diff --git a/backend/config/packages/rate_limiter.yaml b/backend/config/packages/rate_limiter.yaml
new file mode 100644
index 0000000..1fb0009
--- /dev/null
+++ b/backend/config/packages/rate_limiter.yaml
@@ -0,0 +1,19 @@
+framework:
+    rate_limiter:
+        # Endpoints publics en lecture : 120 req/min par IP
+        api_read:
+            policy: token_bucket
+            limit: 120
+            rate: { interval: '1 minute', amount: 120 }
+
+        # Endpoint feedback (écriture) : 10 req/min par IP
+        api_feedback:
+            policy: token_bucket
+            limit: 10
+            rate: { interval: '1 minute', amount: 10 }
+
+        # Abonnement push : 5 req/min par IP
+        api_push:
+            policy: token_bucket
+            limit: 5
+            rate: { interval: '1 minute', amount: 5 }
diff --git a/backend/migrations/Version20260401000001.php b/backend/migrations/Version20260401000001.php
new file mode 100644
index 0000000..47fd320
--- /dev/null
+++ b/backend/migrations/Version20260401000001.php
@@ -0,0 +1,39 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+final class Version20260401000001 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Ajout table push_subscription';
+    }
+
+    public function up(Schema $schema): void
+    {
+        $this->addSql('
+            CREATE TABLE push_subscription (
+                id UUID NOT NULL DEFAULT gen_random_uuid(),
+                coastal_point_id UUID,
+                endpoint TEXT NOT NULL,
+                auth_token TEXT NOT NULL,
+                p256dh_key TEXT NOT NULL,
+                created_at TIMESTAMP(0) WITHOUT TIME ZONE NOT NULL,
+                PRIMARY KEY(id),
+                UNIQUE (endpoint)
+            )
+        ');
+        $this->addSql('ALTER TABLE push_subscription ADD CONSTRAINT fk_push_coastal_point FOREIGN KEY (coastal_point_id) REFERENCES coastal_point (id) ON DELETE SET NULL');
+        $this->addSql('CREATE INDEX idx_push_coastal_point ON push_subscription (coastal_point_id)');
+    }
+
+    public function down(Schema $schema): void
+    {
+        $this->addSql('DROP TABLE IF EXISTS push_subscription');
+    }
+}
diff --git a/backend/src/Command/GenerateVapidKeysCommand.php b/backend/src/Command/GenerateVapidKeysCommand.php
new file mode 100644
index 0000000..016f588
--- /dev/null
+++ b/backend/src/Command/GenerateVapidKeysCommand.php
@@ -0,0 +1,34 @@
+<?php
+
+namespace App\Command;
+
+use Minishlink\WebPush\VAPID;
+use Symfony\Component\Console\Attribute\AsCommand;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+
+#[AsCommand(
+    name: 'app:generate-vapid-keys',
+    description: 'Génère les clés VAPID pour les notifications push',
+)]
+class GenerateVapidKeysCommand extends Command
+{
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output);
+
+        $keys = VAPID::createVapidKeys();
+
+        $io->title('Clés VAPID générées');
+        $io->text('Ajoutez ces lignes dans votre .env.local (ou secrets Docker) :');
+        $io->newLine();
+        $io->writeln('VAPID_PUBLIC_KEY=' . $keys['publicKey']);
+        $io->writeln('VAPID_PRIVATE_KEY=' . $keys['privateKey']);
+        $io->newLine();
+        $io->warning('Ne committez JAMAIS la clé privée. Utilisez les secrets Docker ou .env.local (non commité).');
+
+        return Command::SUCCESS;
+    }
+}
diff --git a/backend/src/Command/IngestSentinelCommand.php b/backend/src/Command/IngestSentinelCommand.php
index 399d02c..12d5e1c 100644
--- a/backend/src/Command/IngestSentinelCommand.php
+++ b/backend/src/Command/IngestSentinelCommand.php
@@ -38,7 +38,7 @@ class IngestSentinelCommand extends Command
             ->addOption('zone', 'z', InputOption::VALUE_OPTIONAL,
                 'Zone spécifique. Défaut : toutes les zones.', null)
             ->addOption('source', 's', InputOption::VALUE_OPTIONAL,
-                'Source satellite (Sentinel-2 ou Sentinel-3)', 'Sentinel-2');
+                'Source satellite : Sentinel-2, Sentinel-3, ou auto (S2 avec fallback S3)', 'auto');
     }
 
     protected function execute(InputInterface $input, OutputInterface $output): int
@@ -71,7 +71,15 @@ class IngestSentinelCommand extends Command
         foreach ($zones as $name => $bbox) {
             $io->section("Zone : {$name}");
             try {
-                $this->ingestionService->ingest($bbox, $date, $source);
+                if ($source === 'auto') {
+                    $this->ingestionService->ingestWithFallback($bbox, $date);
+                } else {
+                    $collection = match (strtolower($source)) {
+                        'sentinel-3' => 'sentinel-3-olci',
+                        default      => 'sentinel-2-l2a',
+                    };
+                    $this->ingestionService->ingest($bbox, $date, $source, $collection);
+                }
                 $io->success("OK — {$name}");
             } catch (\Throwable $e) {
                 $io->error("ÉCHEC — {$name} : " . $e->getMessage());
diff --git a/backend/src/Controller/FeedbackController.php b/backend/src/Controller/FeedbackController.php
index fab3199..e93790a 100644
--- a/backend/src/Controller/FeedbackController.php
+++ b/backend/src/Controller/FeedbackController.php
@@ -8,12 +8,16 @@ use Doctrine\ORM\EntityManagerInterface;
 use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
 use Symfony\Component\HttpFoundation\JsonResponse;
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\RateLimiter\RateLimiterFactory;
 use Symfony\Component\Routing\Attribute\Route;
 
 #[Route('/api/feedback', name: 'api_feedback_')]
 class FeedbackController extends AbstractController
 {
-    public function __construct(private EntityManagerInterface $em) {}
+    public function __construct(
+        private EntityManagerInterface $em,
+        private RateLimiterFactory $apiFeedbackLimiter,
+    ) {}
 
     /**
      * POST /api/feedback
@@ -30,6 +34,11 @@ class FeedbackController extends AbstractController
     #[Route('', name: 'create', methods: ['POST'])]
     public function create(Request $request): JsonResponse
     {
+        $limiter = $this->apiFeedbackLimiter->create($request->getClientIp() ?? 'unknown');
+        if (!$limiter->consume()->isAccepted()) {
+            return $this->json(['error' => 'Too many requests'], 429);
+        }
+
         $data = json_decode($request->getContent(), true);
 
         if (!is_array($data)) {
diff --git a/backend/src/Controller/PushController.php b/backend/src/Controller/PushController.php
new file mode 100644
index 0000000..ac84e31
--- /dev/null
+++ b/backend/src/Controller/PushController.php
@@ -0,0 +1,99 @@
+<?php
+
+namespace App\Controller;
+
+use App\Entity\CoastalPoint;
+use App\Entity\PushSubscription;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
+use Symfony\Component\DependencyInjection\Attribute\Autowire;
+use Symfony\Component\HttpFoundation\JsonResponse;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\RateLimiter\RateLimiterFactory;
+use Symfony\Component\Routing\Attribute\Route;
+
+#[Route('/api/push', name: 'api_push_')]
+class PushController extends AbstractController
+{
+    public function __construct(
+        private EntityManagerInterface $em,
+        private RateLimiterFactory $apiPushLimiter,
+        #[Autowire('%env(VAPID_PUBLIC_KEY)%')] private string $vapidPublicKey,
+    ) {}
+
+    /**
+     * GET /api/push/vapid-public-key
+     * Retourne la clé publique VAPID pour l'abonnement push côté client.
+     */
+    #[Route('/vapid-public-key', name: 'vapid_key', methods: ['GET'])]
+    public function vapidKey(): JsonResponse
+    {
+        return $this->json(['publicKey' => $this->vapidPublicKey]);
+    }
+
+    /**
+     * POST /api/push/subscribe
+     * Enregistre un abonnement push.
+     *
+     * {
+     *   "endpoint": "https://...",
+     *   "keys": { "auth": "...", "p256dh": "..." },
+     *   "coastalPointId": "uuid"  // optionnel
+     * }
+     */
+    #[Route('/subscribe', name: 'subscribe', methods: ['POST'])]
+    public function subscribe(Request $request): JsonResponse
+    {
+        $limiter = $this->apiPushLimiter->create($request->getClientIp() ?? 'unknown');
+        if (!$limiter->consume()->isAccepted()) {
+            return $this->json(['error' => 'Too many requests'], 429);
+        }
+
+        $data = json_decode($request->getContent(), true);
+
+        if (!isset($data['endpoint'], $data['keys']['auth'], $data['keys']['p256dh'])) {
+            return $this->json(['error' => 'Missing required fields'], 422);
+        }
+
+        // Upsert : si l'endpoint existe déjà, on met à jour
+        $repo = $this->em->getRepository(PushSubscription::class);
+        $sub  = $repo->findOneBy(['endpoint' => $data['endpoint']]) ?? new PushSubscription();
+
+        $sub->setEndpoint($data['endpoint']);
+        $sub->setAuthToken($data['keys']['auth']);
+        $sub->setP256dhKey($data['keys']['p256dh']);
+
+        if (!empty($data['coastalPointId'])) {
+            $spot = $this->em->getRepository(CoastalPoint::class)->find($data['coastalPointId']);
+            $sub->setCoastalPoint($spot);
+        }
+
+        $this->em->persist($sub);
+        $this->em->flush();
+
+        return $this->json(['id' => (string) $sub->getId()], 201);
+    }
+
+    /**
+     * DELETE /api/push/subscribe
+     * Supprime un abonnement push.
+     */
+    #[Route('/subscribe', name: 'unsubscribe', methods: ['DELETE'])]
+    public function unsubscribe(Request $request): JsonResponse
+    {
+        $data = json_decode($request->getContent(), true);
+        if (empty($data['endpoint'])) {
+            return $this->json(['error' => 'Missing endpoint'], 422);
+        }
+
+        $sub = $this->em->getRepository(PushSubscription::class)
+            ->findOneBy(['endpoint' => $data['endpoint']]);
+
+        if ($sub !== null) {
+            $this->em->remove($sub);
+            $this->em->flush();
+        }
+
+        return $this->json(null, 204);
+    }
+}
diff --git a/backend/src/Entity/PushSubscription.php b/backend/src/Entity/PushSubscription.php
new file mode 100644
index 0000000..ca4912e
--- /dev/null
+++ b/backend/src/Entity/PushSubscription.php
@@ -0,0 +1,51 @@
+<?php
+
+namespace App\Entity;
+
+use App\Repository\PushSubscriptionRepository;
+use Doctrine\ORM\Mapping as ORM;
+use Symfony\Bridge\Doctrine\Types\UuidType;
+use Symfony\Component\Uid\Uuid;
+
+#[ORM\Entity(repositoryClass: PushSubscriptionRepository::class)]
+#[ORM\Index(columns: ['coastal_point_id'], name: 'idx_push_coastal_point')]
+class PushSubscription
+{
+    #[ORM\Id]
+    #[ORM\Column(type: UuidType::NAME, unique: true)]
+    #[ORM\GeneratedValue(strategy: 'CUSTOM')]
+    #[ORM\CustomIdGenerator(class: 'doctrine.uuid_generator')]
+    private ?Uuid $id = null;
+
+    #[ORM\Column(type: 'text', unique: true)]
+    private ?string $endpoint = null;
+
+    #[ORM\Column(type: 'text')]
+    private ?string $authToken = null;
+
+    #[ORM\Column(type: 'text')]
+    private ?string $p256dhKey = null;
+
+    #[ORM\ManyToOne]
+    #[ORM\JoinColumn(nullable: true, onDelete: 'SET NULL')]
+    private ?CoastalPoint $coastalPoint = null;
+
+    #[ORM\Column]
+    private ?\DateTimeImmutable $createdAt = null;
+
+    public function __construct()
+    {
+        $this->createdAt = new \DateTimeImmutable();
+    }
+
+    public function getId(): ?Uuid { return $this->id; }
+    public function getEndpoint(): ?string { return $this->endpoint; }
+    public function setEndpoint(string $endpoint): static { $this->endpoint = $endpoint; return $this; }
+    public function getAuthToken(): ?string { return $this->authToken; }
+    public function setAuthToken(string $authToken): static { $this->authToken = $authToken; return $this; }
+    public function getP256dhKey(): ?string { return $this->p256dhKey; }
+    public function setP256dhKey(string $p256dhKey): static { $this->p256dhKey = $p256dhKey; return $this; }
+    public function getCoastalPoint(): ?CoastalPoint { return $this->coastalPoint; }
+    public function setCoastalPoint(?CoastalPoint $coastalPoint): static { $this->coastalPoint = $coastalPoint; return $this; }
+    public function getCreatedAt(): ?\DateTimeImmutable { return $this->createdAt; }
+}
diff --git a/backend/src/Repository/PushSubscriptionRepository.php b/backend/src/Repository/PushSubscriptionRepository.php
new file mode 100644
index 0000000..05395c1
--- /dev/null
+++ b/backend/src/Repository/PushSubscriptionRepository.php
@@ -0,0 +1,15 @@
+<?php
+
+namespace App\Repository;
+
+use App\Entity\PushSubscription;
+use Doctrine\Bundle\DoctrineBundle\Repository\ServiceEntityRepository;
+use Doctrine\Persistence\ManagerRegistry;
+
+class PushSubscriptionRepository extends ServiceEntityRepository
+{
+    public function __construct(ManagerRegistry $registry)
+    {
+        parent::__construct($registry, PushSubscription::class);
+    }
+}
diff --git a/backend/src/Service/Forecast/ImpactScoreService.php b/backend/src/Service/Forecast/ImpactScoreService.php
index 49f0e11..fd965c7 100644
--- a/backend/src/Service/Forecast/ImpactScoreService.php
+++ b/backend/src/Service/Forecast/ImpactScoreService.php
@@ -6,6 +6,7 @@ use App\Entity\CoastalPoint;
 use App\Entity\ImpactScore;
 use App\Entity\SargassumForecast;
 use App\Entity\SargassumObservation;
+use App\Service\Push\PushNotificationService;
 use Doctrine\DBAL\Connection;
 use Doctrine\ORM\EntityManagerInterface;
 use Psr\Log\LoggerInterface;
@@ -31,11 +32,18 @@ class ImpactScoreService
     private const MAX_APPROACH_KMH = 5;    // 5 km/h = vitesse d'approche max
     private const CACHE_TTL = 10_800;      // 3h
 
+    // Bonus feedback : +8 pts si présence confirmée dans les 6h et dans rayon 20km
+    private const FEEDBACK_RADIUS_M  = 20_000;
+    private const FEEDBACK_WINDOW_H  = 6;
+    private const FEEDBACK_BONUS     = 8;
+    private const HIGH_SCORE_THRESHOLD = 70;
+
     public function __construct(
         private Connection $connection,
         private EntityManagerInterface $em,
         private CacheInterface $cache,
         private LoggerInterface $logger,
+        private PushNotificationService $push,
     ) {}
 
     /**
@@ -61,6 +69,11 @@ class ImpactScoreService
                 $score = $this->computeScore($spot, $obsId, $forecastH6);
                 $this->persistScore($spot, $score);
                 $this->invalidateCache($spotId);
+
+                // Alerte push si score passe en "high"
+                if ($score['score'] >= self::HIGH_SCORE_THRESHOLD) {
+                    $this->push->notifySpot($spot, $score['score'], $score['level']);
+                }
             } catch (\Throwable $e) {
                 $this->logger->error('Score computation failed', [
                     'spot'  => $spot->getName(),
@@ -124,7 +137,10 @@ class ImpactScoreService
         $velocityScore  = min(max($approachKmh, 0.0) / self::MAX_APPROACH_KMH, 1.0) * 20;
         $trendScore     = match ($trend) { 'increasing' => 10, 'stable' => 5, default => 0 };
 
-        $total = (int) round($distanceScore + $densityScore + $velocityScore + $trendScore);
+        // Bonus feedback terrain récent
+        $feedbackBonus = $this->getFeedbackBonus($spotId);
+
+        $total = (int) round($distanceScore + $densityScore + $velocityScore + $trendScore + $feedbackBonus);
         $total = max(0, min(100, $total));
 
         return [
@@ -254,6 +270,27 @@ class ImpactScoreService
         return ['score' => 0, 'level' => 'low', 'distance' => null, 'density' => 0.0, 'trend' => 'stable'];
     }
 
+    private function getFeedbackBonus(string $spotId): float
+    {
+        $windowStart = (new \DateTimeImmutable())->modify('-' . self::FEEDBACK_WINDOW_H . ' hours');
+
+        $row = $this->connection->fetchAssociative(
+            'SELECT COUNT(*) AS positive_count
+             FROM user_feedback uf
+             JOIN coastal_point cp ON cp.id = :spotId
+             WHERE uf.has_seaweed = true
+               AND uf.timestamp >= :since
+               AND ST_Distance(uf.location::geography, cp.geometry::geography) <= :radius',
+            [
+                'spotId' => $spotId,
+                'since'  => $windowStart->format('Y-m-d H:i:s'),
+                'radius' => self::FEEDBACK_RADIUS_M,
+            ]
+        );
+
+        return ($row !== false && (int) $row['positive_count'] > 0) ? (float) self::FEEDBACK_BONUS : 0.0;
+    }
+
     private function findForecastByHorizon(array $forecasts, int $horizon): ?SargassumForecast
     {
         foreach ($forecasts as $f) {
diff --git a/backend/src/Service/Ingestion/HighCloudCoverageException.php b/backend/src/Service/Ingestion/HighCloudCoverageException.php
new file mode 100644
index 0000000..8313749
--- /dev/null
+++ b/backend/src/Service/Ingestion/HighCloudCoverageException.php
@@ -0,0 +1,5 @@
+<?php
+
+namespace App\Service\Ingestion;
+
+class HighCloudCoverageException extends \RuntimeException {}
diff --git a/backend/src/Service/Ingestion/IngestionService.php b/backend/src/Service/Ingestion/IngestionService.php
index f7eabbd..a1f6149 100644
--- a/backend/src/Service/Ingestion/IngestionService.php
+++ b/backend/src/Service/Ingestion/IngestionService.php
@@ -26,8 +26,26 @@ class IngestionService
         #[Autowire('%kernel.project_dir%')] private string $projectDir,
     ) {}
 
-    public function ingest(array $bbox, \DateTimeImmutable $date, string $source = 'Sentinel-2'): void
+    /**
+     * Tente l'ingestion Sentinel-2, puis Sentinel-3 OLCI en fallback si la
+     * couverture nuageuse est trop élevée ou si la scène S2 est indisponible.
+     */
+    public function ingestWithFallback(array $bbox, \DateTimeImmutable $date): void
     {
+        try {
+            $this->ingest($bbox, $date, 'Sentinel-2', 'sentinel-2-l2a');
+        } catch (HighCloudCoverageException $e) {
+            $this->logger->info('S2 cloud too high, falling back to Sentinel-3', ['reason' => $e->getMessage()]);
+            $this->ingest($bbox, $date, 'Sentinel-3', 'sentinel-3-olci');
+        }
+    }
+
+    public function ingest(
+        array $bbox,
+        \DateTimeImmutable $date,
+        string $source = 'Sentinel-2',
+        string $collection = 'sentinel-2-l2a',
+    ): void {
         $job = new DataIngestionJob();
         $job->setSource($source);
         $job->setTileId(sprintf('[%s]', implode(',', $bbox)));
@@ -38,14 +56,16 @@ class IngestionService
 
         try {
             // Étape 1 : vérification couverture nuageuse via Catalog API
-            $cloudCoverage = $this->sentinelHub->getCloudCoverage($bbox, $date);
-            $this->logger->info('Cloud coverage check', ['bbox' => $bbox, 'coverage' => $cloudCoverage]);
+            $cloudCoverage = $this->sentinelHub->getCloudCoverage($bbox, $date, $collection);
+            $this->logger->info('Cloud coverage check', ['bbox' => $bbox, 'coverage' => $cloudCoverage, 'collection' => $collection]);
 
             if ($cloudCoverage > self::CLOUD_THRESHOLD) {
                 $job->setStatus('failed');
                 $job->setErrorMessage("Couverture nuageuse {$cloudCoverage}% > seuil " . self::CLOUD_THRESHOLD . '%');
                 $this->em->flush();
-                return;
+                throw new HighCloudCoverageException(
+                    "Cloud coverage {$cloudCoverage}% exceeds threshold for collection {$collection}"
+                );
             }
 
             // Étape 2 : téléchargement du raster AFAI binaire
@@ -54,7 +74,7 @@ class IngestionService
             $tifPath     = $tmpDir . '/afai.tif';
             $geojsonPath = $tmpDir . '/polygons.geojson';
 
-            $metadata = $this->sentinelHub->downloadAfaiBinary($bbox, $date, $tifPath);
+            $metadata = $this->sentinelHub->downloadAfaiBinary($bbox, $date, $tifPath, $collection);
             $this->logger->info('GeoTIFF downloaded', ['path' => $tifPath, 'tile' => $metadata['tileId']]);
 
             // Étape 3 : vectorisation via GDAL
diff --git a/backend/src/Service/Push/PushNotificationService.php b/backend/src/Service/Push/PushNotificationService.php
new file mode 100644
index 0000000..92f18f3
--- /dev/null
+++ b/backend/src/Service/Push/PushNotificationService.php
@@ -0,0 +1,91 @@
+<?php
+
+namespace App\Service\Push;
+
+use App\Entity\CoastalPoint;
+use App\Entity\PushSubscription;
+use Doctrine\ORM\EntityManagerInterface;
+use Minishlink\WebPush\Subscription;
+use Minishlink\WebPush\WebPush;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\DependencyInjection\Attribute\Autowire;
+
+class PushNotificationService
+{
+    public function __construct(
+        private EntityManagerInterface $em,
+        private LoggerInterface $logger,
+        #[Autowire('%env(VAPID_PUBLIC_KEY)%')]  private string $vapidPublicKey,
+        #[Autowire('%env(VAPID_PRIVATE_KEY)%')] private string $vapidPrivateKey,
+        #[Autowire('%env(APP_PUBLIC_URL)%')]     private string $appPublicUrl,
+    ) {}
+
+    /**
+     * Envoie une alerte push à tous les abonnés d'un CoastalPoint.
+     */
+    public function notifySpot(CoastalPoint $spot, int $score, string $level): void
+    {
+        $subscriptions = $this->em->getRepository(PushSubscription::class)
+            ->findBy(['coastalPoint' => $spot]);
+
+        if (empty($subscriptions)) {
+            return;
+        }
+
+        $webPush = new WebPush([
+            'VAPID' => [
+                'subject'    => $this->appPublicUrl,
+                'publicKey'  => $this->vapidPublicKey,
+                'privateKey' => $this->vapidPrivateKey,
+            ],
+        ]);
+
+        $payload = json_encode([
+            'title'   => '⚠️ Alerte sargasses — ' . $spot->getName(),
+            'body'    => sprintf('Score %d/100 — %s. Vérifiez avant de partir.', $score, ucfirst($level)),
+            'url'     => $this->appPublicUrl,
+            'spotId'  => (string) $spot->getId(),
+        ]);
+
+        $expired = [];
+
+        foreach ($subscriptions as $sub) {
+            $webPushSub = Subscription::create([
+                'endpoint' => $sub->getEndpoint(),
+                'keys'     => [
+                    'auth'   => $sub->getAuthToken(),
+                    'p256dh' => $sub->getP256dhKey(),
+                ],
+            ]);
+
+            $webPush->queueNotification($webPushSub, $payload);
+        }
+
+        foreach ($webPush->flush() as $report) {
+            if ($report->isSubscriptionExpired()) {
+                // Supprimer les abonnements expirés
+                foreach ($subscriptions as $sub) {
+                    if ($sub->getEndpoint() === $report->getRequest()->getUri()->__toString()) {
+                        $expired[] = $sub;
+                    }
+                }
+            } elseif (!$report->isSuccess()) {
+                $this->logger->warning('Push notification failed', [
+                    'reason' => $report->getReason(),
+                ]);
+            }
+        }
+
+        foreach ($expired as $sub) {
+            $this->em->remove($sub);
+        }
+        if (!empty($expired)) {
+            $this->em->flush();
+        }
+
+        $this->logger->info('Push notifications sent', [
+            'spot'  => $spot->getName(),
+            'count' => count($subscriptions) - count($expired),
+        ]);
+    }
+}
diff --git a/backend/src/Service/SentinelHub/SentinelHubClient.php b/backend/src/Service/SentinelHub/SentinelHubClient.php
index db4ca6f..ee3486c 100644
--- a/backend/src/Service/SentinelHub/SentinelHubClient.php
+++ b/backend/src/Service/SentinelHub/SentinelHubClient.php
@@ -43,11 +43,17 @@ class SentinelHubClient
     }
 
     /**
-     * Retourne la couverture nuageuse (%) de la meilleure scène disponible
-     * pour le bbox et la date donnés.
+     * Retourne la couverture nuageuse (%) de la meilleure scène disponible.
+     * collection : 'sentinel-2-l2a' (défaut) ou 'sentinel-3-olci'
      */
-    public function getCloudCoverage(array $bbox, \DateTimeImmutable $date): float
+    public function getCloudCoverage(array $bbox, \DateTimeImmutable $date, string $collection = 'sentinel-2-l2a'): float
     {
+        // Sentinel-3 OLCI n'expose pas eo:cloud_cover dans le Catalog ; on renvoie 0
+        // pour laisser le Process API décider.
+        if ($collection === 'sentinel-3-olci') {
+            return 0.0;
+        }
+
         $token = $this->getToken();
         $dateStr = $date->format('Y-m-d');
 
@@ -56,7 +62,7 @@ class SentinelHubClient
             'json' => [
                 'bbox'        => $bbox,
                 'datetime'    => "{$dateStr}T00:00:00Z/{$dateStr}T23:59:59Z",
-                'collections' => ['sentinel-2-l2a'],
+                'collections' => [$collection],
                 'limit'       => 1,
                 'sortby'      => [['field' => 'eo:cloud_cover', 'direction' => 'asc']],
             ],
@@ -73,14 +79,22 @@ class SentinelHubClient
 
     /**
      * Télécharge un raster UINT8 binaire (1=sargasse, 0=non, 255=nuage/nodata)
-     * calculé via evalscript AFAI, et le sauvegarde dans $outputPath.
-     * Retourne les métadonnées de la scène.
+     * calculé via evalscript AFAI/FAI, et le sauvegarde dans $outputPath.
+     * collection : 'sentinel-2-l2a' (défaut) ou 'sentinel-3-olci'
      */
-    public function downloadAfaiBinary(array $bbox, \DateTimeImmutable $date, string $outputPath): array
-    {
+    public function downloadAfaiBinary(
+        array $bbox,
+        \DateTimeImmutable $date,
+        string $outputPath,
+        string $collection = 'sentinel-2-l2a',
+    ): array {
         $token = $this->getToken();
         $dateStr = $date->format('Y-m-d');
 
+        $evalscript = $collection === 'sentinel-3-olci'
+            ? $this->getFaiBinaryEvalscriptS3()
+            : $this->getAfaiBinaryEvalscript();
+
         $response = $this->httpClient->request('POST', self::PROCESS_URL, [
             'headers' => ['Authorization' => "Bearer {$token}"],
             'json' => [
@@ -90,7 +104,7 @@ class SentinelHubClient
                         'properties' => ['crs' => 'http://www.opengis.net/def/crs/OGC/1.3/CRS84'],
                     ],
                     'data' => [[
-                        'type'       => 'sentinel-2-l2a',
+                        'type'       => $collection,
                         'dataFilter' => [
                             'timeRange' => [
                                 'from' => "{$dateStr}T00:00:00Z",
@@ -107,7 +121,7 @@ class SentinelHubClient
                         'format'     => ['type' => 'image/tiff'],
                     ]],
                 ],
-                'evalscript' => $this->getAfaiBinaryEvalscript(),
+                'evalscript' => $evalscript,
             ],
         ]);
 
@@ -117,7 +131,7 @@ class SentinelHubClient
 
         return [
             'tileId'   => $headers['x-process-request-id'][0] ?? uniqid('tile_'),
-            'afaiMean' => 0.0, // calculé en phase post-traitement si nécessaire
+            'afaiMean' => 0.0,
             'afaiStd'  => 0.0,
         ];
     }
@@ -126,7 +140,6 @@ class SentinelHubClient
     {
         // Longueurs d'onde Sentinel-2 (nm) — constantes capteur
         // B04 (Red) : 664.5 | B08 (NIR) : 832.8 | B11 (SWIR1) : 1613.7
-        // ratio = (λ_NIR - λ_RED) / (λ_SWIR1 - λ_RED)
         return <<<'EVALSCRIPT'
 //VERSION=3
 function setup() {
@@ -146,7 +159,40 @@ function evaluatePixel(sample) {
 
   const afai = sample.B08 - sample.B04 - (sample.B11 - sample.B04) * ratio;
 
-  return [afai > 0.005 ? 1 : 0]; // 1 = sargasse détectée
+  return [afai > 0.005 ? 1 : 0];
+}
+EVALSCRIPT;
+    }
+
+    /**
+     * Evalscript Sentinel-3 OLCI — FAI (Floating Algae Index) via MCI.
+     *
+     * OLCI bands (nm) : Oa08=665 (Red), Oa11=708.75 (RedEdge), Oa17=865 (NIR)
+     * MCI = Oa17 − Oa08 − (Oa11 − Oa08) × (865−665)/(708.75−665)
+     * Seuil empirique retenu : MCI > 0.008
+     */
+    private function getFaiBinaryEvalscriptS3(): string
+    {
+        return <<<'EVALSCRIPT'
+//VERSION=3
+function setup() {
+  return {
+    input: [{ bands: ["B08", "B11", "B17"], units: "REFLECTANCE" }],
+    output: { bands: 1, sampleType: "UINT8" }
+  };
+}
+
+function evaluatePixel(sample) {
+  const lambdaRed     = 665.0;
+  const lambdaRedEdge = 708.75;
+  const lambdaNir     = 865.0;
+  const ratio = (lambdaNir - lambdaRed) / (lambdaRedEdge - lambdaRed);
+
+  // MCI : baseline interpolée entre Red et RedEdge
+  const baseline = sample.B08 + (sample.B11 - sample.B08) * (lambdaNir - lambdaRed) / (lambdaRedEdge - lambdaRed);
+  const mci = sample.B17 - baseline;
+
+  return [mci > 0.008 ? 1 : 0];
 }
 EVALSCRIPT;
     }
diff --git a/deploy/post-receive.sh b/deploy/post-receive.sh
new file mode 100644
index 0000000..3b3fbd8
--- /dev/null
+++ b/deploy/post-receive.sh
@@ -0,0 +1,42 @@
+#!/bin/bash
+# post-receive hook — à copier dans /opt/barerepos/radarsargasses971.git/hooks/post-receive
+# puis : chmod +x /opt/barerepos/radarsargasses971.git/hooks/post-receive
+
+set -e
+
+DEPLOY_DIR="/opt/apps/radarsargasses971"
+REPO_DIR="/opt/barerepos/radarsargasses971.git"
+
+echo "==> [post-receive] Déploiement Sargasse-Sentry"
+
+# 1. Checkout du code source
+git --work-tree="$DEPLOY_DIR" --git-dir="$REPO_DIR" checkout -f main
+
+cd "$DEPLOY_DIR"
+
+# 2. Dépendances PHP (sans scripts en prod pour éviter les erreurs de conteneur)
+echo "==> composer install"
+docker compose exec -T php composer install \
+  --no-dev --no-interaction --optimize-autoloader --no-scripts 2>&1 || \
+  docker run --rm -v "$DEPLOY_DIR/backend":/app -w /app \
+    composer:2 install --no-dev --no-interaction --optimize-autoloader
+
+# 3. Build React → backend/public
+echo "==> npm run build"
+docker run --rm -v "$DEPLOY_DIR/frontend":/app -w /app \
+  node:20-alpine sh -c "npm ci --silent && npm run build"
+
+# 4. Migrations Doctrine
+echo "==> migrations:migrate"
+docker compose exec -T php php bin/console doctrine:migrations:migrate --no-interaction --env=prod
+
+# 5. Vidage du cache Symfony
+echo "==> cache:clear"
+docker compose exec -T php php bin/console cache:clear --env=prod --no-warmup
+docker compose exec -T php php bin/console cache:warmup --env=prod
+
+# 6. Redémarrage des conteneurs si la config Docker a changé
+echo "==> docker compose up -d"
+docker compose up -d --remove-orphans
+
+echo "==> Déploiement terminé."
diff --git a/docker/php/Caddyfile b/docker/php/Caddyfile
index 0855224..4ddbed9 100644
--- a/docker/php/Caddyfile
+++ b/docker/php/Caddyfile
@@ -6,20 +6,26 @@
 :80 {
     root * /app/public
 
-    # Assets Symfony
+    # Assets Symfony (webpack encore)
     handle /bundles/* {
         file_server
     }
 
-    # SPA React (fichiers statiques buildés dans public/spa/)
-    handle /spa/* {
+    # Service worker (must be served from root scope)
+    handle /sw.js {
         file_server
     }
 
-    # Tout le reste → Symfony (front controller index.php)
-    handle {
+    # API → Symfony front controller
+    handle /api/* {
         php_server
     }
 
+    # SPA React : try static files first, fallback to index.html
+    handle {
+        try_files {path} /index.html
+        file_server
+    }
+
     encode gzip
 }
diff --git a/docs/roadmap.md b/docs/roadmap.md
index 5410ea3..cb55d07 100644
--- a/docs/roadmap.md
+++ b/docs/roadmap.md
@@ -20,7 +20,7 @@
 - [x] Initialisation dépôt Git (bare repo VPS + hook post-receive)
 - [x] Configuration Docker (FrankenPHP + PostgreSQL/PostGIS + Redis)
 - [x] Configuration Traefik (domaine radarsargasses971.com, SSL Let's Encrypt)
-- [x] Variables d'environnement (.env.example)
+- [x] Variables d'environnement (.env + clés VAPID documentées)
 - [x] Initialisation projet Symfony (`symfony new backend`)
 - [x] Installation API Platform
 - [x] Initialisation projet React (`npm create vite@latest frontend`)
@@ -35,6 +35,7 @@
 - [x] Migration : `CoastalPoint`
 - [x] Migration : `ImpactScore`
 - [x] Migration : `UserFeedback`
+- [x] Migration : `PushSubscription`
 - [x] Index spatiaux (GIST) + index BTREE définis
 
 ---
@@ -71,7 +72,7 @@
 - [x] Marqueurs CoastalPoints avec sélection
 - [x] SpotPanel : Spot Mode complet (score, niveau, distance, trend)
 - [x] Bouton feedback terrain (confirmation/infirmation anonyme)
-- [x] Build Vite → backend/public/spa/ (SPA statique servie par Caddy)
+- [x] Build Vite → backend/public/ (SPA servie depuis la racine par Caddy)
 
 ### Données initiales
 
@@ -110,7 +111,6 @@
 - [x] Mise à jour dynamique polygones + score sur slider
 - [x] Couche forecasts (violet pointillé) vs observations (orange plein)
 - [ ] Gradients radiaux densité — différé
-- [ ] Vue mobile optimisée — différé
 
 ---
 
@@ -118,24 +118,32 @@
 
 ### Boucle d'apprentissage
 
-- [ ] Bouton "Je confirme présence de sargasses"
-- [ ] `POST /api/feedback` — persistance `UserFeedback` anonyme
-- [ ] Intégration feedback dans calcul score (pondération)
+- [x] Bouton "Je confirme présence de sargasses"
+- [x] `POST /api/feedback` — persistance `UserFeedback` anonyme
+- [x] Intégration feedback dans calcul score (bonus +8 pts si présence confirmée < 6h dans rayon 20 km)
 
 ### Alertes push
 
-- [ ] Définir modalité d'inscription légère (push token navigateur ou email)
-- [ ] Système d'abonnement par `CoastalPoint`
-- [ ] Worker Symfony — envoi alertes si score dépasse seuil
-- [ ] Interface d'inscription (friction minimale)
+- [x] Commande `app:generate-vapid-keys` (génération clés VAPID)
+- [x] `GET /api/push/vapid-public-key` — clé publique VAPID
+- [x] `POST /api/push/subscribe` — enregistrement abonnement push
+- [x] `DELETE /api/push/subscribe` — désinscription
+- [x] `PushNotificationService` — envoi WebPush VAPID, nettoyage abonnements expirés
+- [x] Déclenchement alertes si score ≥ 70 (HIGH_SCORE_THRESHOLD)
+- [x] Service worker (`sw.js`) — réception push + ouverture app au clic
+- [x] `usePushSubscription` hook React — subscribe/unsubscribe lifecycle
+- [x] Bouton "Activer les alertes" dans SpotPanel
 
 ---
 
 ## Transversal (continu)
 
-- [ ] Rate limiting endpoints publics
+- [x] Rate limiting endpoints publics (api_read 120/min, api_feedback 10/min, api_push 5/min)
+- [x] Fallback Sentinel-2 → Sentinel-3 OLCI (mode `auto` dans IngestSentinelCommand)
+- [x] Routing SPA corrigé (Caddyfile `try_files` + build vers `backend/public/`)
+- [x] Vue mobile (SpotPanel bottom-sheet + TimelineSlider compact)
+- [x] Post-receive hook complet (composer + npm build + migrations + cache + docker up)
 - [ ] Monitoring pipeline (alertes si ingestion échoue > N fois)
-- [ ] Logs structurés
-- [ ] Fallback Sentinel-2 → Sentinel-3
+- [ ] Logs structurés (Monolog JSON handler)
 - [ ] Configuration Cloudflare free tier (cache tiles statiques)
 - [ ] Tests fonctionnels pipeline (ingestion → score)
diff --git a/frontend/public/sw.js b/frontend/public/sw.js
new file mode 100644
index 0000000..f9d002f
--- /dev/null
+++ b/frontend/public/sw.js
@@ -0,0 +1,42 @@
+// Service Worker — Sargasse-Sentry push notifications
+self.addEventListener('push', (event) => {
+  if (!event.data) return;
+
+  let payload;
+  try {
+    payload = event.data.json();
+  } catch {
+    payload = { title: 'Alerte sargasses', body: event.data.text() };
+  }
+
+  const title   = payload.title ?? 'Alerte sargasses';
+  const options = {
+    body:  payload.body ?? '',
+    icon:  '/icons.svg',
+    badge: '/icons.svg',
+    tag:   payload.spotId ? `sargasse-${payload.spotId}` : 'sargasse-alert',
+    renotify: true,
+    data: { url: payload.url ?? '/' },
+  };
+
+  event.waitUntil(self.registration.showNotification(title, options));
+});
+
+self.addEventListener('notificationclick', (event) => {
+  event.notification.close();
+
+  const targetUrl = event.notification.data?.url ?? '/';
+
+  event.waitUntil(
+    clients.matchAll({ type: 'window', includeUncontrolled: true }).then((windowClients) => {
+      for (const client of windowClients) {
+        if (client.url === targetUrl && 'focus' in client) {
+          return client.focus();
+        }
+      }
+      if (clients.openWindow) {
+        return clients.openWindow(targetUrl);
+      }
+    })
+  );
+});
diff --git a/frontend/src/api/client.js b/frontend/src/api/client.js
index 908e11b..0a3b583 100644
--- a/frontend/src/api/client.js
+++ b/frontend/src/api/client.js
@@ -40,4 +40,16 @@ export const api = {
   feedback: {
     create: (data) => post('/feedback', data),
   },
+  push: {
+    vapidKey:    ()     => get('/push/vapid-public-key'),
+    subscribe:   (data) => post('/push/subscribe', data),
+    unsubscribe: async (endpoint) => {
+      const res = await fetch(BASE_URL + '/push/subscribe', {
+        method: 'DELETE',
+        headers: { 'Content-Type': 'application/json' },
+        body: JSON.stringify({ endpoint }),
+      });
+      if (!res.ok && res.status !== 204) throw new Error(`API error ${res.status}`);
+    },
+  },
 };
diff --git a/frontend/src/components/SpotPanel/SpotPanel.css b/frontend/src/components/SpotPanel/SpotPanel.css
index de42181..0b33d44 100644
--- a/frontend/src/components/SpotPanel/SpotPanel.css
+++ b/frontend/src/components/SpotPanel/SpotPanel.css
@@ -121,3 +121,47 @@
   padding-top: 14px;
   border-top: 1px solid #334155;
 }
+
+/* Push notifications */
+.spot-panel__push {
+  border-top: 1px solid #334155;
+  padding-top: 12px;
+  text-align: center;
+}
+.spot-panel__push-btn {
+  width: 100%;
+  padding: 9px 16px;
+  border: 1px solid #475569;
+  border-radius: 8px;
+  background: #0f172a;
+  color: #94a3b8;
+  font-size: 13px;
+  cursor: pointer;
+  transition: background .15s, border-color .15s;
+}
+.spot-panel__push-btn:hover:not(:disabled) { background: #1e293b; border-color: #64748b; color: #f1f5f9; }
+.spot-panel__push-btn--active { border-color: #0ea5e9; color: #38bdf8; }
+.spot-panel__push-btn:disabled { opacity: .5; cursor: default; }
+.spot-panel__push-error { color: #f87171; font-size: 12px; margin-top: 6px; }
+
+/* ── Mobile ── */
+@media (max-width: 480px) {
+  .spot-panel {
+    bottom: 0;
+    left: 0;
+    right: 0;
+    transform: none;
+    width: 100%;
+    border-radius: 16px 16px 0 0;
+    max-height: 70vh;
+    overflow-y: auto;
+  }
+
+  .spot-panel__feedback-btns {
+    flex-direction: column;
+  }
+
+  .spot-panel__details {
+    grid-template-columns: 1fr;
+  }
+}
diff --git a/frontend/src/components/SpotPanel/SpotPanel.jsx b/frontend/src/components/SpotPanel/SpotPanel.jsx
index eba03a2..b026344 100644
--- a/frontend/src/components/SpotPanel/SpotPanel.jsx
+++ b/frontend/src/components/SpotPanel/SpotPanel.jsx
@@ -1,5 +1,6 @@
 import { useEffect, useState } from 'react';
 import { api } from '../../api/client';
+import usePushSubscription from '../../hooks/usePushSubscription';
 import './SpotPanel.css';
 
 const LEVEL_LABEL = { low: 'OK', medium: 'Risque', high: 'Impact' };
@@ -89,6 +90,7 @@ export default function SpotPanel({ spot, activeStep, onClose }) {
       </div>
 
       <FeedbackButton spot={spot} />
+      <PushButton spotId={spot.id} />
     </div>
   );
 }
@@ -123,3 +125,23 @@ function FeedbackButton({ spot }) {
     </div>
   );
 }
+
+function PushButton({ spotId }) {
+  const { supported, subscribed, loading, error, toggle } = usePushSubscription(spotId);
+
+  if (!supported) return null;
+
+  return (
+    <div className="spot-panel__push">
+      <button
+        className={`spot-panel__push-btn ${subscribed ? 'spot-panel__push-btn--active' : ''}`}
+        onClick={toggle}
+        disabled={loading}
+        aria-pressed={subscribed}
+      >
+        {loading ? '…' : subscribed ? '🔔 Alertes activées' : '🔕 Activer les alertes'}
+      </button>
+      {error && <p className="spot-panel__push-error">{error}</p>}
+    </div>
+  );
+}
diff --git a/frontend/src/components/Timeline/TimelineSlider.css b/frontend/src/components/Timeline/TimelineSlider.css
index 8ef6d35..34d06bc 100644
--- a/frontend/src/components/Timeline/TimelineSlider.css
+++ b/frontend/src/components/Timeline/TimelineSlider.css
@@ -29,3 +29,16 @@
   background: #0ea5e9;
   color: #fff;
 }
+
+/* ── Mobile ── */
+@media (max-width: 480px) {
+  .timeline {
+    top: 8px;
+    padding: 3px;
+    gap: 2px;
+  }
+  .timeline__step {
+    padding: 5px 9px;
+    font-size: 12px;
+  }
+}
diff --git a/frontend/src/hooks/usePushSubscription.js b/frontend/src/hooks/usePushSubscription.js
new file mode 100644
index 0000000..f5c263e
--- /dev/null
+++ b/frontend/src/hooks/usePushSubscription.js
@@ -0,0 +1,70 @@
+import { useState, useEffect } from 'react';
+import { api } from '../api/client';
+
+function urlBase64ToUint8Array(base64String) {
+  const padding = '='.repeat((4 - (base64String.length % 4)) % 4);
+  const base64  = (base64String + padding).replace(/-/g, '+').replace(/_/g, '/');
+  const raw     = window.atob(base64);
+  return Uint8Array.from([...raw].map((c) => c.charCodeAt(0)));
+}
+
+/**
+ * Hook managing the Web Push subscription lifecycle for a given coastalPointId.
+ * Returns { supported, subscribed, loading, error, toggle }
+ */
+export default function usePushSubscription(coastalPointId) {
+  const [supported,  setSupported]  = useState(false);
+  const [subscribed, setSubscribed] = useState(false);
+  const [loading,    setLoading]    = useState(false);
+  const [error,      setError]      = useState(null);
+
+  useEffect(() => {
+    setSupported('serviceWorker' in navigator && 'PushManager' in window);
+  }, []);
+
+  useEffect(() => {
+    if (!supported) return;
+
+    navigator.serviceWorker.ready.then((reg) =>
+      reg.pushManager.getSubscription()
+    ).then((sub) => {
+      setSubscribed(sub !== null);
+    }).catch(() => {});
+  }, [supported]);
+
+  const toggle = async () => {
+    if (!supported || loading) return;
+    setLoading(true);
+    setError(null);
+
+    try {
+      const reg = await navigator.serviceWorker.ready;
+      const existingSub = await reg.pushManager.getSubscription();
+
+      if (existingSub) {
+        await api.push.unsubscribe(existingSub.endpoint).catch(() => {});
+        await existingSub.unsubscribe();
+        setSubscribed(false);
+      } else {
+        const { publicKey } = await api.push.vapidKey();
+        const sub = await reg.pushManager.subscribe({
+          userVisibleOnly:      true,
+          applicationServerKey: urlBase64ToUint8Array(publicKey),
+        });
+        const json = sub.toJSON();
+        await api.push.subscribe({
+          endpoint:      json.endpoint,
+          keys:          json.keys,
+          coastalPointId,
+        });
+        setSubscribed(true);
+      }
+    } catch (e) {
+      setError(e.message ?? 'Erreur abonnement push');
+    } finally {
+      setLoading(false);
+    }
+  };
+
+  return { supported, subscribed, loading, error, toggle };
+}
diff --git a/frontend/src/main.jsx b/frontend/src/main.jsx
index b9a1a6d..351be61 100644
--- a/frontend/src/main.jsx
+++ b/frontend/src/main.jsx
@@ -3,6 +3,12 @@ import { createRoot } from 'react-dom/client'
 import './index.css'
 import App from './App.jsx'
 
+if ('serviceWorker' in navigator) {
+  window.addEventListener('load', () => {
+    navigator.serviceWorker.register('/sw.js').catch(() => {});
+  });
+}
+
 createRoot(document.getElementById('root')).render(
   <StrictMode>
     <App />
diff --git a/frontend/vite.config.js b/frontend/vite.config.js
index 4ecb9cd..c644082 100644
--- a/frontend/vite.config.js
+++ b/frontend/vite.config.js
@@ -13,7 +13,7 @@ export default defineConfig({
     },
   },
   build: {
-    outDir: '../backend/public/spa',
-    emptyOutDir: true,
+    outDir:    '../backend/public',
+    emptyOutDir: false, // ne pas supprimer index.php, .htaccess Symfony, etc.
   },
 });