Platform engineering became a formal discipline in 2021. What it really means is building internal infrastructure that application teams can use as self-service, so they spend less time on ops and more time shipping.
What platform engineering is
A platform engineering team builds and operates internal tools and infrastructure that other engineering teams use to deliver software. The output is an Internal Developer Platform (IDP): the golden paths, templates, deployment pipelines, observability defaults, and service catalogue that product teams consume. The platform team treats developers as customers.
Backstage as the service catalogue standard
Spotify's Backstage, open-sourced in 2020, became the de-facto standard for the developer portal component of an IDP in 2021. Backstage provides a service catalogue, documentation, templates for scaffolding new services, and a plugin ecosystem for integrating CI/CD, cloud resources, and observability tools. The plugin ecosystem grew rapidly through 2021 and the CNCF donation broadened adoption.
The team topologies influence
Matthew Skelton and Manuel Pais's Team Topologies framework (published 2019) became the architectural framework for platform teams in 2021. The Stream-aligned team / Platform team / Enabling team / Complicated-subsystem team model provided a shared vocabulary for organisational design. 'Platform team' as a job description category grew measurably in 2021 job postings.
Measuring platform success
Platform teams fail when they build tools for their own satisfaction rather than developer productivity. The measurement framework that works: developer satisfaction surveys (quarterly), time-to-production for a new service, number of teams consuming each platform capability, and reduction in support burden per team over time. The platform is successful when developers use it voluntarily because it makes their work faster and easier.