diff --git a/packages/compiler-cli/ngcc/src/file_system/node_js_file_system.ts b/packages/compiler-cli/ngcc/src/file_system/node_js_file_system.ts
index 7f821c3986..8f4e7c797c 100644
--- a/packages/compiler-cli/ngcc/src/file_system/node_js_file_system.ts
+++ b/packages/compiler-cli/ngcc/src/file_system/node_js_file_system.ts
@@ -23,7 +23,7 @@ export class NodeJSFileSystem implements FileSystem {
   readdir(path: AbsoluteFsPath): PathSegment[] { return fs.readdirSync(path) as PathSegment[]; }
   lstat(path: AbsoluteFsPath): fs.Stats { return fs.lstatSync(path); }
   stat(path: AbsoluteFsPath): fs.Stats { return fs.statSync(path); }
-  pwd() { return AbsoluteFsPath.fromUnchecked(process.cwd()); }
+  pwd() { return AbsoluteFsPath.from(process.cwd()); }
   copyFile(from: AbsoluteFsPath, to: AbsoluteFsPath): void { cp(from, to); }
   moveFile(from: AbsoluteFsPath, to: AbsoluteFsPath): void { mv(from, to); }
   ensureDir(path: AbsoluteFsPath): void { mkdir('-p', path); }
diff --git a/packages/compiler-cli/ngcc/src/packages/entry_point_finder.ts b/packages/compiler-cli/ngcc/src/packages/entry_point_finder.ts
index f739669480..d1546a7466 100644
--- a/packages/compiler-cli/ngcc/src/packages/entry_point_finder.ts
+++ b/packages/compiler-cli/ngcc/src/packages/entry_point_finder.ts
@@ -92,7 +92,7 @@ export class EntryPointFinder {
             entryPoints.push(...this.getEntryPointsForPackage(packagePath));
 
             // Also check for any nested node_modules in this package
-            const nestedNodeModulesPath = AbsoluteFsPath.resolve(packagePath, 'node_modules');
+            const nestedNodeModulesPath = AbsoluteFsPath.join(packagePath, 'node_modules');
             if (this.fs.exists(nestedNodeModulesPath)) {
               entryPoints.push(...this.walkDirectoryForEntryPoints(nestedNodeModulesPath));
             }
diff --git a/packages/compiler-cli/ngcc/test/integration/ngcc_spec.ts b/packages/compiler-cli/ngcc/test/integration/ngcc_spec.ts
index f8c9023005..95e33310f3 100644
--- a/packages/compiler-cli/ngcc/test/integration/ngcc_spec.ts
+++ b/packages/compiler-cli/ngcc/test/integration/ngcc_spec.ts
@@ -7,8 +7,9 @@
  */
 
 import {AbsoluteFsPath} from '@angular/compiler-cli/src/ngtsc/path';
-import {existsSync, readFileSync, readdirSync, statSync, writeFileSync} from 'fs';
+import {existsSync, readFileSync, readdirSync, statSync, symlinkSync} from 'fs';
 import * as mockFs from 'mock-fs';
+import * as path from 'path';
 
 import {getAngularPackagesFromRunfiles, resolveNpmTreeArtifact} from '../../../test/runfile_helpers';
 import {NodeJSFileSystem} from '../../src/file_system/node_js_file_system';
@@ -333,10 +334,15 @@ describe('ngcc main()', () => {
 
 
 function createMockFileSystem() {
+  const typeScriptPath = path.join(process.env.RUNFILES !, 'typescript');
+  if (!existsSync(typeScriptPath)) {
+    symlinkSync(resolveNpmTreeArtifact('typescript'), typeScriptPath, 'junction');
+  }
+
   mockFs({
     '/node_modules/@angular': loadAngularPackages(),
-    '/node_modules/rxjs': loadDirectory(resolveNpmTreeArtifact('rxjs', 'index.js')),
-    '/node_modules/tslib': loadDirectory(resolveNpmTreeArtifact('tslib', 'tslib.js')),
+    '/node_modules/rxjs': loadDirectory(resolveNpmTreeArtifact('rxjs')),
+    '/node_modules/tslib': loadDirectory(resolveNpmTreeArtifact('tslib')),
     '/node_modules/test-package': {
       'package.json': '{"name": "test-package", "es2015": "./index.js", "typings": "./index.d.ts"}',
       // no metadata.json file so not compiled by Angular.