electron/docs/development/build-instructions-windows.md

# Build instructions (Windows)

## Prerequisites

* Windows 7 / Server 2008 R2 or higher
* Visual Studio 2013 - [download VS 2013 Community Edition for
  free](http://www.visualstudio.com/products/visual-studio-community-vs)
* [Python 2.7](http://www.python.org/download/releases/2.7/)
* 32bit [node.js](http://nodejs.org/download/)
* [git](http://git-scm.com)

If you don't have a Windows installation at the moment,
[modern.ie](https://www.modern.ie/en-us/virtualization-tools#downloads) has
timebombed versions of Windows that you can use to build Atom Shell.

The building of atom-shell is done entirely with command-line scripts, so you
can use any editor you like to develop atom-shell, but it also means you can
not use Visual Studio for the development. Support of building with Visual
Studio will come in the future.

**Note:** Even though Visual Studio is not used for building, it's still
**required** because we need the build toolchains it provided.

## Getting the code

```powershell
git clone https://github.com/atom/atom-shell.git
```

## Bootstrapping

The bootstrap script will download all necessary build dependencies and create
build project files. Notice that we're using `ninja` to build atom-shell so
there is no Visual Studio project generated.

```powershell
cd atom-shell
python script\bootstrap.py
```

## Building

Build both Release and Debug targets:

```powershell
python script\build.py
```

You can also only build the Debug target:

```powershell
python script\build.py -c Debug
```

After building is done, you can find `atom.exe` under `out\Debug`.

## 64bit support

Currently atom-shell can only be built for 32bit target on Windows, support for
64bit will come in future.

## Tests

```powershell
python script\test.py
```

## Troubleshooting

### Command xxxx not found

If you encountered an error like `Command xxxx not found`, you may try to use
the `VS2012 Command Prompt` console to execute the build scripts.

### Assertion failed: ((handle))->activecnt >= 0

If building under Cygwin, you may see `bootstrap.py` failed with following
error:

```
Assertion failed: ((handle))->activecnt >= 0, file src\win\pipe.c, line 1430

Traceback (most recent call last):
  File "script/bootstrap.py", line 87, in <module>
    sys.exit(main())
  File "script/bootstrap.py", line 22, in main
    update_node_modules('.')
  File "script/bootstrap.py", line 56, in update_node_modules
    execute([NPM, 'install'])
  File "/home/zcbenz/codes/raven/script/lib/util.py", line 118, in execute
    raise e
subprocess.CalledProcessError: Command '['npm.cmd', 'install']' returned non-zero exit status 3
```

This is caused by a bug when using Cygwin python and Win32 node together. The
solution is to use the Win32 python to execute the bootstrap script (supposing
you have installed python under `C:\Python27`):

```bash
/cygdrive/c/Python27/python.exe script/bootstrap.py
```

### LNK1181: cannot open input file 'kernel32.lib'

Try reinstalling 32bit node.js.

### Error: ENOENT, stat 'C:\Users\USERNAME\AppData\Roaming\npm'

Simply making that directory [should fix the problem](http://stackoverflow.com/a/25095327/102704):

```powershell
mkdir ~\AppData\Roaming\npm
```