build.js

const pkg = require("./package.json");
const fs = require("fs");
const p = require("path");

var deleteFolderRecursive = function(path) {
  if (fs.existsSync(path)) {
    fs.readdirSync(path).forEach(function(file, index){
      var curPath = p.join(path,file);
      if (fs.lstatSync(curPath).isDirectory()) { // recurse
        deleteFolderRecursive(curPath);
      } else { // delete file
        fs.unlinkSync(curPath);
      }
    });
    fs.rmdirSync(path);
  }
};

deleteFolderRecursive(`./docs/${pkg.name}/${pkg.version}`);