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Senior Product Engineer

Kernel

Kernel

Software Engineering, Product
London, UK
GBP 120k-200k / year + Equity
Posted on Jan 19, 2026

Location

London

Employment Type

Full time

Location Type

Hybrid

Department

Engineering

Compensation

  • £120K – £200K • Offers Equity

About Kernel

Kernel provides enterprise RevOps teams with AI-powered company data for their CRMs. We raised $14M in Series A funding from top VCs and operators at Plaid, OpenAI, and Slack to build an AI-native alternative to Dun & Bradstreet's entity and hierarchy data.

RevOps teams at Navan, Gong, Mistral, and AlphaSense use Kernel to run their organizations.

At Kernel, we process 7B+ tokens a day and run 1.8M+ agents daily, all on an architecture that’s intentionally simple: one database, one queue. It’s minimalism built for massive scale (For reference, Wikipedia has 2.3B tokens in the English wikipedia). Our queue processes a daily volume on par with the entire Visa network’s transactions (~365M/day). All of which has been built by a small but mighty team of engineers.

The Role

You are a T-shaped product engineer with a spike in backend engineering. You will work closely with the product and engineering team to build user-facing features, ship at pace, and support the existing infrastructure as we scale. You do not need to be a DevOps expert, but familiarity with AWS and Kubernetes is valuable.

You take initiative, adapt quickly, and communicate clearly. The team is small and fast-moving, so you’ll be expected to make decisions and ship code autonomously. You will help us scale from $1M to $10M ARR, owning projects end-to-end—from ideation to deployment—while helping shape how we build products and infrastructure at Kernel.

What You’ll Be Doing

  • Designing and developing product features that directly impact user workflows

  • Collaborating with design, product, and other engineers to deliver exceptional user experiences

  • Writing and maintaining clean, reliable, and scalable code across the stack

  • Helping ensure performance and reliability for large-scale data operations

  • Automating workflows to improve developer velocity and reduce manual work

  • Supporting integrations with CRMs and third-party APIs

  • Participating in roadmap discussions and contributing technical insights

What You Bring

  • 6+ years of software or product engineering experience

  • Strong experience building and scaling production systems

  • Comfort with backend engineering (NodeJS, Postgres, TypeScript)

  • Strong understanding of LLM application development patterns (RAG, prompt engineering, consistency testing) - either through production experience or demonstrated personal projects. If you're new to LLMs but have shipped complex production systems in other domains and are comfortable rapidly learning new technologies, we'd still love to hear from you.

  • Ability to operate autonomously in a small, high-velocity team

  • Excellent communication and collaboration skills

  • Some experience with Kubernetes or distributed systems

It is a plus if you also have:

  • Experience working on AI-driven or data-heavy products

  • Frontend experience (NextJS, React, TypeScript)

  • Understanding of CRM data models or workflow automation

⚠️ This role may not be for you if you:

  • Need lots of structure or long-term roadmaps

  • Prefer perfect specs before building

  • Focus narrowly on backend or frontend only

This role is definitely not for you if you:

  • Prefer fully remote work (this role requires at least 3 days a week in the office)

  • Don’t enjoy the pace of early-stage startups

  • Want to manage a team rather than build

What We Offer

We will do our best to offer you a ride of a lifetime. It will not be easy, but it will be thrilling.

  • 💰 Salary: £120,000 – £200,000 + equity

  • 🗓️ 24 days holiday per year + bank holidays

  • ✈️ 2 weeks work-from-anywhere

  • 💼 Pension plan

  • 💻 Top-spec equipment and central London office

  • 🍽️ Free dinner at the office

  • 🎉 Team events and dinners

  • 🚀 Work directly with the founders to scale the systems that power enterprise AI

🛠️ Tech Stack

  • Back-end (AWS): NodeJS, TypeScript, Postgres

  • Front-end: NextJS, TypeScript, Tailwind

  • Workflow automation: n8n

❤️ Team

We are around 30 people with 7 engineers and 1 Product Manager, including:

  • Sam Houghton, Founding Engineer

  • Eleanor Leung, Senior Engineer

  • David Saltares, Senior Engineer

  • Stefan Sabev, Head of Product

  • Tom Ankers, Senior Engineer

  • Willis Chou, Senior Engineer

🎫 Visas & Relocation

We sponsor visas for exceptional candidates and provide relocation support for those moving to London.

Interview Process

Stage 1 – 30-minute intro call with a key member of our hiring team. You will get an overview of Kernel and discuss your motivations and strengths.

Stage 2 – Take-home task (≤ 4 hours) solving a real Kernel problem.

Stage 3 – 90-minute technical interview in our London office to review your solution and understand your thinking.

Final Stage – Founders interview with Anders (CEO) and Marcus to explore values alignment.

If there is mutual fit, we move to references and offer.

Compensation Range: £120K - £200K