diff --git a/src/application/sim-controller.ts b/src/application/sim-controller.ts
new file mode 100644
index 0000000..c942f9c
--- /dev/null
+++ b/src/application/sim-controller.ts
@@ -0,0 +1,21 @@
+import { type Request, type Response, type NextFunction } from 'express';
+import { SimUsecases } from './sim-usecases.js';
+import ejs from 'ejs';
+import path from 'path';
+
+export class SimController {
+    constructor(private usecases: SimUsecases) {}
+
+    renderDashboard = async (req: Request, res: Response, next: NextFunction) => {
+        try {
+            const proyectos = await this.usecases.getDashboardData();
+            const filePath = path.join(process.cwd(), 'src/views/index.ejs');
+            ejs.renderFile(filePath, { proyectos }, (err, str) => {
+                if (err) return next(err);
+                res.send(str);
+            });
+        } catch (err) {
+            next(err);
+        }
+    }
+}
diff --git a/src/application/sim-usecases.ts b/src/application/sim-usecases.ts
new file mode 100644
index 0000000..936cd0f
--- /dev/null
+++ b/src/application/sim-usecases.ts
@@ -0,0 +1,57 @@
+import axios from 'axios';
+import { type Pool } from 'pg';
+import { type Proyecto, RepositoryError } from '../domain/common.js';
+
+export class SimUsecases {
+    constructor(private db: Pool) {}
+
+    async checkAllProjectsHealth(): Promise<void> {
+        try {
+            const { rows: projects } = await this.db.query<Proyecto>('SELECT * FROM proyectos');
+
+            const checks = projects.map(async (p) => {
+                let status: Proyecto['estado_codigo'] = 'OK';
+                try {
+                    // Solo 200 es válido: cualquier otro código (301, 403, 5xx) indica un problema real del servicio.
+                    await axios.get(p.url_health, { timeout: 5000, validateStatus: (s) => s === 200 });
+                } catch (e) {
+                    const axiosError = e as { code?: string };
+                    status = axiosError.code === 'ECONNABORTED' ? 'TIMEOUT' : 'ERROR';
+                }
+
+                return this.db.query(
+                    'INSERT INTO estados (proyecto_id, estado_codigo, fecha) VALUES ($1, $2, NOW())',
+                    [p.id, status]
+                );
+            });
+
+            // allSettled en lugar de all: un fallo al insertar en BD no debe cancelar el resto de checks.
+            await Promise.allSettled(checks);
+        } catch (err) {
+            throw new RepositoryError('Fallo masivo en el chequeo de salud', { cause: err instanceof Error ? err.message : String(err) });
+        }
+    }
+
+    async getDashboardData(): Promise<Proyecto[]> {
+        // LEFT JOIN LATERAL nos deja calcular "la última fila de estados" para cada proyecto.
+        // Usamos LEFT JOIN para no perder proyectos que todavía no tienen estados registrados.
+        const query = `
+            SELECT p.id, p.nombre, p.url_health, e.estado_codigo, e.fecha
+            FROM proyectos p
+            LEFT JOIN LATERAL (
+                SELECT estado_codigo, fecha
+                FROM estados
+                WHERE proyecto_id = p.id
+                ORDER BY fecha DESC
+                LIMIT 1
+            ) e ON true
+            ORDER BY p.nombre ASC;
+        `;
+        try {
+            const { rows } = await this.db.query<Proyecto>(query);
+            return rows;
+        } catch (err) {
+            throw new RepositoryError('Error al recuperar datos del dashboard', { cause: err instanceof Error ? err.message : String(err) });
+        }
+    }
+}
diff --git a/src/config/postgreConfig.ts b/src/config/postgreConfig.ts
index 43eb035..b71db16 100644
--- a/src/config/postgreConfig.ts
+++ b/src/config/postgreConfig.ts
@@ -4,9 +4,9 @@ import dotenv from 'dotenv';
 dotenv.config();
 
 export const pool = new pg.Pool({
-    host: process.env.DB_HOST || 'localhost',
-    port: Number(process.env.DB_PORT) || 5432,
-    user: process.env.DB_USER || 'postgres',
-    password: process.env.DB_PASSWORD || 'password',
-    database: process.env.DB_NAME || 'monitor_db'
-});
\ No newline at end of file
+    host: process.env.DB_HOST,
+    port: Number(process.env.DB_PORT),
+    user: process.env.DB_USER,
+    password: process.env.DB_PASSWORD,
+    database: process.env.DB_NAME
+});
diff --git a/src/domain/common.ts b/src/domain/common.ts
index 0262007..4d5330e 100644
--- a/src/domain/common.ts
+++ b/src/domain/common.ts
@@ -4,8 +4,6 @@ export class AppError extends Error {
         this.name = 'AppError';
     }
 }
-
-export class ValidationError extends AppError { constructor(msg: string, details = {}) { super(msg, 400, details); this.name = 'ValidationError'; } }
 export class RepositoryError extends AppError { constructor(msg: string, details = {}) { super(msg, 500, details); this.name = 'RepositoryError'; } }
 
 export interface Proyecto {
diff --git a/src/infrastructure/sim-routes-http.ts b/src/infrastructure/sim-routes-http.ts
new file mode 100644
index 0000000..1764b80
--- /dev/null
+++ b/src/infrastructure/sim-routes-http.ts
@@ -0,0 +1,10 @@
+import { Router } from 'express';
+import { SimController } from '../application/sim-controller.js';
+import { SimUsecases } from '../application/sim-usecases.js';
+
+export function createRouter(usecases: SimUsecases): Router {
+    const router = Router();
+    const controller = new SimController(usecases);
+    router.get('/', controller.renderDashboard);
+    return router;
+}
\ No newline at end of file