A core feature of Backstage is the extensibility via plugins. The Backstage
repository is open for contributions of plugins. Even most of the core features
are implemented as plugins. A plugin consists of one or multiple packages in the
plugins/ directory. Up till now, we have a simple conventions for naming
plugin packages: Plugins are named
x, with the option of having a related
backend plugin called
x is the plugin name, like
techdocs). There is a need for sharing code between the frontend and
backend of a plugin, between backend plugins, or components and hooks between
different frontend plugins
This results in emerging plugin packages with shared code, like
There is a common phrase in software development: Naming things is hard
To keep the contributed plugins consistent, this Architecture Decision Record provides rules for naming plugin packages.
We will place all plugin related code in the
plugins/ directory. The
packages/ directory is reserved for core package of Backstage.
We follow this structure for plugin packages (where
x is the plugin name, for
x: Contains the main frontend code of the plugin.
x-module-<name>: Contains optional modules related to the frontend plugin package.
x-backend: Contains the main backend code of the plugin.
x-backend-module-<name>: Contains optional modules related to the backend plugin package.
x-react: Contains shared widgets, hooks and similar that both the plugin itself (
x) and third-party frontend plugins can depend on.
x-node: Contains utilities for backends that both the plugin backend itself (
x-backend) and third-party backend plugins can depend on.
x-common: An isomorphic package with platform agnostic models, clients, and utilities that all packages above or any third-party plugin package can depend on.
We prefix the package names with
This structure is based on a suggestion in issue #3655.
We will actively migrate existing packages that are part of a plugin to the
plugins/ folder. This affects packages like:
packages/techdocs-commonwhich should be moved to
packages/catalog-clientwhich will be part of a future
- While the new location of
plugins/catalog-commonwe might want to do an exception here, as it's a very central package.
We will actively migrate optional features of backend plugins into separate
x-backend-module-<name> packages, for example the more specialized processors
in the catalog backend.
The limited set of rules might not be sufficient in the future. If additional packages are required, we will revisit this decision and extend the pattern.
If possible, we will add tools, such as lint rules, to help enforce the package names and dependencies between them or CLI commands to generate these packages.
The distinction between core packages and plugins helps us to setup
in the repository. We can set the code owners for the
packages/ folder to the
core team and create additional rules (like
plugins/x*) for plugin