SEO Técnico para Webs Industriales: Lo que vemos, lo que creemos, lo que funciona

/productos/
/productos/{categoria}/
/productos/{categoria}/{producto}/

# Ejemplos reales:
/productos/extrusion/
/productos/extrusion/perfiles-silicona-ferroviario/

<?php
class ProductRepository
{
    public function __construct(
        private PDO $db,
        private CacheInterface $cache
    ) {}

    public function findBySlug(string $slug): ?array
    {
        $key = "product_{$slug}";

        // Si está en caché, devolver directamente
        if ($cached = $this->cache->get($key)) {
            return $cached;
        }

        // Si no, consultar y cachear
        $product = $this->queryProduct($slug);
        
        if ($product) {
            $this->cache->set($key, $product, 3600);
        }

        return $product;
    }

    private function queryProduct(string $slug): ?array
    {
        // Una sola query con JOINs, no 15 queries separadas
        $sql = '
            SELECT p.*, s.nombre as serie_nombre, sec.nombre as sector_nombre
            FROM productos p
            LEFT JOIN series s ON p.serie_id = s.id
            LEFT JOIN sectores sec ON p.sector_id = sec.id
            WHERE p.slug = ?
        ';
        
        $stmt = $this->db->prepare($sql);
        $stmt->execute([$slug]);
        return $stmt->fetch(PDO::FETCH_ASSOC) ?: null;
    }
}

<?php
class ProductSchemaGenerator
{
    public function generate(array $product): array
    {
        $schema = [
            '@context' => 'https://schema.org',
            '@type' => 'Product',
            'name' => $product['nombre'],
            'description' => $product['descripcion_corta'],
            'sku' => $product['sku'],
            'manufacturer' => [
                '@type' => 'Organization',
                'name' => $product['fabricante']
            ],
            'material' => $product['material'],
            'additionalProperty' => []
        ];

        // Propiedades técnicas reales, no genéricas
        if (!empty($product['temp_max'])) {
            $schema['additionalProperty'][] = [
                '@type' => 'PropertyValue',
                'name' => 'Temperatura máxima',
                'value' => $product['temp_max'],
                'unitCode' => 'CEL'
            ];
        }

        if (!empty($product['dureza_shore'])) {
            $schema['additionalProperty'][] = [
                '@type' => 'PropertyValue',
                'name' => 'Dureza Shore A',
                'value' => $product['dureza_shore']
            ];
        }

        if (!empty($product['certificaciones'])) {
            $schema['additionalProperty'][] = [
                '@type' => 'PropertyValue',
                'name' => 'Certificaciones',
                'value' => implode(', ', $product['certificaciones'])
            ];
        }

        return $schema;
    }

    public function render(array $product): void
    {
        $schema = $this->generate($product);
        echo '<script type="application/ld+json">';
        echo json_encode($schema, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE);
        echo '</script>';
    }
}

<?php
class SitemapGenerator
{
    public function __construct(
        private string $baseUrl,
        private ProductRepository $products,
        private SectorRepository $sectors
    ) {}

    public function generateIndex(): string
    {
        $xml = '<?xml version="1.0" encoding="UTF-8"?>';
        $xml .= '<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">';
        
        $sitemaps = ['products', 'sectors', 'processes', 'pages'];
        
        foreach ($sitemaps as $type) {
            $xml .= '<sitemap>';
            $xml .= '<loc>' . $this->baseUrl . '/sitemaps/' . $type . '.xml</loc>';
            $xml .= '<lastmod>' . date('Y-m-d') . '</lastmod>';
            $xml .= '</sitemap>';
        }
        
        $xml .= '</sitemapindex>';
        return $xml;
    }

    public function generateProducts(): string
    {
        $products = $this->products->findAllActive();
        
        $xml = '<?xml version="1.0" encoding="UTF-8"?>';
        $xml .= '<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">';
        
        foreach ($products as $product) {
            $xml .= '<url>';
            $xml .= '<loc>' . $this->baseUrl . '/productos/' . $product['categoria_slug'] . '/' . $product['slug'] . '/</loc>';
            $xml .= '<lastmod>' . $product['updated_at'] . '</lastmod>';
            $xml .= '<changefreq>monthly</changefreq>';
            $xml .= '</url>';
        }
        
        $xml .= '</urlset>';
        return $xml;
    }
}

<?php
class HreflangGenerator
{
    private array $languages = ['es', 'en', 'fr'];
    private string $defaultLang = 'es';

    public function __construct(
        private Router $router,
        private string $baseUrl
    ) {}

    public function render(): void
    {
        $currentPath = $this->router->getPathWithoutLang();
        
        foreach ($this->languages as $lang) {
            $url = $this->buildUrl($lang, $currentPath);
            $hreflang = $lang === $this->defaultLang ? 'x-default' : $lang;
            
            echo '<link rel="alternate" hreflang="' . $lang . '" href="' . $url . '">';
            
            if ($lang === $this->defaultLang) {
                echo '<link rel="alternate" hreflang="x-default" href="' . $url . '">';
            }
        }
    }

    private function buildUrl(string $lang, string $path): string
    {
        if ($lang === $this->defaultLang) {
            return $this->baseUrl . '/' . ltrim($path, '/');
        }
        return $this->baseUrl . '/' . $lang . '/' . ltrim($path, '/');
    }
}