Senior Platform Engineer

Kernel; London; On-site; GBP 120,000 - 140,000; Full time

Job summary

A cutting-edge tech company in London is seeking a Senior Platform Engineer to manage their backend infrastructure and optimize databases. The ideal candidate will have over 6 years of experience with Postgres and AWS, focusing on high-volume data processes. Salary is competitive at £120-140k plus equity, and there is visa sponsorship if needed.

Benefits

Equity options

Bi-weekly 1:1s with management

Qualifications

• 6+ years of backend/infra engineering experience.
• Deep hands-on experience with Postgres.
• Strong background in AWS.
• Experience working with large-scale data pipelines.

Responsibilities

• Design and scale real-time write/read paths.
• Implement IaC across AWS/K8s.
• Experiment with schema options for wide-attribute entities.
• Hardening replication and data movement.

Skills

Postgres

AWS

Kubernetes

Infrastructure-as-Code

Tools

Terraform

Pulumi

Job description

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TL;DR

Join Kernel as an in-office, backend-savvy Senior Platform Engineer to own and scale our Postgres, AWS, and Kubernetes stack. You'll solve bottlenecks around high-volume writes, wide-attribute data models, replication, and real-time vs analytical data paths while bringing Infrastructure-as-Code (Terraform or Pulumi) practices to productionize and automate our infra.

This role pays £120-140k + equity, with visa sponsorship if needed, via a 4-step hiring flow: intro chat → 2-hr take-home → onsite deep-dive → founder values interview.

About Kernel

Kernel is building the source of truth for enterprise intelligence. RevOps teams at companies like Remote, Navan, Zip, GoCardless, and Cognism use Kernel to clean their CRMs, research companies, and target the right accounts with accuracy.

The challenge is massive: ~7B tokens processed per day, 1.8M+ agents running daily, and petabytes of messy data scraped, cleaned, and enriched. AI hallucinations are fine in chat, but not in RevOps - for us, the answer has to be correct. That means our engineering bar is extremely high, because some of the best revenue teams in the world depend on us.

We've raised $15M+ from top VCs and operators at OpenAI, Slack, Snowflake, and MongoDB.

Curious about the scale of the problems we're tackling? Check out The Kernel Log!

Role - Senior Platform Engineer

You're a backend-oriented engineer with strong experience in database infrastructure, IaC, and large-scale data systems. You'll work closely with our product and engineering teams to ensure Kernel's infra can handle:

• High-volume OLTP writes with immediate read-after-write consistency
• Thousands of dynamic attributes per entity (wide-table and indexing challenges)
• Separation of OLTP/OLAP paths with explicit freshness guarantees
• Replication/sharding at scale
• Efficient Kubernetes queueing and scheduling
• Cost optimisation and proactive capacity planning
• Infrastructure-as-Code to ensure reproducibility and automation
• Secure and observable infra that meets SOC2 standards

You'll thrive if you enjoy getting deep into DB internals, replication flows, and scaling infra for ML/data-heavy workloads - while still being comfortable in a fast-moving product environment.

You would ideally have the following

• 6+ years of backend / infra engineering experience
• Deep hands-on experience with Postgres (replication, partitioning, indexing, sharding) at scale
• Strong background in AWS (Aurora/RDS, S3, EKS/Kubernetes, networking, autoscaling, cost control)
• Hands-on experience with Infrastructure-as-Code (Terraform, Pulumi, or equivalent)
• Experience working with large-scale data pipelines, ideally in ML or analytics-heavy products
• Ability to operate autonomously and propose systemic fixes, not just patchwork

It would be a plus if you also have

• Experience with analytical stores (Redshift, Clickhouse, BigQuery) alongside OLTP systems
• Familiarity with search/retrieval infra (ElasticSearch, OpenSearch, vector DBs like Weaviate/Pinecone/FAISS)
• Observability & monitoring experience (Datadog, Prometheus, Grafana, CloudWatch)
• Experience in cost modelling, queue scheduling, or infra observability
• Exposure to multi-cloud (AWS + GCP) environments
• Hands-on work with event streaming (Kafka, Kinesis, MSK)
• Some exposure to LLM infra / retrieval systems (RAG, vector DBs, hybrid serving)

What you'll be doing

Kernel processes millions of accounts, petabytes of data, and millions of parallel agent executions every day.

Your role will be to own our infra scaling journey, from Postgres schema design to AWS autoscaling to replication flows, making sure our systems stay fast, reliable, and cost-efficient as we grow.

Specifically, you'll be:

• Designing and scaling real-time write/read paths that balance OLTP and OLAP needs
• Implementing IaC (Terraform or Pulumi) across AWS/K8s for reproducible infra and faster iteration
• Experimenting with schema options for wide-attribute entities and indexing strategies
• Hardening replication and data movement between Postgres and analytical stores
• Consolidating and right-sizing K8s queues, with scheduling/guardrails for heavy jobs
• Driving cost efficiency through infra modelling, observability, and autoscaling
• Producing key artifacts: problem registers, replication diagrams, freshness matrices, slow-query baselines

This role may not be for you if...

• You want only pure product feature work - this role leans deep into infra
  You need rigid structure and long-term roadmaps - many problems are still open research tracks
• You're heavily indexed on DevOps tooling but lack database/infra depth

This role is definitely not for you if ...

• You prefer remote/hybrid work
• You don't enjoy the intensity of early-stage startup infra firefighting
• You want to manage, not build

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.

• Work directly with the founding team
• Shape infra strategy at the ground floor of a fast-growing ML-driven product
• Bi-weekly 1:1s to help you grow
• Salary: £120 - 140k + equity

Tech stack

• Core DB: Postgres (JSONB, partitioning, pglogical, replication strategies)
• Analytics: Redshift, Clickhouse (evaluated for OLTP/OLAP split)
• Infra: AWS, Kubernetes, Terraform/Pulumi for IaC, n8n for workflow automation
• Backend: NodeJS, Typescript
• Front-end: NextJS, Typescript, Tailwind

Team

• Fara Ashiru, Head of Engineering
• Sam Houghton, Founding Engineer
• Eleanor Leung, Sr Engineer
• Tom Ankers, Sr Engineer
• Willis Chou, Sr Engineer
• David Saltares, Sr Engineer
• Stefan Sabev, Head of Product

Visas

We sponsor visas for exceptional candidates

Interview Process

STAGE 1

A 45 minute intro call with Fara (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 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) & Macus conduct our Founders interview. It's a values-based discussion exploring your personal and professional values and how they align with ours.If you like us and we like you, it'll be time to make you a job offer after reference checks!