diff --git a/Md03_Dev_Back_end/Bloco21/21.4/README.md b/Md03_Dev_Back_end/Bloco21/21.4/README.md
new file mode 100644
index 00000000..e69de29b
diff --git a/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/.eslintignore b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/.eslintignore
new file mode 100644
index 00000000..8d9740ad
--- /dev/null
+++ b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/.eslintignore
@@ -0,0 +1,3 @@
+// .eslintignore
+
+node_modules
\ No newline at end of file
diff --git a/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/.eslintrc.json b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/.eslintrc.json
new file mode 100644
index 00000000..9cf09375
--- /dev/null
+++ b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/.eslintrc.json
@@ -0,0 +1,10 @@
+// .eslintrc.json
+{
+  "env": {
+    "es2020": true
+  },
+  "extends": "trybe-backend",
+  "rules": {
+    "sonarjs/no-duplicate-string": ["error", 5]
+  }
+}
\ No newline at end of file
diff --git a/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/app.js b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/app.js
new file mode 100644
index 00000000..2bdaadca
--- /dev/null
+++ b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/app.js
@@ -0,0 +1,16 @@
+// src/app.js
+const express = require('express');
+const route = require('./routes/rotas');
+
+const app = express();
+
+app.use(express.json());
+app.use(route);
+
+
+
+// GET / HTTP/1.1
+// Host: developer.mozilla.org
+// Accept: text/html
+
+module.exports = app;
\ No newline at end of file
diff --git a/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/database/teams.js b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/database/teams.js
new file mode 100644
index 00000000..7c65bf23
--- /dev/null
+++ b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/database/teams.js
@@ -0,0 +1,9 @@
+const teams = [
+
+  { id: 1, nome: 'São Paulo Futebol Clube', sigla: 'SPF' },
+
+  { id: 2, nome: 'Sociedade Esportiva Palmeiras', sigla: 'PAL' },
+
+];
+
+module.exports = teams;
\ No newline at end of file
diff --git a/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/index.js b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/index.js
new file mode 100644
index 00000000..e69de29b
diff --git a/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/middlewares/validateTeam.js b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/middlewares/validateTeam.js
new file mode 100644
index 00000000..a612f3d3
--- /dev/null
+++ b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/middlewares/validateTeam.js
@@ -0,0 +1,34 @@
+const teams = require("../database/teams");
+const NOT_FOUND = 404;
+
+const validateTeam = (req, res, next) => {
+  const requiredProperties = ['nome', 'sigla'];
+
+  if (requiredProperties.every((property) => property in req.body)) {
+    next(); // Chama o próximo middleware
+  } else {
+    res.sendStatus(400); // Ou já responde avisando que deu errado
+  }
+};
+
+const validateId = (req, res, next) => {
+  const id = Number(req.params.id);
+
+  if (Number.isNaN(id)) res.status(400).send({ message: 'id não numerico' });
+
+  return next();
+}
+
+const existingId = (req, res, next) => {
+  const idParam = Number(req.params.id);
+
+  if (teams.some(({ id }) => id === idParam)) next();
+
+  return res.status(NOT_FOUND).send({ message: 'id não encontrado' });
+}
+
+module.exports = {
+  validateTeam,
+  validateId,
+  existingId
+};
\ No newline at end of file
diff --git a/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/routes/rotas.js b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/routes/rotas.js
new file mode 100644
index 00000000..aac72130
--- /dev/null
+++ b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/routes/rotas.js
@@ -0,0 +1,54 @@
+const express = require('express');
+const teams = require('../database/teams');
+const { validateId, existingId, validateTeam } = require('../middlewares/validateTeam');
+
+const OK = 200;
+// const INTERNAL_SERVER_ERROR = 500;
+
+const route = express.Router();
+
+let nextId = 3;
+
+route.get('/', (_req, res) => res.status(OK).json({ message: 'Olá Mundo!' }));
+
+route.get('/teams', (req, res) => res.status(OK).json({ teams }));
+
+route.get('/teams/:id', validateId, existingId, (req, res) => {
+  const { id } = req.params;
+  const teamEsp = teams.find((team) => team.id === Number(id));
+
+    res.status(OK).json({ teamEsp });
+});
+
+// Arranja os middlewares para chamar validateTeam primeiro
+route.post('/teams', validateTeam, (req, res) => {
+  const team = { id: nextId, ...req.body };
+
+  teams.push(team);
+  nextId += 1;
+  res.status(201).json(team);
+});
+
+route.put('/teams/:id', validateTeam, validateId, existingId, (req, res) => {
+  const id = Number(req.params.id);
+  const team = teams.find(t => t.id === id);
+
+    const index = teams.indexOf(team);
+    const updated = { id, ...req.body };
+
+    teams.splice(index, 1, updated);
+    res.status(201).json(updated);
+});
+
+
+route.delete('/teams/:id', validateId, existingId, (req, res) => {
+  const id = Number(req.params.id);
+  const team = teams.find(t => t.id === id);
+  const index = teams.indexOf(team);
+
+  teams.splice(index, 1);
+  res.sendStatus(204);
+});
+
+
+module.exports = route;
\ No newline at end of file
diff --git a/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/server.js b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/server.js
new file mode 100644
index 00000000..389396a0
--- /dev/null
+++ b/Md03_Dev_Back_end/Bloco21/21.4/soccer-team-manager/src/server.js
@@ -0,0 +1,4 @@
+// src/server.js
+const app = require('./app');
+
+app.listen(3002, () => console.log('server running on port 3002'));
\ No newline at end of file