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Senior Product Engineer

Kernel

Kernel

Software Engineering, Product
London, UK
GBP 120k-140k / year + Equity
Posted on Jun 6, 2025

TLDR: Join Kernel as an in‑office, backend‑savvy Senior Product Engineer to own and scale our AWS/Kubernetes stack and ship features fast, earning £120‑140 k + equity with visa sponsorship if needed, via a 5‑step hiring flow (intro chat → tech screen → 2‑hr take‑home → onsite deep‑dive → founder values interview) at a high‑growth, product‑focused startup. Context Video here

About Kernel

Kernel enables revenue teams to research companies as if they had unlimited time.

We’re growing extremely fast and working with many of the best revenue teams in the world like Remote.com, Navan, Zip, GoCardless, Cognism, and many more.

Previously, revenue teams relied on manual research to understand if a company had the problem they solved: Do job descriptions indicate doing what you automate? Who do they sell to? Is non-public financial data estimated to the right size? And what does this data tell me about their corporate card spend? Their travel expenses?

Our customers use Kernel to find this for every relevant company in the world to get complete overviews of ideal customers and pursue the right companies.

We’re a team of second-time founders and have raised $5mm+ from top VCs and revenue leaders at Open AI, Slack, Snowflake, and MongoDB.

Role - Sr. Engineer

You’re a well-versed “T-shaped” product engineer with a spike in backend engineering. You’ll be working with the product and engineering team on building the product in general, but will help support our existing infrastructure, ensuring we can scale in an efficient manner. You don’t have to be a DevOps wizard, but some experience working with AWS and Kubernetes would very helpful.

You’re adaptable, often taking initiative to identify and tackle tasks autonomously, and you enjoy making valuable contributions at pace. The lean nature of the team means you thrive in a low-structure environment, and having the ability to communicate clearly is very important.

You would ideally have the following:

  • 6+ years of software engineering experience

  • Experience working in an early stage start-up

  • A well-rounded product engineering toolkit

  • The ability to work independently and autonomously

  • The ability to operate in a small team with shifting priorities

  • Some experience working with Kubernetes

  • Experience working with large volumes of data

It would be a plus if you also have experience in:

  • LLM experience, such as building RAG-models and prompt engineering and familiarity with the main foundation models on the market

  • Some front-end experience

What you’ll be doing

Kernel provides customization at scale, which means we process millions of accounts, collect terabytes of data, and run tens of thousands of executions in parallel.

Your role will be to own our back-end infrastructure - everything from AWS to our workflow automations in n8n - helping us scale from $1M to $10M ARR.

We are still in early stages of building out our infrastructure which means you have the opportunity to play a key role in shaping what we build and how we build it.

More specifically you will be:

  • Working on ensuring a world-class, scalable back-end infrastructure.

  • Working daily with the team to move us toward our next goal

  • Rapidly shipping features to users and to our internal team

  • Continuously evaluating our code, infrastructure, and processes to see if they meet our needs, always looking for ways to improve

  • Automating our manual processes

  • Sharing feedback on roadmap direction and ideas on bets to place / potential solutions

❌ This role may not be for you if…

  • You need lots of structure

  • You’ll only ship pixel-perfect results

  • You need a fleshed-out spec to code

  • You’re heavily indexed on DevOps and have spent less time on product engineering

⚠️ This role is definitely not for you if ...

  • You prefer working remote or hybrid

  • You don't enjoy the intensity of an early-stage startup

  • You have side hustles or other projects

  • You want to manage a team

What we offer

We’ll do our very best to offer you a ride of a lifetime. It won’t be easy, but it will be thrilling.

  • Working directly with the founding team

  • A fast-paced ride in the early inning of a new technology wave

  • Weekly 1:1s to help you grow

  • Salary: £120 - 140k + equity

🛠️ Tech stack

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

  • Front-end: NextJS, Typescript, Tailwind

  • Workflow automation: n8n

❤️ Team

We are currently 17 people with 3 people in engineering and 1 Product Manager, specifically

🎫 Visas

We sponsor visas for exceptional candidates ✨

Stages

  • STAGE 1

    A 30 minute intro call with our Product Lead, Marcus (Hiring Manager). You’ll get an overview of Kernel, speak a bit about your own motivations, what you’re good at (and not so good!) plus an opportunity to ask questions.

  • STAGE 2

    A 30-minute technical screen with either Sam, Ele, or both. This is an opportunity for you to talk about products you're proud of having built and ask questions about Kernel's tech stack.

  • STAGE 3

    A take-home task where you’ll be asked to solve a real-world problem we’ve come across. You’ll spend a maximum of 2 hours on this challenge.

  • STAGE 4

    Come to our office for a 45-min technical interview. We’ll work through your take-home task and ask clarifying questions to understand your thinking.

  • FINAL STAGE

    Anders (Founder + CEO) conducts our Founder Interview. It’s a values-based discussion exploring your personal and professional values and how they align with ours.

  • Reference calls & Offer

    If you like us and we like you, it’ll be time to make you a job offer!

    We’ll email you an offer letter and simultaneously schedule a call to discuss the offer, package and answer any questions you might have.

    Reference calls: We will first have to complete at least 2 reference calls with your past managers and/or peers.