diff --git a/flow-typed/npm/mocha_vx.x.x.js b/flow-typed/npm/mocha_vx.x.x.js
index b7c7c13128..f83b48a0b1 100644
--- a/flow-typed/npm/mocha_vx.x.x.js
+++ b/flow-typed/npm/mocha_vx.x.x.js
@@ -31,44 +31,44 @@ declare interface $npm$mocha$Suite {
   fullTitle(): string;
 }
 
-declare interface $npm$mocha$ContextDefinition {
+declare type $npm$mocha$ContextDefinition = {|
   (
     description: string,
     callback: () => /* this: $npm$mocha$SuiteCallbackContext */ void,
-  ): $npm$mocha$Suite;
+  ): $npm$mocha$Suite,
   only(
     description: string,
     callback: () => /* this: $npm$mocha$SuiteCallbackContext */ void,
-  ): $npm$mocha$Suite;
+  ): $npm$mocha$Suite,
   skip(
     description: string,
-    callbac: () => /* this: $npm$mocha$SuiteCallbackContext */ void,
-  ): void;
-  timeout(ms: number): void;
-}
+    callback: () => /* this: $npm$mocha$SuiteCallbackContext */ void,
+  ): void,
+  timeout(ms: number): void,
+|};
 
-declare interface $npm$mocha$TestDefinition {
+declare type $npm$mocha$TestDefinition = {|
   (
     expectation: string,
     callback?: (
       /* this: $npm$mocha$TestCallbackContext, */ done: $npm$mocha$done,
     ) => mixed,
-  ): $npm$mocha$Test;
+  ): $npm$mocha$Test,
   only(
     expectation: string,
     callback?: (
       /* this: $npm$mocha$TestCallbackContext, */ done: $npm$mocha$done,
     ) => mixed,
-  ): $npm$mocha$Test;
+  ): $npm$mocha$Test,
   skip(
     expectation: string,
     callback?: (
       /* this: $npm$mocha$TestCallbackContext, */ done: $npm$mocha$done,
     ) => mixed,
-  ): void;
-  timeout(ms: number): void;
-  state: 'failed' | 'passed';
-}
+  ): void,
+  timeout(ms: number): void,
+  state: 'failed' | 'passed',
+|};
 
 declare interface $npm$mocha$Runner {}
 
@@ -208,98 +208,109 @@ declare var xit: $npm$mocha$TestDefinition;
 declare var test: $npm$mocha$TestDefinition;
 declare var specify: $npm$mocha$TestDefinition;
 
-declare function run(): void;
+type Run = () => void;
 
-declare function setup(
+declare var run: Run;
+
+type Setup = (
   callback: (
     /* this: $npm$mocha$BeforeAndAfterContext, */ done: $npm$mocha$done,
   ) => mixed,
-): void;
-declare function teardown(
+) => void;
+type Teardown = (
   callback: (
     /* this: $npm$mocha$BeforeAndAfterContext, */ done: $npm$mocha$done,
   ) => mixed,
-): void;
-declare function suiteSetup(
+) => void;
+type SuiteSetup = (
   callback: (
     /* this: $npm$mocha$HookCallbackContext, */ done: $npm$mocha$done,
   ) => mixed,
-): void;
-declare function suiteTeardown(
+) => void;
+type SuiteTeardown = (
   callback: (
     /* this: $npm$mocha$HookCallbackContext, */ done: $npm$mocha$done,
   ) => mixed,
-): void;
-declare function before(
+) => void;
+type Before = (
   callback: (
     /* this: $npm$mocha$HookCallbackContext, */ done: $npm$mocha$done,
   ) => mixed,
-): void;
-declare function before(
-  description: string,
+) =>
+  | void
+  | ((
+      description: string,
+      callback: (
+        /* this: $npm$mocha$HookCallbackContext, */ done: $npm$mocha$done,
+      ) => mixed,
+    ) => void);
+type After = (
   callback: (
     /* this: $npm$mocha$HookCallbackContext, */ done: $npm$mocha$done,
   ) => mixed,
-): void;
-declare function after(
-  callback: (
-    /* this: $npm$mocha$HookCallbackContext, */ done: $npm$mocha$done,
-  ) => mixed,
-): void;
-declare function after(
-  description: string,
-  callback: (
-    /* this: $npm$mocha$HookCallbackContext, */ done: $npm$mocha$done,
-  ) => mixed,
-): void;
-declare function beforeEach(
-  callback: (
-    /* this: $npm$mocha$BeforeAndAfterContext, */ done: $npm$mocha$done,
-  ) => mixed,
-): void;
-declare function beforeEach(
-  description: string,
+) =>
+  | void
+  | ((
+      description: string,
+      callback: (
+        /* this: $npm$mocha$HookCallbackContext, */ done: $npm$mocha$done,
+      ) => mixed,
+    ) => void);
+type BeforeEach = (
   callback: (
     /* this: $npm$mocha$BeforeAndAfterContext, */ done: $npm$mocha$done,
   ) => mixed,
-): void;
-declare function afterEach(
+) =>
+  | void
+  | ((
+      description: string,
+      callback: (
+        /* this: $npm$mocha$BeforeAndAfterContext, */ done: $npm$mocha$done,
+      ) => mixed,
+    ) => void);
+type AfterEach = (
   callback: (
     /* this: $npm$mocha$BeforeAndAfterContext, */ done: $npm$mocha$done,
   ) => mixed,
-): void;
-declare function afterEach(
-  description: string,
-  callback: (
-    /* this: $npm$mocha$BeforeAndAfterContext, */ done: $npm$mocha$done,
-  ) => mixed,
-): void;
+) =>
+  | void
+  | ((
+      description: string,
+      callback: (
+        /* this: $npm$mocha$BeforeAndAfterContext, */ done: $npm$mocha$done,
+      ) => mixed,
+    ) => void);
+
+declare var setup: Setup;
+declare var teardown: Teardown;
+declare var suiteSetup: SuiteSetup;
+declare var suiteTeardown;
+declare var before: Before;
+declare var after: After;
+declare var beforeEach: BeforeEach;
+declare var afterEach: AfterEach;
 
 declare module 'mocha' {
-  declare export var mocha: typeof mocha;
-  declare export var describe: typeof describe;
-  declare export var xdescribe: typeof xdescribe;
-  declare export var context: typeof context;
-  declare export var suite: typeof suite;
-  declare export var it: typeof it;
-  declare export var xit: typeof xit;
-  declare export var test: typeof test;
-  declare export var specify: typeof specify;
+  declare export var mocha: $npm$mocha$TestDefinition;
+  declare export var describe: $npm$mocha$ContextDefinition;
+  declare export var xdescribe: $npm$mocha$ContextDefinition;
+  declare export var context: $npm$mocha$ContextDefinition;
+  declare export var suite: $npm$mocha$ContextDefinition;
+  declare export var it: $npm$mocha$TestDefinition;
+  declare export var xit: $npm$mocha$TestDefinition;
+  declare export var test: $npm$mocha$TestDefinition;
+  declare export var specify: $npm$mocha$TestDefinition;
 
-  declare export var run: typeof run;
+  declare export var run: Run;
 
-  declare export var setup: typeof setup;
-  declare export var teardown: typeof teardown;
-  declare export var suiteSetup: typeof suiteSetup;
-  declare export var suiteTeardown: typeof suiteTeardown;
-  declare export var before: typeof before;
-  declare export var before: typeof before;
-  declare export var after: typeof after;
-  declare export var after: typeof after;
-  declare export var beforeEach: typeof beforeEach;
-  declare export var beforeEach: typeof beforeEach;
-  declare export var afterEach: typeof afterEach;
-  declare export var afterEach: typeof afterEach;
+  declare export var setup: Setup;
+  declare export var teardown: Teardown;
+  declare export var suiteSetup: SuiteSetup;
+  declare export var suiteTeardown: SuiteTeardown;
+  declare export var before: Before;
+  declare export var after: After;
+  declare export var beforeEach: BeforeEach;
+  declare export var afterEach: AfterEach;
 
   declare export default $npm$mocha$Mocha;
 }