diff --git a/packages/schematics/angular/application/index.ts b/packages/schematics/angular/application/index.ts
index 295c65ba93ca..95c8380b0817 100644
--- a/packages/schematics/angular/application/index.ts
+++ b/packages/schematics/angular/application/index.ts
@@ -396,13 +396,9 @@ function addAppToWorkspaceFile(options: ApplicationOptions, appDir: string): Rul
                 options: {},
               }
             : {
-                builder: Builders.BuildKarma,
+                builder: Builders.BuildUnitTest,
                 options: {
-                  polyfills: options.zoneless ? undefined : ['zone.js', 'zone.js/testing'],
-                  tsConfig: `${projectRoot}tsconfig.spec.json`,
-                  inlineStyleLanguage,
-                  assets: [{ 'glob': '**/*', 'input': `${projectRoot}public` }],
-                  styles: [`${sourceRoot}/styles.${options.style}`],
+                  runner: 'karma',
                 },
               },
     },
diff --git a/packages/schematics/angular/application/index_spec.ts b/packages/schematics/angular/application/index_spec.ts
index e1867b24cf41..5c56e2ca7a4d 100644
--- a/packages/schematics/angular/application/index_spec.ts
+++ b/packages/schematics/angular/application/index_spec.ts
@@ -448,10 +448,11 @@ describe('Application Schematic', () => {
       const config = JSON.parse(tree.readContent('/angular.json'));
       const prj = config.projects.foo;
       const testOpt = prj.architect.test;
-      expect(testOpt.builder).toEqual('@angular/build:karma');
-      expect(testOpt.options.tsConfig).toEqual('tsconfig.spec.json');
-      expect(testOpt.options.assets).toEqual([{ glob: '**/*', input: 'public' }]);
-      expect(testOpt.options.styles).toEqual(['src/styles.css']);
+      expect(testOpt.builder).toEqual('@angular/build:unit-test');
+      expect(testOpt.options.runner).toEqual('karma');
+      expect(testOpt.options.tsConfig).toBeUndefined();
+      expect(testOpt.options.assets).toBeUndefined();
+      expect(testOpt.options.styles).toBeUndefined();
     });
 
     it('should set the relative tsconfig paths', async () => {
diff --git a/packages/schematics/angular/config/index.ts b/packages/schematics/angular/config/index.ts
index 209ac0de91f9..6bfd36f41b84 100644
--- a/packages/schematics/angular/config/index.ts
+++ b/packages/schematics/angular/config/index.ts
@@ -47,49 +47,88 @@ async function addBrowserslistConfig(projectRoot: string): Promise<Rule> {
 }
 
 function addKarmaConfig(options: ConfigOptions): Rule {
-  return updateWorkspace((workspace) => {
-    const project = workspace.projects.get(options.project);
-    if (!project) {
-      throw new SchematicsException(`Project name "${options.project}" doesn't not exist.`);
-    }
+  return (_, context) =>
+    updateWorkspace((workspace) => {
+      const project = workspace.projects.get(options.project);
+      if (!project) {
+        throw new SchematicsException(`Project name "${options.project}" doesn't not exist.`);
+      }
 
-    const testTarget = project.targets.get('test');
-    if (!testTarget) {
-      throw new SchematicsException(
-        `No "test" target found for project "${options.project}".` +
-          ' A "test" target is required to generate a karma configuration.',
-      );
-    }
+      const testTarget = project.targets.get('test');
+      if (!testTarget) {
+        throw new SchematicsException(
+          `No "test" target found for project "${options.project}".` +
+            ' A "test" target is required to generate a karma configuration.',
+        );
+      }
 
-    if (
-      testTarget.builder !== AngularBuilder.Karma &&
-      testTarget.builder !== AngularBuilder.BuildKarma
-    ) {
-      throw new SchematicsException(
-        `Cannot add a karma configuration as builder for "test" target in project does not` +
-          ` use "${AngularBuilder.Karma}" or "${AngularBuilder.BuildKarma}".`,
-      );
-    }
+      if (
+        testTarget.builder !== AngularBuilder.Karma &&
+        testTarget.builder !== AngularBuilder.BuildKarma &&
+        testTarget.builder !== AngularBuilder.BuildUnitTest
+      ) {
+        throw new SchematicsException(
+          `Cannot add a karma configuration as builder for "test" target in project does not` +
+            ` use "${AngularBuilder.Karma}", "${AngularBuilder.BuildKarma}", or ${AngularBuilder.BuildUnitTest}.`,
+        );
+      }
+
+      testTarget.options ??= {};
+      if (testTarget.builder !== AngularBuilder.BuildUnitTest) {
+        testTarget.options.karmaConfig = path.join(project.root, 'karma.conf.js');
+      } else {
+        // `unit-test` uses the `runnerConfig` option which has configuration discovery if enabled
+        testTarget.options.runnerConfig = true;
 
-    testTarget.options ??= {};
-    testTarget.options.karmaConfig = path.join(project.root, 'karma.conf.js');
+        let isKarmaRunnerConfigured = false;
+        // Check runner option
+        if (testTarget.options.runner) {
+          if (testTarget.options.runner === 'karma') {
+            isKarmaRunnerConfigured = true;
+          } else {
+            context.logger.warn(
+              `The "test" target is configured to use a runner other than "karma" in the main options.` +
+                ' The generated "karma.conf.js" file may not be used.',
+            );
+          }
+        }
 
-    // If scoped project (i.e. "@foo/bar"), convert dir to "foo/bar".
-    let folderName = options.project.startsWith('@') ? options.project.slice(1) : options.project;
-    if (/[A-Z]/.test(folderName)) {
-      folderName = strings.dasherize(folderName);
-    }
+        for (const [name, config] of Object.entries(testTarget.configurations ?? {})) {
+          if (config && typeof config === 'object' && 'runner' in config) {
+            if (config.runner !== 'karma') {
+              context.logger.warn(
+                `The "test" target's "${name}" configuration is configured to use a runner other than "karma".` +
+                  ' The generated "karma.conf.js" file may not be used for that configuration.',
+              );
+            } else {
+              isKarmaRunnerConfigured = true;
+            }
+          }
+        }
 
-    return mergeWith(
-      apply(url('https://github.com/files'), [
-        filter((p) => p.endsWith('karma.conf.js.template')),
-        applyTemplates({
-          relativePathToWorkspaceRoot: relativePathToWorkspaceRoot(project.root),
-          folderName,
-          needDevkitPlugin: testTarget.builder === AngularBuilder.Karma,
-        }),
-        move(project.root),
-      ]),
-    );
-  });
+        if (!isKarmaRunnerConfigured) {
+          context.logger.warn(
+            `The "test" target is not explicitly configured to use the "karma" runner.` +
+              ' The generated "karma.conf.js" file may not be used as the default runner is "vitest".',
+          );
+        }
+      }
+      // If scoped project (i.e. "@foo/bar"), convert dir to "foo/bar".
+      let folderName = options.project.startsWith('@') ? options.project.slice(1) : options.project;
+      if (/[A-Z]/.test(folderName)) {
+        folderName = strings.dasherize(folderName);
+      }
+
+      return mergeWith(
+        apply(url('https://github.com/files'), [
+          filter((p) => p.endsWith('karma.conf.js.template')),
+          applyTemplates({
+            relativePathToWorkspaceRoot: relativePathToWorkspaceRoot(project.root),
+            folderName,
+            needDevkitPlugin: testTarget.builder === AngularBuilder.Karma,
+          }),
+          move(project.root),
+        ]),
+      );
+    });
 }
diff --git a/packages/schematics/angular/config/index_spec.ts b/packages/schematics/angular/config/index_spec.ts
index 1bbc08d9e85b..a63a58ab6887 100644
--- a/packages/schematics/angular/config/index_spec.ts
+++ b/packages/schematics/angular/config/index_spec.ts
@@ -95,6 +95,88 @@ describe('Config Schematic', () => {
       const { karmaConfig } = prj.architect.test.options;
       expect(karmaConfig).toBe('projects/foo/karma.conf.js');
     });
+
+    describe('with "unit-test" builder', () => {
+      beforeEach(() => {
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        const angularJson = applicationTree.readJson('angular.json') as any;
+        angularJson.projects.foo.architect.test.builder = '@angular/build:unit-test';
+        applicationTree.overwrite('angular.json', JSON.stringify(angularJson));
+      });
+
+      it(`should not set 'karmaConfig' in test builder`, async () => {
+        const tree = await runConfigSchematic(ConfigType.Karma);
+        const config = JSON.parse(tree.readContent('/angular.json'));
+        const prj = config.projects.foo;
+        const { karmaConfig } = prj.architect.test.options;
+        expect(karmaConfig).toBeUndefined();
+      });
+
+      it(`should warn when 'runner' is not specified`, async () => {
+        const logs: string[] = [];
+        schematicRunner.logger.subscribe(({ message }) => logs.push(message));
+        await runConfigSchematic(ConfigType.Karma);
+        expect(
+          logs.some((v) => v.includes('may not be used as the default runner is "vitest"')),
+        ).toBeTrue();
+      });
+
+      it(`should warn when 'runner' is 'vitest' in options`, async () => {
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        const angularJson = applicationTree.readJson('angular.json') as any;
+        angularJson.projects.foo.architect.test.options ??= {};
+        angularJson.projects.foo.architect.test.options.runner = 'vitest';
+        applicationTree.overwrite('angular.json', JSON.stringify(angularJson));
+
+        const logs: string[] = [];
+        schematicRunner.logger.subscribe(({ message }) => logs.push(message));
+        await runConfigSchematic(ConfigType.Karma);
+        expect(
+          logs.some((v) => v.includes('runner other than "karma" in the main options')),
+        ).toBeTrue();
+      });
+
+      it(`should warn when 'runner' is 'vitest' in a configuration`, async () => {
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        const angularJson = applicationTree.readJson('angular.json') as any;
+        angularJson.projects.foo.architect.test.configurations ??= {};
+        angularJson.projects.foo.architect.test.configurations.ci = { runner: 'vitest' };
+        applicationTree.overwrite('angular.json', JSON.stringify(angularJson));
+
+        const logs: string[] = [];
+        schematicRunner.logger.subscribe(({ message }) => logs.push(message));
+        await runConfigSchematic(ConfigType.Karma);
+        expect(
+          logs.some((v) => v.includes(`"ci" configuration is configured to use a runner`)),
+        ).toBeTrue();
+      });
+
+      it(`should not warn when 'runner' is 'karma' in options`, async () => {
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        const angularJson = applicationTree.readJson('angular.json') as any;
+        angularJson.projects.foo.architect.test.options ??= {};
+        angularJson.projects.foo.architect.test.options.runner = 'karma';
+        applicationTree.overwrite('angular.json', JSON.stringify(angularJson));
+
+        const logs: string[] = [];
+        schematicRunner.logger.subscribe(({ message }) => logs.push(message));
+        await runConfigSchematic(ConfigType.Karma);
+        expect(logs.length).toBe(0);
+      });
+
+      it(`should not warn when 'runner' is 'karma' in a configuration`, async () => {
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        const angularJson = applicationTree.readJson('angular.json') as any;
+        angularJson.projects.foo.architect.test.configurations ??= {};
+        angularJson.projects.foo.architect.test.configurations.ci = { runner: 'karma' };
+        applicationTree.overwrite('angular.json', JSON.stringify(angularJson));
+
+        const logs: string[] = [];
+        schematicRunner.logger.subscribe(({ message }) => logs.push(message));
+        await runConfigSchematic(ConfigType.Karma);
+        expect(logs.length).toBe(0);
+      });
+    });
   });
 
   describe(`when 'type' is 'browserslist'`, () => {
diff --git a/packages/schematics/angular/ng-new/index_spec.ts b/packages/schematics/angular/ng-new/index_spec.ts
index 20306b875a9a..7f136908c747 100644
--- a/packages/schematics/angular/ng-new/index_spec.ts
+++ b/packages/schematics/angular/ng-new/index_spec.ts
@@ -169,7 +169,8 @@ describe('Ng New Schematic', () => {
         },
       },
     } = JSON.parse(tree.readContent('/bar/angular.json'));
-    expect(test.builder).toBe('@angular/build:karma');
+    expect(test.builder).toBe('@angular/build:unit-test');
+    expect(test.options).toEqual({ runner: 'karma' });
 
     const { devDependencies } = JSON.parse(tree.readContent('/bar/package.json'));
     expect(devDependencies['karma']).toBeDefined();
diff --git a/tests/legacy-cli/e2e/initialize/500-create-project.ts b/tests/legacy-cli/e2e/initialize/500-create-project.ts
index c6c0f8ef243d..b48c8733a9a5 100644
--- a/tests/legacy-cli/e2e/initialize/500-create-project.ts
+++ b/tests/legacy-cli/e2e/initialize/500-create-project.ts
@@ -64,6 +64,9 @@ export default async function () {
 
         const test = json['projects']['test-project']['architect']['test'];
         test.builder = '@angular-devkit/build-angular:karma';
+        test.options ??= {};
+        test.options.tsConfig = 'tsconfig.spec.json';
+        delete test.options.runner;
       });
       await updateJsonFile('tsconfig.json', (tsconfig) => {
         delete tsconfig.compilerOptions.esModuleInterop;
diff --git a/tests/legacy-cli/e2e/tests/basic/test.ts b/tests/legacy-cli/e2e/tests/basic/test.ts
index d9066946ae8e..50580581d442 100644
--- a/tests/legacy-cli/e2e/tests/basic/test.ts
+++ b/tests/legacy-cli/e2e/tests/basic/test.ts
@@ -1,5 +1,6 @@
 import { ng } from '../../utils/process';
 import { writeMultipleFiles } from '../../utils/fs';
+import { getGlobalVariable } from '../../utils/env';
 
 export default async function () {
   // make sure both --watch=false work
@@ -48,5 +49,11 @@ export default async function () {
       `,
   });
 
-  await ng('test', '--watch=false', '--karma-config=karma.conf.bis.js');
+  const isWebpack = !getGlobalVariable('argv')['esbuild'];
+
+  if (isWebpack) {
+    await ng('test', '--watch=false', '--karma-config=karma.conf.bis.js');
+  } else {
+    await ng('test', '--watch=false', '--runner-config=karma.conf.bis.js');
+  }
 }
diff --git a/tests/legacy-cli/e2e/tests/test/test-code-coverage-exclude.ts b/tests/legacy-cli/e2e/tests/test/test-code-coverage-exclude.ts
index 3533e6c8e9a9..808bcb59e2d9 100644
--- a/tests/legacy-cli/e2e/tests/test/test-code-coverage-exclude.ts
+++ b/tests/legacy-cli/e2e/tests/test/test-code-coverage-exclude.ts
@@ -1,10 +1,14 @@
+import { getGlobalVariable } from '../../utils/env';
 import { expectFileToExist, rimraf } from '../../utils/fs';
 import { silentNg } from '../../utils/process';
 import { expectToFail } from '../../utils/utils';
 
 export default async function () {
+  const isWebpack = !getGlobalVariable('argv')['esbuild'];
+  const coverageOptionName = isWebpack ? '--code-coverage' : '--coverage';
+
   // This test is already in build-angular, but that doesn't run on Windows.
-  await silentNg('test', '--no-watch', '--code-coverage');
+  await silentNg('test', '--no-watch', coverageOptionName);
   await expectFileToExist('coverage/test-project/app.ts.html');
   // Delete coverage directory
   await rimraf('coverage');
@@ -12,8 +16,8 @@ export default async function () {
   await silentNg(
     'test',
     '--no-watch',
-    '--code-coverage',
-    `--code-coverage-exclude='src/**/app.ts'`,
+    coverageOptionName,
+    `${coverageOptionName}-exclude='src/**/app.ts'`,
   );
 
   // Doesn't include excluded.
diff --git a/tests/legacy-cli/e2e/tests/test/test-environment.ts b/tests/legacy-cli/e2e/tests/test/test-environment.ts
index 1a4dadaa4317..1670cb246521 100644
--- a/tests/legacy-cli/e2e/tests/test/test-environment.ts
+++ b/tests/legacy-cli/e2e/tests/test/test-environment.ts
@@ -1,21 +1,23 @@
 import { ng } from '../../utils/process';
 import { writeFile, writeMultipleFiles } from '../../utils/fs';
 import { updateJsonFile } from '../../utils/project';
+import { getGlobalVariable } from '../../utils/env';
+
+export default async function () {
+  const isWebpack = !getGlobalVariable('argv')['esbuild'];
 
-export default function () {
   // Tests run in 'dev' environment by default.
-  return (
-    writeMultipleFiles({
-      'src/environment.prod.ts': `
+  await writeMultipleFiles({
+    'src/environment.prod.ts': `
       export const environment = {
         production: true
       };`,
-      'src/environment.ts': `
+    'src/environment.ts': `
       export const environment = {
         production: false
       };
       `,
-      'src/app/environment.spec.ts': `
+    'src/app/environment.spec.ts': `
       import { environment } from '../environment';
 
       describe('Test environment', () => {
@@ -24,29 +26,33 @@ export default function () {
         });
       });
     `,
-    })
-      .then(() => ng('test', '--watch=false'))
-      .then(() =>
-        updateJsonFile('angular.json', (configJson) => {
-          const appArchitect = configJson.projects['test-project'].architect;
-          appArchitect.test.configurations = {
-            production: {
-              fileReplacements: [
-                {
-                  replace: 'src/environment.ts',
-                  with: 'src/environment.prod.ts',
-                },
-              ],
-            },
-          };
-        }),
-      )
-
-      // Tests can run in different environment.
-      .then(() =>
-        writeFile(
-          'src/app/environment.spec.ts',
-          `
+  });
+
+  await ng('test', '--watch=false');
+
+  await updateJsonFile('angular.json', (configJson) => {
+    const appArchitect = configJson.projects['test-project'].architect;
+    appArchitect[isWebpack ? 'test' : 'build'].configurations = {
+      production: {
+        fileReplacements: [
+          {
+            replace: 'src/environment.ts',
+            with: 'src/environment.prod.ts',
+          },
+        ],
+      },
+    };
+    if (!isWebpack) {
+      appArchitect.test.options ??= {};
+      appArchitect.test.options.buildTarget = '::production';
+    }
+  });
+
+  // Tests can run in different environment.
+
+  await writeFile(
+    'src/app/environment.spec.ts',
+    `
       import { environment } from '../environment';
 
       describe('Test environment', () => {
@@ -55,8 +61,11 @@ export default function () {
         });
       });
     `,
-        ),
-      )
-      .then(() => ng('test', '--configuration=production', '--watch=false'))
   );
+
+  if (isWebpack) {
+    await ng('test', '--watch=false', '--configuration=production');
+  } else {
+    await ng('test', '--watch=false');
+  }
 }
diff --git a/tests/legacy-cli/e2e/tests/test/test-scripts.ts b/tests/legacy-cli/e2e/tests/test/test-scripts.ts
index acbcc66dc230..1537cdddf349 100644
--- a/tests/legacy-cli/e2e/tests/test/test-scripts.ts
+++ b/tests/legacy-cli/e2e/tests/test/test-scripts.ts
@@ -1,3 +1,4 @@
+import { getGlobalVariable } from '../../utils/env';
 import { writeMultipleFiles } from '../../utils/fs';
 import { ng } from '../../utils/process';
 import { updateJsonFile } from '../../utils/project';
@@ -60,9 +61,10 @@ export default async function () {
   // should fail because the global scripts were not added to scripts array
   await expectToFail(() => ng('test', '--watch=false'));
 
+  const isWebpack = !getGlobalVariable('argv')['esbuild'];
   await updateJsonFile('angular.json', (workspaceJson) => {
     const appArchitect = workspaceJson.projects['test-project'].architect;
-    appArchitect.test.options.scripts = [
+    appArchitect[isWebpack ? 'test' : 'build'].options.scripts = [
       { input: 'src/string-script.js' },
       { input: 'src/input-script.js' },
     ];
diff --git a/tests/legacy-cli/e2e/tests/test/test-sourcemap.ts b/tests/legacy-cli/e2e/tests/test/test-sourcemap.ts
index 9e2a8e3f36fa..6c1cf16cd7b3 100644
--- a/tests/legacy-cli/e2e/tests/test/test-sourcemap.ts
+++ b/tests/legacy-cli/e2e/tests/test/test-sourcemap.ts
@@ -1,10 +1,13 @@
 import assert from 'node:assert';
-import { getGlobalVariable } from '../../utils/env';
 import { writeFile } from '../../utils/fs';
 import { ng } from '../../utils/process';
 import { assertIsError } from '../../utils/utils';
+import { updateJsonFile } from '../../utils/project';
+import { getGlobalVariable } from '../../utils/env';
 
 export default async function () {
+  const isWebpack = !getGlobalVariable('argv')['esbuild'];
+
   await writeFile(
     'src/app/app.spec.ts',
     `
@@ -15,8 +18,16 @@ export default async function () {
   );
 
   // when sourcemaps are 'on' the stacktrace will point to the spec.ts file.
+  await updateJsonFile('angular.json', (configJson) => {
+    const appArchitect = configJson.projects['test-project'].architect;
+    if (isWebpack) {
+      appArchitect['test'].options.sourceMap = true;
+    } else {
+      appArchitect['build'].configurations.development.sourceMap = true;
+    }
+  });
   try {
-    await ng('test', '--no-watch', '--source-map');
+    await ng('test', '--no-watch');
     throw new Error('ng test should have failed.');
   } catch (error) {
     assertIsError(error);
@@ -25,8 +36,16 @@ export default async function () {
   }
 
   // when sourcemaps are 'off' the stacktrace won't point to the spec.ts file.
+  await updateJsonFile('angular.json', (configJson) => {
+    const appArchitect = configJson.projects['test-project'].architect;
+    if (isWebpack) {
+      appArchitect['test'].options.sourceMap = false;
+    } else {
+      appArchitect['build'].configurations.development.sourceMap = false;
+    }
+  });
   try {
-    await ng('test', '--no-watch', '--no-source-map');
+    await ng('test', '--no-watch');
     throw new Error('ng test should have failed.');
   } catch (error) {
     assertIsError(error);
diff --git a/tests/legacy-cli/e2e/utils/project.ts b/tests/legacy-cli/e2e/utils/project.ts
index ea764bb20314..c84b7fce8e1d 100644
--- a/tests/legacy-cli/e2e/utils/project.ts
+++ b/tests/legacy-cli/e2e/utils/project.ts
@@ -191,7 +191,11 @@ export async function useCIChrome(projectName: string, projectDir = ''): Promise
   return updateJsonFile('angular.json', (workspaceJson) => {
     const project = workspaceJson.projects[projectName];
     const appTargets = project.targets || project.architect;
-    appTargets.test.options.browsers = 'ChromeHeadlessNoSandbox';
+    if (appTargets.test.builder === '@angular/build:unit-test') {
+      appTargets.test.options.browsers = ['ChromeHeadlessNoSandbox'];
+    } else {
+      appTargets.test.options.browsers = 'ChromeHeadlessNoSandbox';
+    }
   });
 }