My webpack.config.js file is as follows:
var path = require(\'path\');
var webpack = require(\'webpack\');
var CommonsChunkPlugin = webpack.optimize.CommonsC         
        Your config uses this configuration as default:
config.devtool = 'eval-source-map';
The fine manual states:
eval-source-map- Each module is executed withevaland a SourceMap is added as DataUrl to theeval.
If you don't want that, use another devtool option.
As for decreasing code size, you probably want to either disable the creation of a source map entirely (just don't set the devtool option) or have Webpack write the source map to a separate file (devtool : 'source-map' or devtool : 'cheap-source-map', AFAIK).
Also set the NODE_ENV environment variable to production if you want less code:
# if you're on a Unix-like OS:
env NODE_ENV=production webpack -p