Processing all runs out of heapspace using remark

heapfailure.js

'use strict';

const fs = require('fs');
const processIncludes = require('./preprocess');
const unified = require('unified');
const markdown = require('remark-parse');
const remark2rehype = require('remark-rehype');
const html = require('rehype-stringify');

const inputFile = '../../doc/api/all.md';
let input = fs.readFileSync(inputFile, 'utf8');
console.log(input);

processIncludes(inputFile, input, (err, fulltext) => {
  unified()
    .use(markdown)
    .use(remark2rehype)
    .use(html)
    .process(fulltext, (err, text) => {console.log(err || text)});
})