feat(core)!: remove legacy cache flag from nx.json (#30787)

docs/generated/devkit/Migration.md

@@ -0,0 +1,22 @@
+# Type alias: Migration
+
+Ƭ **Migration**: (`tree`: [`Tree`](../../devkit/documents/Tree)) => `void` \| `Promise`\<`void`\> \| `string`[] \| `Promise`\<`string`[]\>
+
+Represents a migration that is executed when running `nx migrate`.
+
+Returning a string[] from the migration function will be interpreted as
+a list of next steps to be displayed to the user.
+
+#### Type declaration
+
+▸ (`tree`): `void` \| `Promise`\<`void`\> \| `string`[] \| `Promise`\<`string`[]\>
+
+##### Parameters
+
+| Name   | Type                                  |
+| :----- | :------------------------------------ |
+| `tree` | [`Tree`](../../devkit/documents/Tree) |
+
+##### Returns
+
+`void` \| `Promise`\<`void`\> \| `string`[] \| `Promise`\<`string`[]\>

docs/generated/devkit/NxJsonConfiguration.md

@@ -45,7 +45,6 @@ Nx.json configuration
 - [tui](../../devkit/documents/NxJsonConfiguration#tui): Object
 - [useDaemonProcess](../../devkit/documents/NxJsonConfiguration#usedaemonprocess): boolean
 - [useInferencePlugins](../../devkit/documents/NxJsonConfiguration#useinferenceplugins): boolean
-- [useLegacyCache](../../devkit/documents/NxJsonConfiguration#uselegacycache): boolean
 - [workspaceLayout](../../devkit/documents/NxJsonConfiguration#workspacelayout): Object
 
 ## Properties
@@ -321,14 +320,6 @@ Set this to false to disable adding inference plugins when generating new projec
 
 ---
 
-### useLegacyCache
-
-• `Optional` **useLegacyCache**: `boolean`
-
-Use the legacy file system cache instead of the db cache
-
----
-
 ### workspaceLayout
 
 • `Optional` **workspaceLayout**: `Object`

docs/generated/devkit/README.md

@@ -84,6 +84,7 @@ It only uses language primitives and immutable objects
 - [Hasher](../../devkit/documents/Hasher)
 - [ImplicitDependency](../../devkit/documents/ImplicitDependency)
 - [ImplicitDependencyEntry](../../devkit/documents/ImplicitDependencyEntry)
+- [Migration](../../devkit/documents/Migration)
 - [NxPlugin](../../devkit/documents/NxPlugin)
 - [NxPluginV2](../../devkit/documents/NxPluginV2)
 - [PackageManager](../../devkit/documents/PackageManager)

docs/generated/devkit/Workspace.md

@@ -44,7 +44,6 @@ use ProjectsConfigurations or NxJsonConfiguration
 - [tui](../../devkit/documents/Workspace#tui): Object
 - [useDaemonProcess](../../devkit/documents/Workspace#usedaemonprocess): boolean
 - [useInferencePlugins](../../devkit/documents/Workspace#useinferenceplugins): boolean
-- [useLegacyCache](../../devkit/documents/Workspace#uselegacycache): boolean
 - [version](../../devkit/documents/Workspace#version): number
 - [workspaceLayout](../../devkit/documents/Workspace#workspacelayout): Object
 
@@ -441,18 +440,6 @@ Set this to false to disable adding inference plugins when generating new projec
 
 ---
 
-### useLegacyCache
-
-• `Optional` **useLegacyCache**: `boolean`
-
-Use the legacy file system cache instead of the db cache
-
-#### Inherited from
-
-[NxJsonConfiguration](../../devkit/documents/NxJsonConfiguration).[useLegacyCache](../../devkit/documents/NxJsonConfiguration#uselegacycache)
-
----
-
 ### version
 
 • **version**: `number`

docs/generated/manifests/nx-api.json

@@ -3364,6 +3364,26 @@
       }
     },
     "migrations": {
+      "/nx-api/nx/migrations/remove-legacy-cache": {
+        "description": "Removes the legacy cache configuration from nx.json",
+        "file": "generated/packages/nx/migrations/remove-legacy-cache.json",
+        "hidden": false,
+        "name": "remove-legacy-cache",
+        "version": "21.0.0-beta.8",
+        "originalFilePath": "/packages/nx",
+        "path": "/nx-api/nx/migrations/remove-legacy-cache",
+        "type": "migration"
+      },
+      "/nx-api/nx/migrations/remove-custom-tasks-runner": {
+        "description": "Removes the legacy cache configuration from nx.json",
+        "file": "generated/packages/nx/migrations/remove-custom-tasks-runner.json",
+        "hidden": false,
+        "name": "remove-custom-tasks-runner",
+        "version": "21.0.0-beta.8",
+        "originalFilePath": "/packages/nx",
+        "path": "/nx-api/nx/migrations/remove-custom-tasks-runner",
+        "type": "migration"
+      },
       "/nx-api/nx/migrations/release-version-config-changes": {
         "description": "Updates release version config based on the breaking changes in Nx v21",
         "file": "generated/packages/nx/migrations/release-version-config-changes.json",

docs/generated/packages-metadata.json

@@ -3340,6 +3340,26 @@
       }
     ],
     "migrations": [
+      {
+        "description": "Removes the legacy cache configuration from nx.json",
+        "file": "generated/packages/nx/migrations/remove-legacy-cache.json",
+        "hidden": false,
+        "name": "remove-legacy-cache",
+        "version": "21.0.0-beta.8",
+        "originalFilePath": "/packages/nx",
+        "path": "nx/migrations/remove-legacy-cache",
+        "type": "migration"
+      },
+      {
+        "description": "Removes the legacy cache configuration from nx.json",
+        "file": "generated/packages/nx/migrations/remove-custom-tasks-runner.json",
+        "hidden": false,
+        "name": "remove-custom-tasks-runner",
+        "version": "21.0.0-beta.8",
+        "originalFilePath": "/packages/nx",
+        "path": "nx/migrations/remove-custom-tasks-runner",
+        "type": "migration"
+      },
       {
         "description": "Updates release version config based on the breaking changes in Nx v21",
         "file": "generated/packages/nx/migrations/release-version-config-changes.json",

docs/generated/packages/devkit/documents/nx_devkit.md

@@ -84,6 +84,7 @@ It only uses language primitives and immutable objects
 - [Hasher](../../devkit/documents/Hasher)
 - [ImplicitDependency](../../devkit/documents/ImplicitDependency)
 - [ImplicitDependencyEntry](../../devkit/documents/ImplicitDependencyEntry)
+- [Migration](../../devkit/documents/Migration)
 - [NxPlugin](../../devkit/documents/NxPlugin)
 - [NxPluginV2](../../devkit/documents/NxPluginV2)
 - [PackageManager](../../devkit/documents/PackageManager)

docs/generated/packages/nx/migrations/remove-custom-tasks-runner.json

@@ -0,0 +1,12 @@
+{
+  "name": "remove-custom-tasks-runner",
+  "version": "21.0.0-beta.8",
+  "description": "Removes the legacy cache configuration from nx.json",
+  "implementation": "/packages/nx/src/migrations/update-21-0-0/remove-custom-tasks-runner.ts",
+  "aliases": [],
+  "hidden": false,
+  "path": "/packages/nx",
+  "schema": null,
+  "type": "migration",
+  "examplesFile": "#### Remove Custom Tasks Runners\n\nRemoves `tasksRunnerOptions` entries from `nx.json` that contain custom tasks runners. In Nx 21, custom tasks runners are no longer functional. See /deprecated/custom-tasks-runner for more information.\n\n#### Sample Code Changes\n\nRemoves custom task runner configuration from `nx.json`.\n\n{% tabs %}\n{% tab label=\"Before\" %}\n\n```json {% fileName=\"nx.json\" %}\n{\n  \"targetDefaults\": {},\n  \"tasksRunnerOptions\": {\n    \"default\": {\n      \"runner\": \"custom-task-runner\"\n    }\n  }\n}\n```\n\n{% /tab %}\n{% tab label=\"After\" %}\n\n```json {% fileName=\"nx.json\" %}\n{\n  \"targetDefaults\": {}\n}\n```\n\n{% /tab %}\n{% /tabs %}\n"
+}

docs/generated/packages/nx/migrations/remove-legacy-cache.json

@@ -0,0 +1,12 @@
+{
+  "name": "remove-legacy-cache",
+  "version": "21.0.0-beta.8",
+  "description": "Removes the legacy cache configuration from nx.json",
+  "implementation": "/packages/nx/src/migrations/update-21-0-0/remove-legacy-cache.ts",
+  "aliases": [],
+  "hidden": false,
+  "path": "/packages/nx",
+  "schema": null,
+  "type": "migration",
+  "examplesFile": "#### Use Legacy Cache\n\nRemoves `useLegacyCache` from `nx.json` as it is no longer functional in Nx 21\n\n#### Sample Code Changes\n\n{% tabs %}\n{% tab label=\"Before\" %}\n\n```json {% fileName=\"nx.json\" %}\n{\n  \"targetDefaults\": {},\n  \"useLegacyCache\": true\n}\n```\n\n{% /tab %}\n{% tab label=\"After\" %}\n\n```json {% fileName=\"nx.json\" %}\n{\n  \"targetDefaults\": {}\n}\n```\n\n{% /tab %}\n{% /tabs %}\n"
+}

packages/nx/migrations.json

@@ -33,6 +33,16 @@
       "version": "21.0.0-beta.1",
       "description": "Updates release version config based on the breaking changes in Nx v21",
       "implementation": "./src/migrations/update-21-0-0/release-version-config-changes"
+    },
+    "remove-legacy-cache": {
+      "version": "21.0.0-beta.8",
+      "description": "Removes the legacy cache configuration from nx.json",
+      "implementation": "./src/migrations/update-21-0-0/remove-legacy-cache"
+    },
+    "remove-custom-tasks-runner": {
+      "version": "21.0.0-beta.8",
+      "description": "Removes the legacy cache configuration from nx.json",
+      "implementation": "./src/migrations/update-21-0-0/remove-custom-tasks-runner"
     }
   }
 }

packages/nx/src/command-line/migrate/migrate-ui-api.ts

@@ -135,15 +135,16 @@ export async function runSingleMigration(
     // 2. Bundled into Console, so the version is fixed to what we build Console with.
     const updatedMigrateModule = await import('./migrate.js');
 
-    const fileChanges = await updatedMigrateModule.runNxOrAngularMigration(
+    const { changes: fileChanges } =
-      workspacePath,
+      await updatedMigrateModule.runNxOrAngularMigration(
-      migration,
+        workspacePath,
-      false,
+        migration,
-      configuration.createCommits,
+        false,
-      configuration.commitPrefix || 'chore: [nx migration] ',
+        configuration.createCommits,
-      undefined,
+        configuration.commitPrefix || 'chore: [nx migration] ',
-      true
+        undefined,
-    );
+        true
+      );
 
     const gitRefAfter = execSync('git rev-parse HEAD', {
       cwd: workspacePath,

packages/nx/src/command-line/migrate/migrate.ts

@@ -1474,11 +1474,11 @@ export async function executeMigrations(
     logger.info(`- ${m.package}: ${m.name} (${m.description})`)
   );
   logger.info(`---------------------------------------------------------\n`);
-
+  const allNextSteps: string[] = [];
   for (const m of sortedMigrations) {
     logger.info(`Running migration ${m.package}: ${m.name}`);
     try {
-      const changes = await runNxOrAngularMigration(
+      const { changes, nextSteps } = await runNxOrAngularMigration(
         root,
         m,
         isVerbose,
@@ -1486,6 +1486,7 @@ export async function executeMigrations(
         commitPrefix,
         () => changedDepInstaller.installDepsIfChanged()
       );
+      allNextSteps.push(...nextSteps);
       if (changes.length === 0) {
         migrationsWithNoChanges.push(m);
       }
@@ -1502,7 +1503,7 @@ export async function executeMigrations(
     changedDepInstaller.installDepsIfChanged();
   }
 
-  return migrationsWithNoChanges;
+  return { migrationsWithNoChanges, nextSteps: allNextSteps };
 }
 
 class ChangedDepInstaller {
@@ -1533,7 +1534,7 @@ export async function runNxOrAngularMigration(
   commitPrefix: string,
   installDepsIfChanged?: () => void,
   handleInstallDeps = false
-): Promise<FileChange[]> {
+): Promise<{ changes: FileChange[]; nextSteps: string[] }> {
   if (!installDepsIfChanged) {
     const changedDepInstaller = new ChangedDepInstaller(root);
     installDepsIfChanged = () => changedDepInstaller.installDepsIfChanged();
@@ -1543,19 +1544,20 @@ export async function runNxOrAngularMigration(
     root
   );
   let changes: FileChange[] = [];
+  let nextSteps: string[] = [];
   if (!isAngularMigration(collection, migration.name)) {
-    changes = await runNxMigration(
+    ({ nextSteps, changes } = await runNxMigration(
       root,
       collectionPath,
       collection,
       migration.name
-    );
+    ));
 
     logger.info(`Ran ${migration.name} from ${migration.package}`);
     logger.info(`  ${migration.description}\n`);
     if (changes.length < 1) {
       logger.info(`No changes were made\n`);
-      return [];
+      return { changes, nextSteps };
     }
 
     logger.info('Changes:');
@@ -1576,7 +1578,7 @@ export async function runNxOrAngularMigration(
     logger.info(`  ${migration.description}\n`);
     if (!madeChanges) {
       logger.info(`No changes were made\n`);
-      return [];
+      return { changes, nextSteps };
     }
 
     logger.info('Changes:');
@@ -1608,7 +1610,7 @@ export async function runNxOrAngularMigration(
     installDepsIfChanged();
   }
 
-  return changes;
+  return { changes, nextSteps };
 }
 
 async function runMigrations(
@@ -1662,7 +1664,7 @@ async function runMigrations(
     version: string;
   }[] = readJsonFile(join(root, opts.runMigrations)).migrations;
 
-  const migrationsWithNoChanges = await executeMigrations(
+  const { migrationsWithNoChanges, nextSteps } = await executeMigrations(
     root,
     migrations,
     isVerbose,
@@ -1679,6 +1681,12 @@ async function runMigrations(
       title: `No changes were made from running '${opts.runMigrations}'. This workspace is up to date!`,
     });
   }
+  if (nextSteps.length > 0) {
+    output.log({
+      title: `Some migrations have additional information, see below.`,
+      bodyLines: nextSteps.map((line) => `- ${line}`),
+    });
+  }
 }
 
 function getStringifiedPackageJsonDeps(root: string): string {
@@ -1712,11 +1720,18 @@ async function runNxMigration(
     process.env.NX_VERBOSE_LOGGING === 'true',
     `migration ${collection.name}:${name}`
   );
-  await fn(host, {});
+  let nextSteps = await fn(host, {});
+  // This accounts for migrations that mistakenly return a generator callback
+  // from a migration. We've never executed these, so its not a breaking change that
+  // we don't call them now... but currently shipping a migration with one wouldn't break
+  // the migrate flow, so we are being cautious.
+  if (!isStringArray(nextSteps)) {
+    nextSteps = [];
+  }
   host.lock();
   const changes = host.listChanges();
   flushChanges(root, changes);
-  return changes;
+  return { changes, nextSteps };
 }
 
 export async function migrate(
@@ -1905,3 +1920,10 @@ const getNgCompatLayer = (() => {
     return _ngCliAdapter;
   };
 })();
+
+function isStringArray(value: unknown): value is string[] {
+  if (!Array.isArray(value)) {
+    return false;
+  }
+  return value.every((v) => typeof v === 'string');
+}

packages/nx/src/command-line/repair/repair.ts

@@ -25,7 +25,7 @@ export async function repair(
     );
 
     const migrations = [...nxMigrations, ...extraMigrations];
-    const migrationsThatMadeNoChanges = await executeMigrations(
+    const { migrationsWithNoChanges, nextSteps } = await executeMigrations(
       process.cwd(),
       migrations,
       args.verbose,
@@ -33,7 +33,7 @@ export async function repair(
       ''
     );
 
-    if (migrationsThatMadeNoChanges.length < migrations.length) {
+    if (migrationsWithNoChanges.length < migrations.length) {
       output.success({
         title: `Successfully repaired your configuration. This workspace is up to date!`,
       });
@@ -42,5 +42,11 @@ export async function repair(
         title: `No changes were necessary. This workspace is up to date!`,
       });
     }
+    if (nextSteps.length) {
+      output.log({
+        title: 'Some repairs have additional information, see below.',
+        bodyLines: nextSteps.map((line) => `  - ${line}`),
+      });
+    }
   });
 }

packages/nx/src/command-line/report/report.ts

@@ -303,7 +303,7 @@ export async function getReportData(): Promise<ReportData> {
     }
   }
 
-  let cache = dbCacheEnabled(nxJson)
+  let cache = dbCacheEnabled()
     ? {
         max:
           nxJson.maxCacheSize !== undefined

packages/nx/src/config/misc-interfaces.ts

@@ -7,7 +7,8 @@ import {
 } from './workspace-json-project-json';
 
 import type { NxJsonConfiguration } from './nx-json';
-import { Schema } from '../utils/params';
+import type { Schema } from '../utils/params';
+import type { Tree } from '../generators/tree';
 /**
  * A callback function that is executed after changes are made to the file system
  */
@@ -66,6 +67,16 @@ export type PackageJsonUpdates = {
   };
 };
 
+/**
+ * Represents a migration that is executed when running `nx migrate`.
+ *
+ * Returning a string[] from the migration function will be interpreted as
+ * a list of next steps to be displayed to the user.
+ */
+export type Migration = (
+  tree: Tree
+) => void | Promise<void> | string[] | Promise<string[]>;
+
 export interface MigrationsJsonEntry {
   version: string;
   description?: string;

packages/nx/src/config/nx-json.ts

@@ -651,11 +651,6 @@ export interface NxJsonConfiguration<T = '*' | string[]> {
    */
   sync?: NxSyncConfiguration;
 
-  /**
-   * Use the legacy file system cache instead of the db cache
-   */
-  useLegacyCache?: boolean;
-
   /**
    * Sets the maximum size of the local cache. Accepts a number followed by a unit (e.g. 100MB). Accepted units are B, KB, MB, and GB.
    */

packages/nx/src/devkit-exports.ts

@@ -26,6 +26,7 @@ export type {
  */
 export type {
   Generator,
+  Migration,
   GeneratorCallback,
   PromiseExecutor,
   AsyncIteratorExecutor,

packages/nx/src/migrations/update-20-0-1/use-legacy-cache.ts

@@ -14,7 +14,9 @@ export default async function update(tree: Tree) {
   if ((nxJson as any).enableDbCache) {
     delete (nxJson as any).enableDbCache;
   } else {
-    nxJson.useLegacyCache = true;
+    (
+      nxJson as NxJsonConfiguration & { useLegacyCache: boolean }
+    ).useLegacyCache = true;
   }
 
   updateNxJson(tree, nxJson);

packages/nx/src/migrations/update-21-0-0/remove-custom-tasks-runner.md

@@ -0,0 +1,33 @@
+#### Remove Custom Tasks Runners
+
+Removes `tasksRunnerOptions` entries from `nx.json` that contain custom tasks runners. In Nx 21, custom tasks runners are no longer functional. See /deprecated/custom-tasks-runner for more information.
+
+#### Sample Code Changes
+
+Removes custom task runner configuration from `nx.json`.
+
+{% tabs %}
+{% tab label="Before" %}
+
+```json {% fileName="nx.json" %}
+{
+  "targetDefaults": {},
+  "tasksRunnerOptions": {
+    "default": {
+      "runner": "custom-task-runner"
+    }
+  }
+}
+```
+
+{% /tab %}
+{% tab label="After" %}
+
+```json {% fileName="nx.json" %}
+{
+  "targetDefaults": {}
+}
+```
+
+{% /tab %}
+{% /tabs %}

packages/nx/src/migrations/update-21-0-0/remove-custom-tasks-runner.spec.ts

@@ -0,0 +1,140 @@
+import { createTreeWithEmptyWorkspace } from '../../generators/testing-utils/create-tree-with-empty-workspace';
+import { Tree } from '../../generators/tree';
+
+import update from './remove-custom-tasks-runner';
+import { readNxJson, updateNxJson } from '../../generators/utils/nx-json';
+
+describe('remove custom tasks runners', () => {
+  let tree: Tree;
+
+  beforeEach(() => {
+    tree = createTreeWithEmptyWorkspace();
+  });
+
+  it('should remove all tasks runners that contain a custom runner', async () => {
+    updateNxJson(tree, {
+      tasksRunnerOptions: {
+        default: {
+          runner: 'nx-cloud',
+          options: {
+            cacheableOperations: ['build', 'lint'],
+          },
+        },
+        other: {
+          runner: 'some-other-runner',
+          options: {
+            cacheableOperations: ['test'],
+          },
+        },
+        custom: {
+          runner: 'custom-runner',
+          options: {
+            cacheableOperations: ['build', 'lint'],
+          },
+        },
+      },
+    });
+    await update(tree);
+
+    expect(readNxJson(tree)).toMatchInlineSnapshot(`
+      {
+        "tasksRunnerOptions": {
+          "default": {
+            "options": {
+              "cacheableOperations": [
+                "build",
+                "lint",
+              ],
+            },
+            "runner": "nx-cloud",
+          },
+        },
+      }
+    `);
+  });
+
+  it('should remove whole tasksRunnerOptions if all runners are removed', async () => {
+    updateNxJson(tree, {
+      tasksRunnerOptions: {
+        default: {
+          runner: 'custom-runner',
+          options: {
+            cacheableOperations: ['build', 'lint'],
+          },
+        },
+      },
+    });
+    await update(tree);
+    expect(readNxJson(tree)).toMatchInlineSnapshot(`{}`);
+  });
+
+  it('should provide a link to the migration guide for nx-aws-cache', async () => {
+    updateNxJson(tree, {
+      tasksRunnerOptions: {
+        default: {
+          runner: '@nx-aws-cache/nx-aws-cache',
+          options: {
+            cacheableOperations: ['build', 'lint'],
+          },
+        },
+      },
+    });
+    const nextSteps = await update(tree);
+    expect(nextSteps).toMatchInlineSnapshot(`
+      [
+        "Nx 21 removed support for custom task runners. For more information, please check: https://nx.dev/deprecated/custom-tasks-runner#migrating-from-nxawsplugin",
+      ]
+    `);
+  });
+
+  it('should not remove tasks runner if it is not custom', async () => {
+    updateNxJson(tree, {
+      tasksRunnerOptions: {
+        default: {
+          runner: 'nx-cloud',
+          options: {
+            cacheableOperations: ['build', 'lint'],
+          },
+        },
+      },
+    });
+    const nextSteps = await update(tree);
+
+    expect(readNxJson(tree)).toMatchInlineSnapshot(`
+      {
+        "tasksRunnerOptions": {
+          "default": {
+            "options": {
+              "cacheableOperations": [
+                "build",
+                "lint",
+              ],
+            },
+            "runner": "nx-cloud",
+          },
+        },
+      }
+    `);
+    expect(nextSteps).toHaveLength(0);
+  });
+
+  it('should provide a link to the migration guide for other custom runners', async () => {
+    updateNxJson(tree, {
+      tasksRunnerOptions: {
+        default: {
+          runner: 'custom-runner',
+          options: {
+            cacheableOperations: ['build', 'lint'],
+          },
+        },
+      },
+    });
+    const nextSteps = await update(tree);
+    expect(nextSteps).toMatchInlineSnapshot(`
+      [
+        "Nx 21 removed support for custom task runners. For more information, please check: https://nx.dev/deprecated/custom-tasks-runner",
+      ]
+    `);
+    expect(readNxJson(tree)).toMatchInlineSnapshot(`{}`);
+  });
+});

packages/nx/src/migrations/update-21-0-0/remove-custom-tasks-runner.ts

@@ -0,0 +1,47 @@
+import { Tree } from '../../generators/tree';
+import { formatChangedFilesWithPrettierIfAvailable } from '../../generators/internal-utils/format-changed-files-with-prettier-if-available';
+import { readNxJson, updateNxJson } from '../../generators/utils/nx-json';
+import { NxJsonConfiguration } from '../../config/nx-json';
+
+function isCustomRunnerPath(modulePath: string) {
+  return !['nx-cloud', '@nrwl/nx-cloud', 'nx/tasks-runners/default'].includes(
+    modulePath
+  );
+}
+
+export default async function update(tree: Tree) {
+  const nxJson = readNxJson(tree) as NxJsonConfiguration;
+
+  if (!nxJson?.tasksRunnerOptions) {
+    return;
+  }
+
+  const nextSteps: string[] = [];
+
+  for (const key in nxJson.tasksRunnerOptions) {
+    const runner = nxJson.tasksRunnerOptions[key].runner;
+
+    if (runner && isCustomRunnerPath(runner)) {
+      let nextStepText =
+        'Nx 21 removed support for custom task runners. For more information, please check: ';
+      if (runner === '@nx-aws-cache/nx-aws-cache') {
+        nextStepText +=
+          'https://nx.dev/deprecated/custom-tasks-runner#migrating-from-nxawsplugin';
+      } else {
+        nextStepText += 'https://nx.dev/deprecated/custom-tasks-runner';
+      }
+      if (nextSteps.length === 0) {
+        nextSteps.push(nextStepText);
+      }
+      delete nxJson.tasksRunnerOptions[key];
+    }
+  }
+  if (Object.keys(nxJson.tasksRunnerOptions).length === 0) {
+    delete nxJson.tasksRunnerOptions;
+  }
+
+  updateNxJson(tree, nxJson);
+
+  await formatChangedFilesWithPrettierIfAvailable(tree);
+  return nextSteps;
+}

packages/nx/src/migrations/update-21-0-0/remove-legacy-cache.md

@@ -0,0 +1,27 @@
+#### Use Legacy Cache
+
+Removes `useLegacyCache` from `nx.json` as it is no longer functional in Nx 21
+
+#### Sample Code Changes
+
+{% tabs %}
+{% tab label="Before" %}
+
+```json {% fileName="nx.json" %}
+{
+  "targetDefaults": {},
+  "useLegacyCache": true
+}
+```
+
+{% /tab %}
+{% tab label="After" %}
+
+```json {% fileName="nx.json" %}
+{
+  "targetDefaults": {}
+}
+```
+
+{% /tab %}
+{% /tabs %}

packages/nx/src/migrations/update-21-0-0/remove-legacy-cache.ts

@@ -0,0 +1,21 @@
+import { Tree } from '../../generators/tree';
+import { formatChangedFilesWithPrettierIfAvailable } from '../../generators/internal-utils/format-changed-files-with-prettier-if-available';
+import { readNxJson, updateNxJson } from '../../generators/utils/nx-json';
+import { NxJsonConfiguration } from '../../config/nx-json';
+
+export default async function update(tree: Tree) {
+  const nxJson = readNxJson(tree) as NxJsonConfiguration;
+
+  if (!nxJson) {
+    return;
+  }
+
+  // If workspaces  had `useLegacyCache` we can just delete the property as the property is not functional in nx v21
+  if ((nxJson as any).useLegacyCache) {
+    delete (nxJson as any).useLegacyCache;
+  }
+
+  updateNxJson(tree, nxJson);
+
+  await formatChangedFilesWithPrettierIfAvailable(tree);
+}

packages/nx/src/tasks-runner/cache.ts

@@ -37,32 +37,7 @@ export type CachedResult = {
 export type TaskWithCachedResult = { task: Task; cachedResult: CachedResult };
 
 // This function is called once during tasks runner initialization. It checks if the db cache is enabled and logs a warning if it is not.
-export function dbCacheEnabled(nxJson: NxJsonConfiguration = readNxJson()) {
+export function dbCacheEnabled() {
-  // If the user has explicitly disabled the db cache, we can warn...
-  if (
-    nxJson.useLegacyCache ||
-    process.env.NX_DISABLE_DB === 'true' ||
-    process.env.NX_DB_CACHE === 'false'
-  ) {
-    let readMoreLink = 'https://nx.dev/deprecated/legacy-cache';
-    if (
-      nxJson.tasksRunnerOptions?.default?.runner &&
-      !['nx-cloud', 'nx/tasks-runners/default', '@nrwl/nx-cloud'].includes(
-        nxJson.tasksRunnerOptions.default.runner
-      )
-    ) {
-      readMoreLink += '#tasksrunneroptions';
-    } else if (
-      process.env.NX_REJECT_UNKNOWN_LOCAL_CACHE === '0' ||
-      process.env.NX_REJECT_UNKNOWN_LOCAL_CACHE === 'false'
-    ) {
-      readMoreLink += '#nxrejectunknownlocalcache';
-    }
-    logger.warn(
-      `Nx is configured to use the legacy cache. This cache will be removed in Nx 21. Read more at ${readMoreLink}.`
-    );
-    return false;
-  }
   // ...but if on wasm and the the db cache isnt supported we shouldn't warn
   if (IS_WASM) {
     return false;
@@ -85,7 +60,7 @@ export function dbCacheEnabled(nxJson: NxJsonConfiguration = readNxJson()) {
 // Do not change the order of these arguments as this function is used by nx cloud
 export function getCache(options: DefaultTasksRunnerOptions): DbCache | Cache {
   const nxJson = readNxJson();
-  return dbCacheEnabled(nxJson)
+  return dbCacheEnabled()
     ? new DbCache({
         // Remove this in Nx 21
         nxCloudRemoteCache: isNxCloudUsed(nxJson) ? options.remoteCache : null,

packages/nx/src/tasks-runner/run-command.spec.ts

@@ -15,66 +15,6 @@ describe('getRunner', () => {
     mockRunner = jest.fn();
   });
 
-  it('gets a custom task runner', () => {
-    jest.mock('custom-runner', () => mockRunner, {
-      virtual: true,
-    });
-
-    nxJson.tasksRunnerOptions = {
-      custom: {
-        runner: 'custom-runner',
-      },
-    };
-
-    const { tasksRunner, runnerOptions } = getRunner(
-      { runner: 'custom' },
-      nxJson
-    );
-
-    expect(tasksRunner).toEqual(mockRunner);
-  });
-
-  it('gets a custom task runner with options', () => {
-    jest.mock('custom-runner2', () => mockRunner, {
-      virtual: true,
-    });
-
-    nxJson.tasksRunnerOptions = {
-      custom: {
-        runner: 'custom-runner2',
-        options: {
-          runnerOption: 'runner-option',
-        },
-      },
-    };
-
-    const { tasksRunner, runnerOptions } = getRunner(
-      { runner: 'custom' },
-      nxJson
-    );
-    expect(tasksRunner).toBe(mockRunner);
-    expect(runnerOptions).toEqual({
-      runner: 'custom',
-      runnerOption: 'runner-option',
-    });
-  });
-
-  it('gets a custom defined default task runner', () => {
-    jest.mock('custom-default-runner', () => mockRunner, {
-      virtual: true,
-    });
-
-    nxJson.tasksRunnerOptions = {
-      default: {
-        runner: 'custom-default-runner',
-      },
-    };
-
-    const { tasksRunner } = getRunner({}, nxJson);
-
-    expect(tasksRunner).toEqual(mockRunner);
-  });
-
   it('uses default runner when no tasksRunnerOptions are present', () => {
     jest.mock(join(__dirname, './default-tasks-runner.ts'), () => mockRunner);
 

packages/nx/src/tasks-runner/run-command.ts

@@ -1064,15 +1064,6 @@ export function getRunner(
   const modulePath: string = getTasksRunnerPath(runner, nxJson);
 
   try {
-    if (isCustomRunnerPath(modulePath)) {
-      output.warn({
-        title: `Custom task runners will be replaced by a new API starting with Nx 21.`,
-        bodyLines: [
-          `For more information, see https://nx.dev/deprecated/custom-tasks-runner`,
-        ],
-      });
-    }
-
     const tasksRunner = loadTasksRunner(modulePath);
 
     return {
@@ -1095,20 +1086,14 @@ function getTasksRunnerPath(
   runner: string,
   nxJson: NxJsonConfiguration<string[] | '*'>
 ) {
-  let modulePath: string = nxJson.tasksRunnerOptions?.[runner]?.runner;
-
-  if (modulePath) {
-    if (isRelativePath(modulePath)) {
-      return join(workspaceRoot, modulePath);
-    }
-    return modulePath;
-  }
-
   const isCloudRunner =
     // No tasksRunnerOptions for given --runner
     nxJson.nxCloudAccessToken ||
     // No runner prop in tasks runner options, check if access token is set.
     nxJson.tasksRunnerOptions?.[runner]?.options?.accessToken ||
+    ['nx-cloud', '@nrwl/nx-cloud'].includes(
+      nxJson.tasksRunnerOptions?.[runner]?.runner
+    ) ||
     // Cloud access token specified in env var.
     process.env.NX_CLOUD_ACCESS_TOKEN ||
     // Nx Cloud ID specified in nxJson
@@ -1177,12 +1162,3 @@ export function getRunnerOptions(
 
   return result;
 }
-
-function isCustomRunnerPath(modulePath: string) {
-  return ![
-    'nx-cloud',
-    '@nrwl/nx-cloud',
-    'nx/tasks-runners/default',
-    defaultTasksRunnerPath,
-  ].includes(modulePath);
-}

packages/nx/src/tasks-runner/task-orchestrator.ts

@@ -290,7 +290,7 @@ export class TaskOrchestrator {
       // No output files to restore
       !!outputs.length &&
       // Remote caches are restored to output dirs when applied and using db cache
-      (!cachedResult.remote || !dbCacheEnabled(this.nxJson)) &&
+      (!cachedResult.remote || !dbCacheEnabled()) &&
       // Output files have not been touched since last run
       (await this.shouldCopyOutputsFromCache(outputs, task.hash));
     if (shouldCopyOutputsFromCache) {