Slow build time due to babel-loader, IgnorePlugin and TerserPlugin

[hubertokf]

I'm using create-react-app in my project but it takes too long to build. It takes about 7 minutes to build on Gitlab CI/CD.

I managed to use react-app-rewired to use the speed-measure-webpack-plugin and see what is taking so long. These are the results that i got running on my own master race desktop:

 SMP  ⏱  
General output time took 2 mins, 18.44 secs

 SMP  ⏱  Plugins
IgnorePlugin took 37.19 secs
TerserPlugin took 20.33 secs
OptimizeCssAssetsWebpackPlugin took 1.42 secs
HtmlWebpackPlugin took 0.121 secs
ManifestPlugin took 0.085 secs
MiniCssExtractPlugin took 0.008 secs
InlineChunkHtmlPlugin took 0.008 secs
DefinePlugin took 0.005 secs
ModuleNotFoundPlugin took 0.004 secs
InterpolateHtmlPlugin took 0.003 secs

 SMP  ⏱  Loaders
babel-loader took 1 min, 45.33 secs
  module count = 9207
modules with no loaders took 8.97 secs
  module count = 150
mini-css-extract-plugin, and 
css-loader, and 
postcss-loader took 8.72 secs
  module count = 11
@svgr/webpack, and 
file-loader took 7.6 secs
  module count = 3
css-loader, and 
postcss-loader took 4.024 secs
  module count = 11
url-loader took 1.19 secs
  module count = 5
file-loader took 0.757 secs
  module count = 14
html-webpack-plugin took 0.027 secs
  module count = 1

As you can see IgnorePlugin and TerserPlugin are taking a huge time.
But what is leading me nuts is that babel-loader is taking 1 min and 45 seconds!

I managed to disable ESLint too using DISABLE_ESLINT_PLUGIN flag

I don't know how to debug this problem as I don't know how to deal with webpack. But I hope someone here could help.

Thanks