const katex = require('katex'); const express = require('express'); const bodyParser = require('body-parser'); app = express(); app.use(bodyParser.json()); app.post('/render', (req, res) => { res.send(req.body.equations.map(eq => katex.renderToString(eq.str, { throwOnError: false, displayMode: eq.display }))); }); app.listen(8000);