angular · leonsenft · Apr 22, 2026 · Apr 14, 2026
diff --git a/goldens/public-api/compiler-cli/error_code.api.md b/goldens/public-api/compiler-cli/error_code.api.md
@@ -109,6 +109,7 @@ export enum ErrorCode {
     PIPE_MISSING_NAME = 2002,
     SCHEMA_INVALID_ATTRIBUTE = 8002,
     SCHEMA_INVALID_ELEMENT = 8001,
+    SERVICE_CONSTRUCTOR_DI = 2028,
     SKIP_HYDRATION_NOT_STATIC = 8108,
     SPLIT_TWO_WAY_BINDING = 8007,
     SUFFIX_NOT_SUPPORTED = 8106,

diff --git a/goldens/public-api/core/index.api.md b/goldens/public-api/core/index.api.md
@@ -1764,6 +1764,27 @@ export interface SelfDecorator {
     new (): Self;
 }
 
+// @public
+export interface Service {
+    autoProvided?: boolean;
+    factory?: () => unknown;
+}
+
+// @public
+export const Service: ServiceDecorator;
+
+// @public
+export interface ServiceDecorator {
+    (): TypeDecorator;
+    (options?: {
+        autoProvided: false;
+    }): TypeDecorator;
+    (options?: {
+        autoProvided?: true;
+        factory?: () => unknown;
+    }): TypeDecorator;
+}
+
 // @public
 export function setTestabilityGetter(getter: GetTestability): void;
 

diff --git a/packages/compiler-cli/linker/src/file_linker/partial_linkers/partial_linker_selector.ts b/packages/compiler-cli/linker/src/file_linker/partial_linkers/partial_linker_selector.ts
@@ -23,6 +23,7 @@ import {PartialNgModuleLinkerVersion1} from './partial_ng_module_linker_1';
 import {PartialPipeLinkerVersion1} from './partial_pipe_linker_1';
 import {PLACEHOLDER_VERSION} from './util';
 import {AbsoluteFsPath} from '../../../../src/ngtsc/file_system/src/types';
+import {PartialServiceLinkerVersion1} from './partial_service_linker_1';
 
 export const ɵɵngDeclareDirective = 'ɵɵngDeclareDirective';
 export const ɵɵngDeclareClassMetadata = 'ɵɵngDeclareClassMetadata';
@@ -33,6 +34,7 @@ export const ɵɵngDeclareInjector = 'ɵɵngDeclareInjector';
 export const ɵɵngDeclareNgModule = 'ɵɵngDeclareNgModule';
 export const ɵɵngDeclarePipe = 'ɵɵngDeclarePipe';
 export const ɵɵngDeclareClassMetadataAsync = 'ɵɵngDeclareClassMetadataAsync';
+export const ɵɵngDeclareService = 'ɵɵngDeclareService';
 export const declarationFunctions = [
   ɵɵngDeclareDirective,
   ɵɵngDeclareClassMetadata,
@@ -43,6 +45,7 @@ export const declarationFunctions = [
   ɵɵngDeclareNgModule,
   ɵɵngDeclarePipe,
   ɵɵngDeclareClassMetadataAsync,
+  ɵɵngDeclareService,
 ];
 
 export interface LinkerRange<TExpression> {
@@ -119,6 +122,9 @@ export function createLinkerMap<TStatement, TExpression, TType>(
   linkers.set(ɵɵngDeclarePipe, [
     {range: LATEST_VERSION_RANGE, linker: new PartialPipeLinkerVersion1()},
   ]);
+  linkers.set(ɵɵngDeclareService, [
+    {range: LATEST_VERSION_RANGE, linker: new PartialServiceLinkerVersion1()},
+  ]);
 
   return linkers;
 }

diff --git a/packages/compiler-cli/linker/src/file_linker/partial_linkers/partial_service_linker_1.ts b/packages/compiler-cli/linker/src/file_linker/partial_linkers/partial_service_linker_1.ts
@@ -0,0 +1,59 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.dev/license
+ */
+import {
+  compileService,
+  ConstantPool,
+  R3DeclareServiceMetadata,
+  R3PartialDeclaration,
+  R3ServiceMetadata,
+} from '@angular/compiler';
+
+import {AstObject} from '../../ast/ast_value';
+import {FatalLinkerError} from '../../fatal_linker_error';
+
+import {LinkedDefinition, PartialLinker} from './partial_linker';
+import {wrapReference} from './util';
+
+/**
+ * A `PartialLinker` that is designed to process `ɵɵngDeclareService()` call expressions.
+ */
+export class PartialServiceLinkerVersion1<TExpression> implements PartialLinker<TExpression> {
+  linkPartialDeclaration(
+    constantPool: ConstantPool,
+    metaObj: AstObject<R3PartialDeclaration, TExpression>,
+  ): LinkedDefinition {
+    const meta = toR3ServiceMeta(metaObj);
+    return compileService(meta, /* resolveForwardRefs */ false);
+  }
+}
+
+/**
+ * Derives the `R3ServiceMetadata` structure from the AST object.
+ */
+export function toR3ServiceMeta<TExpression>(
+  metaObj: AstObject<R3DeclareServiceMetadata, TExpression>,
+): R3ServiceMetadata {
+  const typeExpr = metaObj.getValue('type');
+  const typeName = typeExpr.getSymbolName();
+  if (typeName === null) {
+    throw new FatalLinkerError(
+      typeExpr.expression,
+      'Unsupported type, its name could not be determined',
+    );
+  }
+
+  const meta: R3ServiceMetadata = {
+    name: typeName,
+    type: wrapReference(typeExpr.getOpaque()),
+    typeArgumentCount: 0,
+    autoProvided: metaObj.has('autoProvided') ? metaObj.getBoolean('autoProvided') : undefined,
+    factory: metaObj.has('factory') ? metaObj.getOpaque('factory') : undefined,
+  };
+
+  return meta;
+}