diff --git a/packages/angular_devkit/architect/builders/all-of.ts b/packages/angular_devkit/architect/builders/all-of.ts
index 357d4d4882c5..aebe3a2d58cc 100644
--- a/packages/angular_devkit/architect/builders/all-of.ts
+++ b/packages/angular_devkit/architect/builders/all-of.ts
@@ -6,12 +6,11 @@
  * found in the LICENSE file at https://angular.dev/license
  */
 
-import { json } from '@angular-devkit/core';
 import { EMPTY, from, map, mergeMap, of } from 'rxjs';
-import { BuilderOutput, BuilderRun, createBuilder } from '../src';
+import { Builder, BuilderOutput, BuilderRun, createBuilder } from '../src';
 import { Schema as OperatorSchema } from './operator-schema';
 
-export default createBuilder<json.JsonObject & OperatorSchema>((options, context) => {
+const builder: Builder<OperatorSchema> = createBuilder((options, context) => {
   const allRuns: Promise<[number, BuilderRun]>[] = [];
 
   context.reportProgress(
@@ -66,3 +65,5 @@ export default createBuilder<json.JsonObject & OperatorSchema>((options, context
     }),
   );
 });
+
+export default builder;
diff --git a/packages/angular_devkit/architect/builders/concat.ts b/packages/angular_devkit/architect/builders/concat.ts
index c07d9f3ef74a..00bf17871f4e 100644
--- a/packages/angular_devkit/architect/builders/concat.ts
+++ b/packages/angular_devkit/architect/builders/concat.ts
@@ -6,12 +6,11 @@
  * found in the LICENSE file at https://angular.dev/license
  */
 
-import { json } from '@angular-devkit/core';
 import { concatMap, first, from, last, map, of, switchMap } from 'rxjs';
-import { BuilderOutput, BuilderRun, createBuilder } from '../src';
+import { Builder, BuilderOutput, BuilderRun, createBuilder } from '../src';
 import { Schema as OperatorSchema } from './operator-schema';
 
-export default createBuilder<json.JsonObject & OperatorSchema>((options, context) => {
+const builder: Builder<OperatorSchema> = createBuilder((options, context) => {
   const allRuns: (() => Promise<BuilderRun>)[] = [];
 
   context.reportProgress(
@@ -61,3 +60,5 @@ export default createBuilder<json.JsonObject & OperatorSchema>((options, context
     last(),
   );
 });
+
+export default builder;
diff --git a/packages/angular_devkit/architect/builders/false.ts b/packages/angular_devkit/architect/builders/false.ts
index 59fd3317d00a..3a3b8e4c470f 100644
--- a/packages/angular_devkit/architect/builders/false.ts
+++ b/packages/angular_devkit/architect/builders/false.ts
@@ -6,9 +6,11 @@
  * found in the LICENSE file at https://angular.dev/license
  */
 
-import { createBuilder } from '../src';
+import { type Builder, createBuilder } from '../src';
 
-export default createBuilder(() => ({
+const builder: Builder<{}> = createBuilder(() => ({
   success: false,
   error: 'False builder always errors.',
 }));
+
+export default builder;
diff --git a/packages/angular_devkit/architect/builders/true.ts b/packages/angular_devkit/architect/builders/true.ts
index 83f477c86d92..52f1d0f0c857 100644
--- a/packages/angular_devkit/architect/builders/true.ts
+++ b/packages/angular_devkit/architect/builders/true.ts
@@ -6,6 +6,8 @@
  * found in the LICENSE file at https://angular.dev/license
  */
 
-import { createBuilder } from '../src';
+import { type Builder, createBuilder } from '../src';
 
-export default createBuilder(() => ({ success: true }));
+const builder: Builder<{}> = createBuilder(() => ({ success: true }));
+
+export default builder;
diff --git a/packages/angular_devkit/architect/node/node-modules-architect-host.ts b/packages/angular_devkit/architect/node/node-modules-architect-host.ts
index 6319ab638360..554f85be14ad 100644
--- a/packages/angular_devkit/architect/node/node-modules-architect-host.ts
+++ b/packages/angular_devkit/architect/node/node-modules-architect-host.ts
@@ -121,7 +121,7 @@ export class WorkspaceNodeModulesArchitectHost implements ArchitectHost<NodeModu
     }
   }
 
-  async getBuilderNameForTarget(target: Target) {
+  async getBuilderNameForTarget(target: Target): Promise<string> {
     return this.workspaceHost.getBuilderName(target.project, target.target);
   }
 
@@ -134,7 +134,7 @@ export class WorkspaceNodeModulesArchitectHost implements ArchitectHost<NodeModu
    */
   resolveBuilder(
     builderStr: string,
-    basePath = this._root,
+    basePath: string = this._root,
     seenBuilders?: Set<string>,
   ): Promise<NodeModulesBuilderInfo> {
     if (seenBuilders?.has(builderStr)) {
@@ -228,11 +228,11 @@ export class WorkspaceNodeModulesArchitectHost implements ArchitectHost<NodeModu
     });
   }
 
-  async getCurrentDirectory() {
+  async getCurrentDirectory(): Promise<string> {
     return process.cwd();
   }
 
-  async getWorkspaceRoot() {
+  async getWorkspaceRoot(): Promise<string> {
     return this._root;
   }
 
diff --git a/packages/angular_devkit/architect/src/architect.ts b/packages/angular_devkit/architect/src/architect.ts
index 6dbf97cb5179..89c318b30a06 100644
--- a/packages/angular_devkit/architect/src/architect.ts
+++ b/packages/angular_devkit/architect/src/architect.ts
@@ -364,7 +364,7 @@ export class Architect {
     this._scheduler = new SimpleScheduler(jobRegistry, registry);
   }
 
-  has(name: JobName) {
+  has(name: JobName): Observable<boolean> {
     return this._scheduler.has(name);
   }
 
diff --git a/packages/angular_devkit/architect/src/internal.ts b/packages/angular_devkit/architect/src/internal.ts
index 8f8154a0bc4d..3007d8867a28 100644
--- a/packages/angular_devkit/architect/src/internal.ts
+++ b/packages/angular_devkit/architect/src/internal.ts
@@ -19,7 +19,7 @@ import { JobDescription, JobHandler } from './jobs';
  * Using Symbol.for() as it's a global registry that's the same for all installations of
  * Architect (if some libraries depends directly on architect instead of sharing the files).
  */
-export const BuilderSymbol = Symbol.for('@angular-devkit/architect:builder');
+export const BuilderSymbol: unique symbol = Symbol.for('@angular-devkit/architect:builder');
 
 /**
  * BuilderVersionSymbol used for knowing which version of the library createBuilder() came from.
@@ -27,7 +27,7 @@ export const BuilderSymbol = Symbol.for('@angular-devkit/architect:builder');
  * Using Symbol.for() as it's a global registry that's the same for all installations of
  * Architect (if some libraries depends directly on architect instead of sharing the files).
  */
-export const BuilderVersionSymbol = Symbol.for('@angular-devkit/architect:version');
+export const BuilderVersionSymbol: unique symbol = Symbol.for('@angular-devkit/architect:version');
 
 /**
  * A Specialization of the JobHandler type. This exposes BuilderDescription as the job description
diff --git a/packages/angular_devkit/architect/src/jobs/fallback-registry.ts b/packages/angular_devkit/architect/src/jobs/fallback-registry.ts
index e3a0ee0ac57a..c4d5dfb5cfe0 100644
--- a/packages/angular_devkit/architect/src/jobs/fallback-registry.ts
+++ b/packages/angular_devkit/architect/src/jobs/fallback-registry.ts
@@ -27,7 +27,7 @@ export class FallbackRegistry<
     >[] = [],
   ) {}
 
-  addFallback(registry: Registry) {
+  addFallback(registry: Registry): void {
     this._fallbacks.push(registry);
   }
 
diff --git a/packages/angular_devkit/architect/src/jobs/simple-scheduler.ts b/packages/angular_devkit/architect/src/jobs/simple-scheduler.ts
index 8dacbbe687f8..f5ec59b4f364 100644
--- a/packages/angular_devkit/architect/src/jobs/simple-scheduler.ts
+++ b/packages/angular_devkit/architect/src/jobs/simple-scheduler.ts
@@ -185,7 +185,7 @@ export class SimpleScheduler<
    * @param name The name of the job.
    * @returns A description, or null if the job is not registered.
    */
-  getDescription(name: JobName) {
+  getDescription(name: JobName): Observable<JobDescription | null> {
     return concat(
       this._getInternalDescription(name).pipe(map((x) => x && x.jobDescription)),
       of(null),
@@ -197,7 +197,7 @@ export class SimpleScheduler<
    * @param name The name of the job.
    * @returns True if the job exists, false otherwise.
    */
-  has(name: JobName) {
+  has(name: JobName): Observable<boolean> {
     return this.getDescription(name).pipe(map((x) => x !== null));
   }
 
@@ -209,7 +209,7 @@ export class SimpleScheduler<
    *
    * Jobs already running are NOT paused. This is pausing the scheduler only.
    */
-  pause() {
+  pause(): () => void {
     let called = false;
     this._pauseCounter++;
 
diff --git a/packages/angular_devkit/architect/testing/test-project-host.ts b/packages/angular_devkit/architect/testing/test-project-host.ts
index ca7aa4fc84be..4af99462db08 100644
--- a/packages/angular_devkit/architect/testing/test-project-host.ts
+++ b/packages/angular_devkit/architect/testing/test-project-host.ts
@@ -126,7 +126,7 @@ export class TestProjectHost extends NodeJsSyncHost {
     });
   }
 
-  replaceInFile(path: string, match: RegExp | string, replacement: string) {
+  replaceInFile(path: string, match: RegExp | string, replacement: string): void {
     const content = virtualFs.fileBufferToString(this.scopedSync().read(normalize(path)));
     this.scopedSync().write(
       normalize(path),
@@ -134,7 +134,7 @@ export class TestProjectHost extends NodeJsSyncHost {
     );
   }
 
-  appendToFile(path: string, str: string) {
+  appendToFile(path: string, str: string): void {
     const content = virtualFs.fileBufferToString(this.scopedSync().read(normalize(path)));
     this.scopedSync().write(normalize(path), virtualFs.stringToFileBuffer(content.concat(str)));
   }
@@ -147,7 +147,7 @@ export class TestProjectHost extends NodeJsSyncHost {
     return fileName || undefined;
   }
 
-  copyFile(from: string, to: string) {
+  copyFile(from: string, to: string): void {
     const content = this.scopedSync().read(normalize(from));
     this.scopedSync().write(normalize(to), content);
   }
diff --git a/packages/angular_devkit/architect/testing/testing-architect-host.ts b/packages/angular_devkit/architect/testing/testing-architect-host.ts
index 0b3eeb36ba77..2f61d8f69d9d 100644
--- a/packages/angular_devkit/architect/testing/testing-architect-host.ts
+++ b/packages/angular_devkit/architect/testing/testing-architect-host.ts
@@ -23,7 +23,7 @@ export class TestingArchitectHost implements ArchitectHost {
    */
   constructor(
     public workspaceRoot = '',
-    public currentDirectory = workspaceRoot,
+    public currentDirectory: string = workspaceRoot,
     private _backendHost: ArchitectHost | null = null,
   ) {}
 
@@ -32,11 +32,11 @@ export class TestingArchitectHost implements ArchitectHost {
     builder: Builder,
     description = 'Testing only builder.',
     optionSchema: json.schema.JsonSchema = { type: 'object' },
-  ) {
+  ): void {
     this._builderImportMap.set(builderName, builder);
     this._builderMap.set(builderName, { builderName, description, optionSchema });
   }
-  async addBuilderFromPackage(packageName: string) {
+  async addBuilderFromPackage(packageName: string): Promise<void> {
     const packageJson = await import(packageName + '/package.json');
     if (!('builders' in packageJson)) {
       throw new Error('Invalid package.json, builders key not found.');
@@ -64,7 +64,7 @@ export class TestingArchitectHost implements ArchitectHost {
       this.addBuilder(`${packageJson.name}:${builderName}`, handler, b.description, optionsSchema);
     }
   }
-  addTarget(target: Target, builderName: string, options: json.JsonObject = {}) {
+  addTarget(target: Target, builderName: string, options: json.JsonObject = {}): void {
     this._targetMap.set(targetStringFromTarget(target), { builderName, options });
   }