Senior Platform Engineer ( Backstage / Internal Developer Platform)

Project Description:

We run and evolve an Internal Developer Platform (IDP) built on Backstage for one of our customers. The platform is live and used daily by their engineering organisation, and we are responsible for its support, stability and further development.

We are looking for someone who has genuinely operated and extended Backstage in production to take technical ownership of the platform, unblock day-to-day support, and bring the rest of the team up to speed.

This is a hands-on engineering role with a strong knowledge-transfer component, working directly with the customer's platform and developer-experience stakeholders.

Responsibilities:

Take technical ownership of the customer's Backstage instance: architecture, stability, performance and upgrade path
Handle escalated support issues — catalog ingestion failures, broken plugins, auth problems, TechDocs build errors, scaffolder task failures — and turn recurring incidents into permanent fixes
Design and build custom plugins (React/TypeScript frontend, Node.js backend) and integrations with the customer's toolchain: source control, CI/CD, Kubernetes, observability, ticketing, cloud providers
Model and maintain the Software Catalog: entity model, ownership, relations, custom processors and entity providers, catalog data quality
Build and maintain Software Templates (Scaffolder) and custom scaffolder actions for golden-path onboarding
Configure and extend authentication, authorization and the permissions framework, including SSO and RBAC aligned with the customer's identity provider
Own the Backstage upgrade process — Backstage ships frequent releases, and we need someone who can keep us current without breaking the customer's platform, including migration to the new backend and frontend systems
Own deployment and operations of the platform: containerisation, Kubernetes/Helm, CI/CD pipelines, PostgreSQL, monitoring, alerting and backups
Mentor the two existing engineers: pairing, code review, internal documentation and runbooks, with the explicit goal that the team can support the platform independently
Work with the customer to shape the platform roadmap and translate developer-experience goals into concrete plugins and workflows

Mandatory Skills Description:

5+ years of experience
Hands-on production experience with Backstage — building, customizing, deploying and supporting it, not just evaluating or demoing it
Strong TypeScript, plus practical React (frontend plugins) and Node.js/Express (backend plugins)
Demonstrated experience developing custom Backstage plugins and integrations, and extending the Software Catalog and Scaffolder
Solid DevOps foundation: Docker, Kubernetes, Helm, CI/CD, Infrastructure as Code (Terraform or equivalent), at least one major cloud (AWS / Azure / GCP)
Experience with authentication and authorization patterns: OIDC/OAuth2, SSO providers, RBAC
Comfortable operating a platform under a support model — triage, prioritisation, root-cause analysis, SLAs
Ability to mentor peers and document what you build; you enjoy making other engineers more effective
Customer-facing communication skills and professional English

Nice-to-Have Skills Description:

Contributions to the upstream Backstage project or its plugin ecosystem
Experience migrating a Backstage instance to the new backend system and/or the new frontend system
Experience with managed or commercial Backstage offerings, or with alternative IDP products (Port, Cortex, Humanitec) for comparison and advisory conversations
TechDocs at scale, GraphQL, OpenAPI-driven integrations, PostgreSQL performance tuning
Platform engineering / developer-experience background: golden paths, self-service, scorecards, DORA metrics

Languages:

• English: C1 Advanced