Senior Full Stack Engineer

Kernel; City Of London; On-site; GBP 120,000 - 200,000; Full time

Job summary

A tech startup in London is seeking a full stack engineer to own and scale their back-end infrastructure. You will play a crucial role in shaping the infrastructure as the company aims to grow from $1M to $10M ARR. The ideal candidate has over 6 years of software engineering experience, enjoys a fast-paced environment, and has skills in AWS, NodeJS, and Kubernetes. A competitive salary of £120,000 - £200,000 plus equity is offered, along with generous perks.

Benefits

Equity

24 days holiday plus bank holidays

2 weeks work-from-anywhere

Pension plan

Top-spec equipment

Free dinner at the office

Team events and dinners

Qualifications

• 6+ years of software engineering experience.
• Experience in an early-stage startup or small, fast-moving team.
• A well-rounded engineering toolkit and strong backend depth.

Responsibilities

• Own and scale Kernel's back-end infrastructure.
• Design systems processing millions of accounts and terabytes of data.
• Build reliable, scalable data pipelines and services.

Skills

Software engineering

Backend engineering

Data management

Initiative

Clear communication

Working in fast-paced environments

Tools

AWS

Kubernetes

NodeJS

Postgres

n8n

Job description

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About Kernel

Kernel gives enterprise RevOps teams confidence in their CRM data.

We've raised a $14M Series A from top VCs and operators at Plaid, OpenAI, Slack and others to build the AI-native alternative to Dun & Bradstreet's entity and hierarchy data.

RevOps teams at Gong, Navan, Zip, Remote and GoCardless use Kernel to clean, enrich and complete their CRM data at enterprise scale, eliminating duplicates, fixing hierarchies and restoring trust in the foundation that powers forecasting, territory planning and AI initiatives.

Our platform combines entity-level intelligence with mass-action tooling to give RevOps teams the data quality and control needed to plan confidently and deploy AI successfully.

The Role

You are a T-shaped full stack engineer with a spike in backend engineering. You will work with product and engineering on the product overall and support our infrastructure so we can scale efficiently. You do not need to be a DevOps wizard, but experience with AWS and Kubernetes is helpful.

You are adaptable, take initiative and enjoy contributing at pace. The team is lean, the environment is low-structure and clear communication matters. You will own our back-end infrastructure from AWS to our workflow automations in n8n and help us scale from $1 M to $10 M ARR. We are still early in building our infrastructure, so you will play a key role in shaping what we build and how we build it.

What You’ll Be Doing

• Owning and scaling Kernel's back-end infrastructure (AWS, NodeJS, Postgres, n8n)
• Designing systems that process millions of accounts, terabytes of data and thousands of parallel executions
• Building reliable, scalable data pipelines and services for enterprise customers
• Rapidly shipping features to users and to our internal team
• Continuously evaluating code, infrastructure and processes to find improvements
• Automating manual processes to increase speed and reliability
• Sharing feedback on roadmap direction and ideas on bets to place and potential solutions

More specifically you will be:

• Ensuring a world-class, scalable back-end infrastructure
• Working daily with the team to move us toward our next goal
• Implementing mass-action workflows that clean, enrich and complete CRM data
• Establishing robust monitoring, observability and reliability practices
• Partnering with product and solutions engineering to translate business logic into safe mass actions in customer CRMs

What You Bring

• 6+ years of software engineering experience
• Experience in an early-stage startup or small, fast-moving team
• A well-rounded engineering toolkit and strong backend depth
• Ability to work independently and autonomously with clear communication
• Ability to operate in a small team with shifting priorities
• Some experience with Kubernetes
• Experience working with large volumes of data

It is a plus if you also have:

• LLM experience such as building RAG models, prompt engineering and familiarity with major foundation models
• Some front-end experience

This role may not be for you if you:

• Need lots of structure
• Will only ship pixel-perfect results before releasing
• Need a fully fleshed-out spec to code
• Are heavily indexed on DevOps and have spent less time on software engineering

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)
• Do not enjoy the intensity of an early-stage startup
• Have side hustles or other projects
• Want to manage a team

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 4 engineers and 1 Product Manager, including:

• Fara Ashiru, Head of Engineering
• 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 Sandi. 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.