# @backstage/plugin-catalog-backend > The Backstage backend plugin that provides the Backstage catalog Latest version **4.0.0** (published 2026-09-15) · Apache-2.0 license · 0 weekly downloads ## Install ```sh npm install @backstage/plugin-catalog-backend pnpm add @backstage/plugin-catalog-backend yarn add @backstage/plugin-catalog-backend bun add @backstage/plugin-catalog-backend ``` ## Health **Score 75/100 (B)** — status: active. Positive: has types; esm support; no vulnerabilities; recently updated; high maintenance score; high quality score; popular repo. Warnings: low downloads. ## Facts | | | |---|---| | Version | 4.0.0 | | Published | 2026-09-15 | | First published | 2020-06-17 | | Weekly downloads | 0 | | License | Apache-2.0 | | TypeScript types | bundled | | Module format | ESM + CommonJS | | Dependencies | 33 | | Unpacked size | 1.8 MB | | Known vulnerabilities | 0 | | Install scripts | no | | GitHub stars | 34409 | | Maintainers | patriko, freben, marcuseide | | Keywords | backstage | ## Links - npm: https://www.npmjs.com/package/@backstage/plugin-catalog-backend - Repository: https://github.com/backstage/backstage - Homepage: https://backstage.io - npm.io page: https://npm.io/package/@backstage/plugin-catalog-backend ## Dependencies (33) - [yn](https://npm.io/package/yn.md) ^4.0.0 - [ajv](https://npm.io/package/ajv.md) ^8.10.0 - [zod](https://npm.io/package/zod.md) ^3.25.76 || ^4.0.0 - [glob](https://npm.io/package/glob.md) ^13.0.0 - [knex](https://npm.io/package/knex.md) ^3.0.0 - [yaml](https://npm.io/package/yaml.md) ^2.0.0 - [luxon](https://npm.io/package/luxon.md) ^3.0.0 - [lodash](https://npm.io/package/lodash.md) ^4.17.21 - [core-js](https://npm.io/package/core-js.md) ^3.6.5 - [express](https://npm.io/package/express.md) ^4.22.0 - [p-limit](https://npm.io/package/p-limit.md) ^3.0.2 - [fs-extra](https://npm.io/package/fs-extra.md) ^11.2.0 - [minimatch](https://npm.io/package/minimatch.md) ^10.2.1 - [ajv-errors](https://npm.io/package/ajv-errors.md) ^3.0.0 - [prom-client](https://npm.io/package/prom-client.md) ^15.0.0 - [git-url-parse](https://npm.io/package/git-url-parse.md) ^15.0.0 - [@backstage/types](https://npm.io/package/@backstage/types.md) ^1.2.2 - [@backstage/config](https://npm.io/package/@backstage/config.md) ^1.3.9 - [@backstage/errors](https://npm.io/package/@backstage/errors.md) ^1.3.1 - [@opentelemetry/api](https://npm.io/package/@opentelemetry/api.md) ^1.9.0 - [zod-validation-error](https://npm.io/package/zod-validation-error.md) ^5.0.0 - [@backstage/integration](https://npm.io/package/@backstage/integration.md) ^2.1.2 - [@backstage/catalog-model](https://npm.io/package/@backstage/catalog-model.md) ^1.10.1 - [@backstage/catalog-client](https://npm.io/package/@backstage/catalog-client.md) ^1.16.2 - [fast-json-stable-stringify](https://npm.io/package/fast-json-stable-stringify.md) ^2.1.0 - [@backstage/filter-predicates](https://npm.io/package/@backstage/filter-predicates.md) ^0.1.5 - [@backstage/backend-plugin-api](https://npm.io/package/@backstage/backend-plugin-api.md) ^1.10.1 - [@backstage/plugin-events-node](https://npm.io/package/@backstage/plugin-events-node.md) ^0.4.26 - [@backstage/plugin-catalog-node](https://npm.io/package/@backstage/plugin-catalog-node.md) ^2.2.5 - [@backstage/backend-openapi-utils](https://npm.io/package/@backstage/backend-openapi-utils.md) ^0.7.2 - [@backstage/plugin-catalog-common](https://npm.io/package/@backstage/plugin-catalog-common.md) ^1.2.0 - [@backstage/plugin-permission-node](https://npm.io/package/@backstage/plugin-permission-node.md) ^0.11.4 - [@backstage/plugin-permission-common](https://npm.io/package/@backstage/plugin-permission-common.md) ^0.9.11 ## Recent versions - 4.0.0 (latest) — 2026-09-15 - 0.0.0-nightly-20260918023200 (nightly) — 2026-09-18 - 4.0.0-next.1 (next) — 2026-09-08 - 0.0.0-nightly-20260917023108 — 2026-09-17 - 0.0.0-nightly-20260916022921 — 2026-09-16 - 0.0.0-nightly-20260909022715 — 2026-09-09 - 0.0.0-nightly-20260904022803 — 2026-09-04 - 0.0.0-nightly-20260902024315 — 2026-09-02 - 3.9.2-next.0 — 2026-09-01 - 3.5.1 — 2026-08-29 - 3.6.2 — 2026-08-29 - 3.7.2 — 2026-08-29 - 0.0.0-nightly-20260829022506 — 2026-08-29 - 3.8.2 — 2026-08-28 - 3.9.1 — 2026-08-28 - … 2082 more at https://npm.io/package/@backstage/plugin-catalog-backend/versions ## README # Catalog Backend This is the backend for the default Backstage [software catalog](http://backstage.io/docs/features/software-catalog/). This provides an API for consumers such as the frontend [catalog plugin](https://github.com/backstage/backstage/tree/master/plugins/catalog). It comes with a builtin database-backed implementation of the catalog that can store and serve your catalog for you. It can also act as a bridge to your existing catalog solutions, either ingesting data to store in the database, or by effectively proxying calls to an external catalog service. ## Installation This `@backstage/plugin-catalog-backend` package comes installed by default in any Backstage application created with `npx @backstage/create-app`, so installation is not usually required. To check if you already have the package, look under `packages/backend/package.json`, in the `dependencies` block, for `@backstage/plugin-catalog-backend`. The instructions below walk through restoring the plugin, if you previously removed it. ### Install the package ```bash # From your Backstage root directory yarn --cwd packages/backend add @backstage/plugin-catalog-backend ``` Then add the plugin to your backend, typically in `packages/backend/src/index.ts`: ```ts const backend = createBackend(); // ... backend.add(import('@backstage/plugin-catalog-backend')); ``` #### Old backend system In the old backend system there's a bit more wiring required. You'll need to create a file called `packages/backend/src/plugins/catalog.ts` with contents matching [catalog.ts in the create-app template](https://github.com/backstage/backstage/blob/ad9314d3a7e0405719ba93badf96e97adde8ef83/packages/create-app/templates/default-app/packages/backend/src/plugins/catalog.ts). With the `catalog.ts` router setup in place, add the router to `packages/backend/src/index.ts`: ```diff +import catalog from './plugins/catalog'; async function main() { ... const createEnv = makeCreateEnv(config); + const catalogEnv = useHotMemoize(module, () => createEnv('catalog')); const scaffolderEnv = useHotMemoize(module, () => createEnv('scaffolder')); const apiRouter = Router(); + apiRouter.use('/catalog', await catalog(catalogEnv)); ... apiRouter.use(notFoundHandler()); ``` ### Adding catalog entities At this point the `catalog-backend` is installed in your backend package, but you will not have any catalog entities loaded. See [Catalog Configuration](https://backstage.io/docs/features/software-catalog/configuration) for how to add locations, or copy the catalog locations from the [create-app template](https://github.com/backstage/backstage/blob/master/packages/create-app/templates/default-app/app-config.yaml.hbs) to get up and running quickly. ## Migrating removed processors `CodeOwnersProcessor` and `AnnotateScmSlugEntityProcessor` are no longer exported by this package. Use the corresponding community modules to retain their behavior: - `CodeOwnersProcessor`: [`@backstage-community/plugin-catalog-backend-module-codeowners`](https://github.com/backstage/community-plugins/tree/main/workspaces/catalog/plugins/catalog-backend-module-codeowners) - `AnnotateScmSlugEntityProcessor`: [`@backstage-community/plugin-catalog-backend-module-annotate-scm-slug`](https://github.com/backstage/community-plugins/tree/main/workspaces/catalog/plugins/catalog-backend-module-annotate-scm-slug) Install the module you need in your backend package and register it with `backend.add(import(''))`. Remove your custom registration of the old processor to avoid registering it twice. If you need to configure a processor explicitly, follow the replacement module's documentation. ## Development This backend plugin can be started in a standalone mode from directly in this package with `yarn start`. However, it will have limited functionality and that process is most convenient when developing the catalog backend plugin itself. To evaluate the catalog and have a greater amount of functionality available, run the entire Backstage example application from the root folder: ```bash # in one terminal window, run this from from the very root of the Backstage project cd packages/backend yarn start ``` This will launch both frontend and backend in the same window, populated with some example entities. ## Links - [catalog](https://github.com/backstage/backstage/tree/master/plugins/catalog) is the frontend interface for this plugin. --- _Source: https://npm.io/package/@backstage/plugin-catalog-backend · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._