diff --git a/generators/base-application/generator.spec.ts b/generators/base-application/generator.spec.ts
index eeafed6384c6..545fc27285f9 100644
--- a/generators/base-application/generator.spec.ts
+++ b/generators/base-application/generator.spec.ts
@@ -24,7 +24,6 @@ import { snakeCase } from 'lodash-es';
 
 import EnvironmentBuilder from '../../cli/environment-builder.mjs';
 import Generator from './index.js';
-import type { BaseApplication } from '../base-application/types.js';
 import { defaultHelpers as helpers } from '../../testing/index.js';
 import { shouldSupportFeatures } from '../../test/support/tests.js';
 
@@ -318,7 +317,7 @@ describe(`generator - ${generator}`, () => {
     const writingEntities = esmocha.fn();
     const postWritingEntities = esmocha.fn();
 
-    class CustomGenerator extends Generator<BaseApplication> {
+    class CustomGenerator extends Generator {
       async beforeQueue() {
         await this.dependsOnJHipster('bootstrap-application');
       }
diff --git a/generators/client/generator-needles.spec.ts b/generators/client/generator-needles.spec.ts
index c4bce5b6bf42..e1d1007c535b 100644
--- a/generators/client/generator-needles.spec.ts
+++ b/generators/client/generator-needles.spec.ts
@@ -15,7 +15,7 @@ const mockBlueprintSubGen: any = class extends ClientGenerator {
   get [ClientGenerator.POST_WRITING]() {
     return this.asPostWritingTaskGroup({
       webpackPhase({ source }) {
-        source.addWebpackConfig({ config: '{devServer:{}}' });
+        source!.addWebpackConfig!({ config: '{devServer:{}}' });
       },
     });
   }
diff --git a/generators/client/needle-client.spec.ts b/generators/client/needle-client.spec.ts
index f2e55eb41b58..a5cb07295786 100644
--- a/generators/client/needle-client.spec.ts
+++ b/generators/client/needle-client.spec.ts
@@ -19,7 +19,7 @@ const mockBlueprintSubGen: any = class extends ClientGenerator {
     return this.asPostWritingTaskGroup({
       // @ts-ignore
       async additionalResource({ source }) {
-        source.addExternalResourceToRoot({
+        source!.addExternalResourceToRoot!({
           resource: '<link rel="stylesheet" href="content/css/my.css">',
           comment: 'Comment added by JHipster API',
         });
@@ -38,7 +38,7 @@ describe('needle API Client: JHipster client generator with blueprint', () => {
       .withOptions({
         blueprint: 'myblueprint',
       })
-      .withGenerators([[mockBlueprintSubGen, 'jhipster-myblueprint:client']]);
+      .withGenerators([[mockBlueprintSubGen, { namespace: 'jhipster-myblueprint:client' }]]);
   });
 
   it('Assert index.html contain the comment and the resource added', () => {
diff --git a/generators/entity/database-changelog.spec.ts b/generators/entity/database-changelog.spec.ts
index 367d5377415b..d2d06a1491c0 100644
--- a/generators/entity/database-changelog.spec.ts
+++ b/generators/entity/database-changelog.spec.ts
@@ -21,7 +21,7 @@ describe('generator - entity database changelogs', () => {
       before(async () => {
         await helpers
           .run(getGenerator('entity'))
-          .withGenerators([[MockedLanguagesGenerator, 'jhipster:languages']])
+          .withGenerators([[MockedLanguagesGenerator, { namespace: 'jhipster:languages' }]])
           .withJHipsterConfig({ databaseType: 'cassandra' }, [entityFoo])
           .withArguments(['Foo'])
           .withOptions({ regenerate: true, force: true, ignoreNeedlesError: true });
@@ -35,7 +35,7 @@ describe('generator - entity database changelogs', () => {
       before(async () => {
         await helpers
           .run(getGenerator('entity'))
-          .withGenerators([[MockedLanguagesGenerator, 'jhipster:languages']])
+          .withGenerators([[MockedLanguagesGenerator, { namespace: 'jhipster:languages' }]])
           .withJHipsterConfig({ applicationType: 'gateway' }, [
             { ...entityFoo, microservicePath: 'microservice1', microserviceName: 'microservice1' },
           ])
diff --git a/generators/entity/single-entity.spec.ts b/generators/entity/single-entity.spec.ts
index 920bd7296ceb..60bb4cdbe71c 100644
--- a/generators/entity/single-entity.spec.ts
+++ b/generators/entity/single-entity.spec.ts
@@ -23,7 +23,7 @@ describe('generator - entity --single-entity', () => {
       before(async () => {
         await helpers
           .runJHipster(GENERATOR_ENTITY)
-          .withGenerators([[MockedLanguagesGenerator, 'jhipster:languages']])
+          .withGenerators([[MockedLanguagesGenerator, { namespace: 'jhipster:languages' }]])
           .withJHipsterConfig({}, [entityFoo, entityBar])
           .withArguments(['Foo'])
           .withOptions({ ignoreNeedlesError: true, regenerate: true, force: true, singleEntity: true })
@@ -56,7 +56,7 @@ describe('generator - entity --single-entity', () => {
       before(async () => {
         runResult = await helpers
           .runJHipster(GENERATOR_ENTITY)
-          .withGenerators([[MockedLanguagesGenerator, 'jhipster:languages']])
+          .withGenerators([[MockedLanguagesGenerator, { namespace: 'jhipster:languages' }]])
           .withJHipsterConfig({ databaseType: 'cassandra' }, [entityFoo, entityBar])
           .withArguments(['Foo'])
           .withOptions({ ignoreNeedlesError: true, regenerate: true, force: true, singleEntity: true });
diff --git a/generators/gradle/needles.spec.ts b/generators/gradle/needles.spec.ts
index 48506c23b014..9c4b112d7f56 100644
--- a/generators/gradle/needles.spec.ts
+++ b/generators/gradle/needles.spec.ts
@@ -49,7 +49,7 @@ describe('needle API server gradle: JHipster server generator with blueprint', (
         clientFramework: 'no',
         buildTool: 'gradle',
       })
-      .withGenerators([[mockBlueprintSubGen, 'jhipster-myblueprint:server']]);
+      .withGenerators([[mockBlueprintSubGen, { namespace: 'jhipster-myblueprint:server' }]]);
   });
 
   it('Assert gradle.properties has the property added', () => {
diff --git a/generators/java/support/checks/check-java.spec.ts b/generators/java/support/checks/check-java.spec.ts
index 45eb8946aa3e..8afb25ab890e 100644
--- a/generators/java/support/checks/check-java.spec.ts
+++ b/generators/java/support/checks/check-java.spec.ts
@@ -1,10 +1,11 @@
 import { after, before, it, describe, expect, resetAllMocks, esmocha } from 'esmocha';
-import { ExecaSyncReturnValue } from 'execa';
+import { SyncResult } from 'execa';
 import quibble from 'quibble';
 
 const execa = { execa: esmocha.fn(), execaSync: esmocha.fn(), execaCommandSync: esmocha.fn(), execaCommand: esmocha.fn() };
 
-const baseResult: ExecaSyncReturnValue<string> = {
+const baseResult: SyncResult = {
+  cwd: '',
   command: 'java',
   escapedCommand: 'java',
   exitCode: 0,
@@ -12,8 +13,7 @@ const baseResult: ExecaSyncReturnValue<string> = {
   stderr: '',
   failed: false,
   timedOut: false,
-  killed: false,
-};
+} as any;
 
 describe('generator - server - checkJava', () => {
   before(async () => {
@@ -34,7 +34,7 @@ describe('generator - server - checkJava', () => {
     before(async () => {
       execa.execaCommandSync.mockReturnValue({ ...baseResult, stderr } as any);
       const { default: checkJava } = await import('./check-java.js');
-      result = checkJava();
+      result = checkJava([]);
     });
 
     it('should return info and javaVersion', async () => {
@@ -53,7 +53,7 @@ describe('generator - server - checkJava', () => {
     before(async () => {
       execa.execaCommandSync.mockReturnValue({ ...baseResult, exitCode, stderr } as any);
       const { default: checkJava } = await import('./check-java.js');
-      result = checkJava();
+      result = checkJava([]);
     });
 
     it('should return error', async () => {
@@ -69,7 +69,7 @@ describe('generator - server - checkJava', () => {
         throw new Error('foo');
       });
       const { default: checkJava } = await import('./check-java.js');
-      result = checkJava();
+      result = checkJava([]);
     });
 
     it('should return error', async () => {
diff --git a/generators/java/support/doc.ts b/generators/java/support/doc.ts
index 6a754aa0046b..3dd5ba55c95c 100644
--- a/generators/java/support/doc.ts
+++ b/generators/java/support/doc.ts
@@ -45,7 +45,7 @@ export const formatDocAsJavaDoc = (text: string, indentSize = 0): string => {
   return rows.join('\n');
 };
 
-export const formatDocAsApiDescription = (text: string): string => {
+export const formatDocAsApiDescription = (text?: string): string | undefined => {
   if (!text) {
     return text;
   }
diff --git a/generators/liquibase/needles.spec.ts b/generators/liquibase/needles.spec.ts
index 88477eba0e83..9dc5bf36dbd1 100644
--- a/generators/liquibase/needles.spec.ts
+++ b/generators/liquibase/needles.spec.ts
@@ -45,7 +45,7 @@ describe('generator - liquibase - needles', () => {
       .withOptions({
         skipPriorities: ['writing'],
       })
-      .withGenerators([[mockBlueprintSubGen, 'jhipster-myblueprint:liquibase']]);
+      .withGenerators([[mockBlueprintSubGen, { namespace: 'jhipster-myblueprint:liquibase' }]]);
   });
 
   it('Assert changelog is added to master.xml', () => {
diff --git a/generators/maven/generator.spec.ts b/generators/maven/generator.spec.ts
index 10b8b9eb8aa7..e59357f428c1 100644
--- a/generators/maven/generator.spec.ts
+++ b/generators/maven/generator.spec.ts
@@ -94,7 +94,7 @@ describe(`generator - ${generator}`, () => {
                 });
               }
             },
-            'jhipster-blueprint:maven',
+            { namespace: 'jhipster-blueprint:maven' },
           ],
         ]);
     });
diff --git a/generators/maven/needles.spec.ts b/generators/maven/needles.spec.ts
index 84d73399a601..ec026506edb9 100644
--- a/generators/maven/needles.spec.ts
+++ b/generators/maven/needles.spec.ts
@@ -13,7 +13,7 @@ class mockBlueprintSubGen extends BaseApplicationGenerator {
   get [BaseApplicationGenerator.POST_WRITING]() {
     return this.asPostWritingTaskGroup({
       mavenStep({ source }) {
-        const inProfile = this.options.profile;
+        const inProfile = (this.options as any).profile;
         function asItemOrArray<T>(item: T): T | T[] {
           return inProfile ? [item] : item;
         }
diff --git a/generators/server/options/database-migration.spec.ts b/generators/server/options/database-migration.spec.ts
index 42210808ab6b..15e85a9bf949 100644
--- a/generators/server/options/database-migration.spec.ts
+++ b/generators/server/options/database-migration.spec.ts
@@ -4,7 +4,7 @@ import { DATABASE_MIGRATION as optionName } from './index.js';
 import optionDefinition from './database-migration.js';
 
 describe(`generators - server - jdl - ${optionName}`, () => {
-  optionDefinition.knownChoices.forEach(optionValue => {
+  optionDefinition.knownChoices!.forEach(optionValue => {
     describe(`with ${optionValue} value`, () => {
       let state: ImportState;
 
diff --git a/generators/server/options/message-broker.spec.ts b/generators/server/options/message-broker.spec.ts
index 7c9e2b3fb57e..cab5f7370573 100644
--- a/generators/server/options/message-broker.spec.ts
+++ b/generators/server/options/message-broker.spec.ts
@@ -4,7 +4,7 @@ import { MESSAGE_BROKER } from './index.js';
 import optionDefinition from './message-broker.js';
 
 describe('generators - server - jdl - messageBroker', () => {
-  optionDefinition.knownChoices.forEach(optionValue => {
+  optionDefinition.knownChoices!.forEach(optionValue => {
     describe(`with ${optionValue} value`, () => {
       let state: ImportState;
 
diff --git a/generators/server/support/needles.spec.ts b/generators/server/support/needles.spec.ts
index 12e165ffa13e..b8653225d6fd 100644
--- a/generators/server/support/needles.spec.ts
+++ b/generators/server/support/needles.spec.ts
@@ -17,15 +17,15 @@
  * limitations under the License.
  */
 import { before, it, describe, expect } from 'esmocha';
-import { defaultHelpers as helpers } from '../../../testing/index.js';
+import { defaultHelpers as helpers, runResult } from '../../../testing/index.js';
 import { GENERATOR_SPRING_BOOT } from '../../generator-list.js';
 import { insertContentIntoApplicationProperties } from './needles.js';
+import type { SpringBootApplication } from '../types.js';
 
 describe('generator - server - support - needles', () => {
   describe('generated project', () => {
-    let runResult;
     before(async () => {
-      runResult = await helpers
+      await helpers
         .runJHipster(GENERATOR_SPRING_BOOT)
         .withMockedGenerators(['jhipster:common', 'jhipster:languages', 'jhipster:liquibase']);
     });
@@ -36,7 +36,7 @@ describe('generator - server - support - needles', () => {
 
     describe('insertContentIntoApplicationProperties needle', () => {
       it('with a non existing needle', () => {
-        const application = runResult.generator.sharedData.getApplication();
+        const application: SpringBootApplication = runResult.generator.sharedData.getApplication();
         expect(() => insertContentIntoApplicationProperties.call(runResult.generator, application, { foo: 'foo' })).toThrow(
           /Missing required jhipster-needle application-properties-foo not found at/,
         );
diff --git a/generators/upgrade/upgrade.spec.ts b/generators/upgrade/upgrade.spec.ts
index b17717fb25c9..8061a0ed7bc4 100644
--- a/generators/upgrade/upgrade.spec.ts
+++ b/generators/upgrade/upgrade.spec.ts
@@ -24,7 +24,11 @@ describe('generator - upgrade', function () {
           baseName: 'upgradeTest',
         })
         .withOptions({ useVersionPlaceholders: false });
-      await runResult.create(getGenerator(GENERATOR_UPGRADE)).withSpawnMock().withOptions({ useVersionPlaceholders: false }).run();
+      await runResult
+        .create(getGenerator(GENERATOR_UPGRADE))
+        .withSpawnMock()
+        .withOptions({ useVersionPlaceholders: false } as any)
+        .run();
     });
 
     it('generated git commits to match snapshot', () => {
diff --git a/testing/helpers.ts b/testing/helpers.ts
index 187f2e6c9d4e..a1f06d385692 100644
--- a/testing/helpers.ts
+++ b/testing/helpers.ts
@@ -15,12 +15,13 @@ import BaseGenerator from '../generators/base/index.js';
 import type { JHipsterGeneratorOptions } from '../generators/base/api.js';
 import { getPackageRoot, isDistFolder } from '../lib/index.js';
 import type { JSONEntity } from '../jdl/converters/types.js';
+import CoreGenerator from '../generators/base-core/generator.js';
 
 type BaseEntity = { name: string } & JSONEntity;
 type GeneratorTestType = YeomanGenerator<JHipsterGeneratorOptions>;
 type GeneratorTestOptions = JHipsterGeneratorOptions;
 
-type JHipsterRunResult<GeneratorType extends YeomanGenerator = YeomanGenerator> = RunResult<GeneratorType> & {
+type JHipsterRunResult<GeneratorType extends CoreGenerator = CoreGenerator> = RunResult<GeneratorType> & {
   /**
    * First argument of mocked source calls.
    */
diff --git a/tsconfig.spec.json b/tsconfig.spec.json
index 68e758248cdc..78ff50dcc4f4 100644
--- a/tsconfig.spec.json
+++ b/tsconfig.spec.json
@@ -1,6 +1,15 @@
 {
   "include": ["cli/**/*", "generators/**/*", "jdl/**/*", "lib/**/*", "testing/**/*"],
-  "exclude": ["generators/**/*.spec.*"],
+  "exclude": [
+    "generators/base-application/*.spec.*",
+    "generators/base-core/*.spec.*",
+    "generators/base/**/*.spec.*",
+    "generators/base-application/*.spec.*",
+    "generators/bootstrap-application/*.spec.*",
+    "generators/bootstrap-application-base/*.spec.*",
+    "generators/java/generators/domain/*.spec.*",
+    "generators/server/support/needles.spec.ts"
+  ],
   "extends": "./tsconfig.json",
   "compilerOptions": {
     "noEmit": true,