You close the loop

The final checkpoint 🚀

Your team has come a long way: it started as a card in the console, grew into a team with statistics, and in React you gave it a face on screen. But all of that lived in the code: if you reload, it's gone. Real apps remember.

Today you close the loop: your team moves to a database (SQL) and is served by an API (Node). This is full-stack.

The journey of a piece of data

When your screen asks for the team, the data makes this journey:

[ Database ]  →  [ API / server ]  →  [ Interface ]
   SQL (the table)   Node (the handler)    React (③)

• The database stores the team permanently. You query it with SQL.
• The API (an Express handler) reads that data and returns it as JSON.
• The interface (your React component from the previous checkpoint) renders it.

You'll build it from the ground up

• SQL: query your team and its average age in the team table.
• Node: write the handlers that serve the list and the statistic as JSON.

Each handler receives (req, res). In the tests we call it with a simulated request and response (crearReq/crearRes), like a toy Express. 👇

Examples

A handler in action — press Run

function listTeam(req, res) {
  res.json([
    { name: "Ana", age: 26 },
    { name: "Beto", age: 36 },
  ]);
}

// In the tests it's called with simulated req/res:
const res = crearRes();
listTeam(crearReq(), res);
console.log("Status:", res.statusCode);
console.log("Body:", res.body);