Webpack 5.0.0-beta.X compilation.getCache Error

If you’re here, chances are you ran into the following surprise in your Webpack 5-beta build:

TypeError: compilation.getCache is not a function

To fix, you’ll need to update to Webpack 5.0.0-beta.23, which introduces getCache.

From the release notes:

added compilation/compiler.getCache API for easier to use caching

So why did the error appear in the first place?

If you’re experiencing this in your build pipeline, it’s because it’s installing everything from scratch, and terser-webpack-plugin is a caret’d dependency of webpack, which in our case, allows it to grab the latest terser-webpack-plugin which uses the latest webpack cache API.