Migration and Deprecation Checklist:

• Remove `src/run.ts` and associated files
• Update `dev/index.ts` to use the new backend system
• Delete the `src/dynamic` directory
• Delete the `src/alpha.ts` file
• If applicable, update `src/index.ts` to export the plugin/module as `default`
  • If there are multiple modules/plugins in a package, reference the `ocm-backend` PR. Please notify pschultz@redhat.com as well.
• Remove all references to `alpha` in `package.json`
• If applicable, remove the `@backstage/backend-dynamic-feature-service` dependency
• Remove all references to `backstage/backend-common` and remove the dependency
• Update tests to use `startTestBackend` (if applicable)
  • Update module/plugin-specific tests to use `startTestBackend`
  • Do not migrate provider-specific tests to `startTestBackend`
  • Examples provided in referenced PRs
• Update providers (if applicable) to use `deps` for required services and `options` for optional args
• Use `backstage/errors` when applicable
• Update `config.d.ts`
• Review the dependencies to determine if any can be moved to devDependencies by using the type modifier in the import statement. For example, change import { LoggerService } from '@backstage/backend-plugin-api'; to import type { LoggerService } from '@backstage/backend-plugin-api';. If the dependency is only used for type imports, it can be safely moved to a devDependency.
• Clean up unused dependencies in `package.json`
• Remove `express-service-static-core` and `express-promise-router`
  • Replace `import { Request } from 'express-serve-static-core';` with `import { Request } from 'express';`
  • Replace `import Router from "express-promise-router";` with `import { Router } from 'express';` and change the types to `Promise<Router>`
• Run `yarn export-dynamic --clean` if applicable
• Remove legacy backend references in `README.md`
• Going forward, we should avoid manually mocking any services.  Refer to the OCM router tests here.

Example PRs:

• https://github.com/janus-idp/backstage-plugins/pull/2189
• https://github.com/janus-idp/backstage-plugins/pull/2104