer to take ownership of system design, platform evolution and technical quality across the business.

As Principal Engineer, you’ll report to the Chief Product & Technology Officer and act as the technical centre of gravity for Picnic’s systems and architecture - ensuring we build scalable, cost-efficient, production-grade infrastructure as the platform grows. This is a senior individual contributor role first and foremost - focused on building strong systems, raising engineering standards and increasing overall engineering leverage.

While this is not primarily a people management position, there is opportunity to take on mentorship and leadership responsibilities within the engineering team.

• Act as architectural steward of the platform, ensuring scalability, reliability, performance, and cost efficiency as complexity increases.
• Design and evolve backend systems, data pipelines, real-time services, and APIs to support both internal capabilities and external customers.
• Introduce clear engineering principles and patterns to reduce duplication and architectural drift across workstreams.
• Strengthen AWS architecture and cloud cost efficiency through thoughtful service design, right-sizing, and operational discipline.
• Embed AI-native development workflows across the team - using LLMs and agents effectively for code generation, testing, refactoring, documentation, and experimentation.
• Be deeply experienced in cloud architecture, particularly within AWS.
• Have worked across product engineering, infrastructure, and data systems.
• Be confident designing systems that balance short-term delivery with long-term maintainability.
• Be comfortable integrating AI tools and agent workflows into engineering practice.
• Demonstrate strong judgement around trade-offs, technical debt, and operational risk.
• Experience in advertising technology is a bonus!

You’ll be joining Picnic at a pivotal moment, where strong architectural decisions and engineering leverage can materially shape the trajectory and value of the business. Ideas move quickly from concept to production - we value momentum, quality and impact. You’ll help shape an AI-native engineering culture in a small, ambitious team.

We’re proud to have been recognised by Culture100 and Flexa as one of the best and most flexible small businesses to work for. Flexible, hybrid working setup (with regular time in the office throughout the week so you will live in or around London) ~33 days holiday (inclusive of Bank Holidays).