How to set mode to development or production in the config file?

webpack webpack-4
hk1ll3r picture hk1ll3r · Mar 12, 2018 · Viewed 13.6k times · Source

We are migrating to webpack 4. We do have dev / prod config files already. We started getting this warning message:

WARNING in configuration
The 'mode' option has not been set. Set 'mode' option to 'development' 
or 'production' to enable defaults for this environment.

We can get around this by passing --mode production in the cmdline like below:

npm run webpack --mode development ...

As is mentioned on the webpack documentation, blog and everywhere else on the internet. How can we set the config in the config file? Simply putting a mode: development under modules won't work. Just a bit frustrated why the documentation is just missing...

Answer

Burrich picture Burrich · Mar 12, 2018

I was looking to the same answer right now, for me it seems that adding the property to the config file do the job.

module.exports = {
  // ...
  mode: 'development'
};

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