The “cost of loading modules” diagram shows non-linear behaviour (though you should largely ignore the curve visible in the diagram because the x axis is way of

The “cost of loading modules” diagram shows non-linear behaviour (though you should largely ignore the curve visible in the diagram because the x axis is way off linear): • 0.15s ÷ 500 = 0.3ms • 0.31s ÷ 1000 = 0.31ms • 3.12s ÷ 10000 = 0.312ms • 16.81s ÷ 25000 = 0.6724ms • 48.44s ÷ 50000 = 0.9688ms My own observation on a Surface Book six years ago was that in Node.js under Windows, each module had about 1ms of overhead when there was warm file system cache—that is, simply bundling with Rollup saved 1ms per file. If this sort of thing interests you, quite a lot of useful stuff came out of https://github.com/stylelint/stylelint/issues/2454 https://github.com/stylelint/stylelint/issues/2454 which I filed because I was unhappy with stylelint taking over a second to import. And that must have been only in the order of one or two thousand modules, when the behaviour is still close enough to linear.