diff --git a/aio/src/app/nav-engine/doc.service.spec.ts b/aio/src/app/nav-engine/doc.service.spec.ts
index 7de0ad073b..cd5d8df0b5 100644
--- a/aio/src/app/nav-engine/doc.service.spec.ts
+++ b/aio/src/app/nav-engine/doc.service.spec.ts
@@ -9,7 +9,7 @@ import { of } from 'rxjs/observable/of';
 import 'rxjs/add/observable/throw';
 import 'rxjs/add/operator/catch';
 import 'rxjs/add/operator/delay';
-import 'rxjs/add/operator/take';
+import 'rxjs/add/operator/first';
 
 describe('DocService', () => {
   let docFetchingService: DocFetchingService;
@@ -31,7 +31,7 @@ describe('DocService', () => {
     loggerSpy = jasmine.createSpyObj('logger', ['log', 'warn', 'error']);
     docFetchingService = new DocFetchingService(null, loggerSpy);
     getFileSpy = spyOn(docFetchingService, 'getDocFile').and
-      .returnValue(of(testDoc).delay(0).take(1)); // take(1) -> completes
+      .returnValue(of(testDoc).delay(0).first()); // first() -> completes
 
     docService = new DocService(docFetchingService, loggerSpy);
   });
diff --git a/aio/src/app/nav-engine/nav-map.service.spec.ts b/aio/src/app/nav-engine/nav-map.service.spec.ts
index 413bcb6092..5943dbba22 100644
--- a/aio/src/app/nav-engine/nav-map.service.spec.ts
+++ b/aio/src/app/nav-engine/nav-map.service.spec.ts
@@ -19,12 +19,12 @@ describe('NavMapService', () => {
 
   beforeEach(done => {
     httpSpy = jasmine.createSpyObj('http', ['get']);
-    httpSpy.get.and.returnValue(of(getTestNavMapResponse()).delay(0).take(1)); // take(1) -> completes
+    httpSpy.get.and.returnValue(of(getTestNavMapResponse()).delay(0).first()); // first() -> completes
     loggerSpy = jasmine.createSpyObj('logger', ['log', 'warn', 'error']);
 
     navMapService = new NavMapService(new DocFetchingService(null, null), httpSpy, loggerSpy);
 
-    navMapService.navMap.take(1).subscribe(
+    navMapService.navMap.first().subscribe(
       nm => navMap = nm,
       null,
       done);
diff --git a/aio/src/app/sidenav/sidenav.component.spec.ts b/aio/src/app/sidenav/sidenav.component.spec.ts
index ab0d0166c4..f845ce3d11 100644
--- a/aio/src/app/sidenav/sidenav.component.spec.ts
+++ b/aio/src/app/sidenav/sidenav.component.spec.ts
@@ -51,7 +51,7 @@ describe('SidenavComponent', () => {
     };
 
     navEngine = {
-      currentDoc: of(fakeDoc).delay(0).take(1),
+      currentDoc: of(fakeDoc).delay(0).first(),
       navigate: (docId: string) => { }
     } as NavEngine;
     navigateSpy = spyOn(navEngine, 'navigate');
@@ -69,7 +69,7 @@ describe('SidenavComponent', () => {
     };
 
     navMapService = {
-      navMap: of(fakeNavMap).delay(0).take(1)
+      navMap: of(fakeNavMap).delay(0).first()
     } as NavMapService;
 
     TestBed.configureTestingModule({
diff --git a/aio/src/app/sidenav/sidenav.component.ts b/aio/src/app/sidenav/sidenav.component.ts
index b06648a1d0..cc0d39673e 100644
--- a/aio/src/app/sidenav/sidenav.component.ts
+++ b/aio/src/app/sidenav/sidenav.component.ts
@@ -41,7 +41,7 @@ export class SidenavComponent implements OnInit {
         // Side effect: when the current doc changes,
         // get its NavNode and alert the navigation panel
         this.currentDocId = doc.metadata.docId;
-        this.navMapService.navMap.take(1) // take makes sure it completes!
+        this.navMapService.navMap.first() // take makes sure it completes!
         .map(navMap => navMap.docs.get(this.currentDocId))
         .subscribe( node => this.selectedNode.emit(node));
       });