diff --git a/jest/index.d.ts b/jest/index.d.ts
index dc0260cebb..cf50596d55 100644
--- a/jest/index.d.ts
+++ b/jest/index.d.ts
@@ -91,7 +91,7 @@ declare namespace jest {
     }
 
     interface ProvidesCallback {
-        (cb?: DoneCallback): any;
+        (cb: DoneCallback): any;
     }
 
     interface Lifecycle {
@@ -99,7 +99,7 @@ declare namespace jest {
     }
 
     interface It {
-        (name: string, fn: ProvidesCallback): void;
+        (name: string, fn?: ProvidesCallback): void;
         only: It;
         skip: It;
         concurrent: It;
diff --git a/jest/jest-tests.ts b/jest/jest-tests.ts
index 4b81f6282c..913a671fa1 100644
--- a/jest/jest-tests.ts
+++ b/jest/jest-tests.ts
@@ -358,3 +358,12 @@ describe('genMockFromModule', function () {
       });
     });
 });
+
+/**
+ * Pass strictNullChecks
+ */
+describe('strictNullChecks', function () {
+    it('does not complain when using done callback', (done) => {
+        done();
+    })
+});
diff --git a/jest/tsconfig.json b/jest/tsconfig.json
index 0ad43c6b19..da1e33c024 100644
--- a/jest/tsconfig.json
+++ b/jest/tsconfig.json
@@ -3,7 +3,7 @@
         "module": "commonjs",
         "target": "es6",
         "noImplicitAny": true,
-        "strictNullChecks": false,
+        "strictNullChecks": true,
         "baseUrl": "../",
         "typeRoots": [
             "../"