diff --git a/.travis.yml b/.travis.yml
index 37a4996f1a8..b67443c5f67 100755
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,10 +1,12 @@
-os: osx
-
 osx_image: xcode7
 
-env:
-  - NODE_VERSION=6
-  - NODE_VERSION=4
+matrix:
+  include:
+    - os: osx
+      env: NODE_VERSION=6
+
+    - os: osx
+      env: TEST_FILES=osxPackagerTest,CodeSignTest NODE_VERSION=4
 
 language: c
 
diff --git a/docs/Multi Platform Build.md b/docs/Multi Platform Build.md
index 72f976ebf75..0c205beea0e 100755
--- a/docs/Multi Platform Build.md	
+++ b/docs/Multi Platform Build.md	
@@ -3,7 +3,7 @@ Don't expect that you can build app for all platforms on one platform.
 * If your app has native dependencies, it can be compiled only on the target platform.
 [prebuild](https://www.npmjs.com/package/prebuild) is a solution, but most node modules [don't provide](/~https://github.com/atom/node-keytar/issues/27) prebuilt binaries.
 
-* OS Code Signing works only OS X. [Cannot be fixed](http://stackoverflow.com/a/12156576).
+* OS Code Signing works only on OS X. [Cannot be fixed](http://stackoverflow.com/a/12156576).
 * Windows Code Signing doesn't work on Linux. We are going to fix it soon.
 
 Don't think that mentioned issues are major, you should use build servers — e.g. [AppVeyor](http://www.appveyor.com/) to build Windows app and [Travis](https://travis-ci.org) to build OS X/Linux apps.
diff --git a/package.json b/package.json
index 2531c6bbebb..2cc77c2a07a 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,7 @@
     "test": "node ./test/out/helpers/runTests.js",
     "semantic-release": "semantic-release pre && npm publish && semantic-release post",
     "//": "Update wiki if docs changed. Update only if functionalily are generally available (latest release, not next)",
-    "update-wiki": "git subtree split -b wiki --prefix docs/ && git push wiki wiki:master",
+    "update-wiki": "git subtree split -b wiki --prefix docs/ && git push -f wiki wiki:master",
     "whitespace": "whitespace src/*.ts",
     "docker-images": "docker/build.sh"
   },
diff --git a/src/packager.ts b/src/packager.ts
index 467b5dc0cdd..8a065800a4d 100644
--- a/src/packager.ts
+++ b/src/packager.ts
@@ -77,6 +77,10 @@ export class Packager implements BuildInfo {
     // custom packager - don't check wine
     let checkWine = this.options.platformPackagerFactory == null
     for (let [platform, archToType] of this.options.targets!) {
+      if (platform === Platform.OSX && process.platform === Platform.WINDOWS.nodeName) {
+        throw new Error("Build for OS X is supported only on OS X, please see /~https://github.com/electron-userland/electron-builder/wiki/Multi-Platform-Build")
+      }
+
       let wineCheck: Promise<string> | null = null
       if (checkWine && process.platform !== "win32" && platform === Platform.WINDOWS) {
         wineCheck = exec("wine", ["--version"])
diff --git a/test/src/BuildTest.ts b/test/src/BuildTest.ts
index ad149d7c7a4..bccbe874b69 100755
--- a/test/src/BuildTest.ts
+++ b/test/src/BuildTest.ts
@@ -1,5 +1,5 @@
 import test from "./helpers/avaEx"
-import { assertPack, modifyPackageJson, outDirName } from "./helpers/packTester"
+import { assertPack, modifyPackageJson, outDirName, platform } from "./helpers/packTester"
 import { expectedWinContents } from "./helpers/expectedContents"
 import { move, outputFile, outputJson } from "fs-extra-p"
 import { Promise as BluebirdPromise } from "bluebird"
@@ -243,6 +243,8 @@ test("copy extra content", async () => {
   }
 })
 
+test.ifWinCi("Build OS X on Windows is not supported", (t: any) => t.throws(assertPack("test-app-one", platform(Platform.OSX)), /Build for OS X is supported only on OS X.+/))
+
 function allPlatforms(dist: boolean = true): PackagerOptions {
   return {
     targets: getPossiblePlatforms(dist ? null : DIR_TARGET),
diff --git a/test/src/helpers/runTests.ts b/test/src/helpers/runTests.ts
index feb2e23b0e6..3bc8d701edb 100755
--- a/test/src/helpers/runTests.ts
+++ b/test/src/helpers/runTests.ts
@@ -119,7 +119,7 @@ async function copyDependencies() {
 }
 
 /**
- * CIRCLE_NODE_INDEX=3 — test nodejs 4 (on Circle).
+ * CIRCLE_NODE_INDEX=2 — test nodejs 4 (on Circle).
  */
 function runTests(): BluebirdPromise<any> {
   const args: Array<string> = []
@@ -139,7 +139,7 @@ function runTests(): BluebirdPromise<any> {
   }
   else if (!isEmptyOrSpaces(process.env.CIRCLE_NODE_INDEX)) {
     const circleNodeIndex = parseInt(process.env.CIRCLE_NODE_INDEX, 10)
-    if (circleNodeIndex === 0 || circleNodeIndex === 3) {
+    if (circleNodeIndex === 0 || circleNodeIndex === 2) {
       skipWin = true
       args.push(path.join(baseDir, "linuxPackagerTest.js"), path.join(baseDir, "BuildTest.js"))
     }