How can I use memory APIs to persist long-term chatbot context?

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    // Example using Node.js with a simple memory API
    const express = require('express');
    const app = express();
    const memoryStore = {}; // In-memory storage for simplicity

    app.post('/webhook', (req, res) => {
      const userId = req.body.userId;
      const userMessage = req.body.message;

      if (!memoryStore[userId]) {
        memoryStore[userId] = { context: [] };
      }

      memoryStore[userId].context.push(userMessage);

      res.json({ reply: "Context saved!", context: memoryStore[userId].context });
    });

    app.listen(3000, () => console.log('Memory API running on port 3000'));
    <!-- END COPY / PASTE -->