Backend Engineer

Tantilium; Greater London; Hybrid; GBP 90,000 - 130,000; Full time

Job summary

Tantilium is seeking a backend engineer to build Go services powering Tantilium Cloud Runner. You will craft APIs, controllers and event pipelines that provision clusters, ship applications and keep them healthy.

We use Chi for HTTP, Bun on PostgreSQL, RabbitMQ for events, and Kubernetes via client-go. You’ll design new services, improve existing ones, and help keep the system understandable as it grows.

Qualifications

• Production Go backend experience.
• Kubernetes knowledge and deployments.
• REST API design experience.
• Relational DB design and migrations.
• Distributed systems concepts (idempotency, retries, timeouts, eventual consistency).
• Observability with Prometheus/Grafana.

Responsibilities

• Design, build and run backend services and APIs in Go, from design to production.
• Write Kubernetes controllers and integrations that handle slow or misconfigured clusters.
• Model data in PostgreSQL and design event flows over RabbitMQ with retry semantics.
• Instrument systems with metrics, logs and traces for easy troubleshooting.
• Participate in on-call rotations and contribute to blameless incident reviews.
• Review code, write design docs and help set engineering patterns.

Skills

Go backend development

REST API design

Observability

Distributed systems

Education

Bachelor's degree in CS or related

Tools

Kubernetes

PostgreSQL

RabbitMQ

Flux

Terraform

Git

Argo CD

client-go

Job description

Build the Go services behind Tantilium Cloud Runner: the APIs, controllers and event pipelines that provision clusters, ship applications and keep them healthy.

Behind the dashboard sits a few dozen Go services. Some provision clusters on AWS and GCP. Some reconcile applications into tenant vClusters through Git and Flux. Others collect metrics, open incidents, and run AI agents that can investigate a problem and, with approval, fix it.

We follow a ports-and-adapters layout across every service, use Chi for HTTP, Bun on PostgreSQL for storage and RabbitMQ for events, and talk to Kubernetes through client-go. You'll design new services, improve the ones we have, and help make sure the whole system stays understandable as it grows.

Responsibilities

• Design, build and run backend services and APIs in Go, from first design doc to production
• Write Kubernetes controllers and integrations that behave well when clusters are slow, flaky or misconfigured
• Model data in PostgreSQL and design event flows over RabbitMQ that can survive retries and partial failures
• Instrument what you build with metrics, logs and traces so problems are easy to spot and diagnose
• Take part in a fair on-call rotation, and help write the blameless reviews that follow an incident
• Review code, write clear design docs and help set the patterns other engineers follow

Requirements

• Solid experience building backend services in production, ideally in Go. If your background is Java or Kotlin and you're keen to work in Go, we'd still like to talk
• Good working knowledge of Kubernetes: deployments, services, RBAC and how workloads behave when things go wrong
• Experience designing REST APIs that other teams depend on
• Comfort with relational databases, including schema design, migrations and query performance
• An understanding of distributed systems trade-offs such as idempotency, retries, timeouts and eventual consistency
• Experience running what you build, with observability tools like Prometheus and Grafana

Nice to have

• You've written a Kubernetes operator or worked with controller-runtime or client-go
• Experience with GitOps tools like Flux or Argo CD
• Infrastructure as code with Terraform
• Experience with message brokers such as RabbitMQ, Kafka or NATS
• Interest in LLM-based tooling and how to make it safe in production