diff --git a/app/Http/Controllers/Api/ApplicationsController.php b/app/Http/Controllers/Api/ApplicationsController.php
index 9919a8054..074269fa0 100644
--- a/app/Http/Controllers/Api/ApplicationsController.php
+++ b/app/Http/Controllers/Api/ApplicationsController.php
@@ -979,6 +979,9 @@ private function create_application(Request $request, $type)
                     ],
                 ], 422);
             }
+            $request->merge([
+                'custom_nginx_configuration' => $customNginxConfiguration,
+            ]);
         }
 
         $project = Project::whereTeamId($teamId)->whereUuid($request->project_uuid)->first();
@@ -2397,7 +2400,7 @@ public function update_by_uuid(Request $request)
                 }
             }
         }
-        if ($request->has('custom_nginx_configuration')) {
+        if ($request->has('custom_nginx_configuration') && ! is_null($request->custom_nginx_configuration)) {
             if (! isBase64Encoded($request->custom_nginx_configuration)) {
                 return response()->json([
                     'message' => 'Validation failed.',
@@ -2415,6 +2418,9 @@ public function update_by_uuid(Request $request)
                     ],
                 ], 422);
             }
+            $request->merge([
+                'custom_nginx_configuration' => $customNginxConfiguration,
+            ]);
         }
         $return = $this->validateDataApplications($request, $server);
         if ($return instanceof JsonResponse) {
diff --git a/app/Models/Application.php b/app/Models/Application.php
index 2a364e13f..b5a0f0ea9 100644
--- a/app/Models/Application.php
+++ b/app/Models/Application.php
@@ -886,8 +886,8 @@ public function status(): Attribute
     public function customNginxConfiguration(): Attribute
     {
         return Attribute::make(
-            set: fn ($value) => base64_encode($value),
-            get: fn ($value) => base64_decode($value),
+            set: fn ($value) => is_null($value) ? null : base64_encode($value),
+            get: fn ($value) => is_null($value) ? null : base64_decode($value),
         );
     }
 
diff --git a/tests/Feature/ApplicationCustomNginxConfigurationApiTest.php b/tests/Feature/ApplicationCustomNginxConfigurationApiTest.php
new file mode 100644
index 000000000..358003588
--- /dev/null
+++ b/tests/Feature/ApplicationCustomNginxConfigurationApiTest.php
@@ -0,0 +1,150 @@
+<?php
+
+use App\Models\Application;
+use App\Models\Environment;
+use App\Models\InstanceSettings;
+use App\Models\Project;
+use App\Models\Server;
+use App\Models\StandaloneDocker;
+use App\Models\Team;
+use App\Models\User;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Str;
+
+uses(RefreshDatabase::class);
+
+beforeEach(function () {
+    InstanceSettings::unguarded(fn () => InstanceSettings::firstOrCreate(['id' => 0]));
+
+    $this->team = Team::factory()->create();
+    $this->user = User::factory()->create();
+    $this->team->members()->attach($this->user->id, ['role' => 'owner']);
+    session(['currentTeam' => $this->team]);
+
+    $plainTextToken = Str::random(40);
+    $token = $this->user->tokens()->create([
+        'name' => 'custom-nginx-api-test-'.Str::random(6),
+        'token' => hash('sha256', $plainTextToken),
+        'abilities' => ['*'],
+        'team_id' => $this->team->id,
+    ]);
+    $this->bearerToken = $token->getKey().'|'.$plainTextToken;
+
+    $this->server = Server::factory()->create(['team_id' => $this->team->id]);
+    $this->destination = StandaloneDocker::where('server_id', $this->server->id)->first();
+    $this->project = Project::factory()->create(['team_id' => $this->team->id]);
+    $this->environment = Environment::factory()->create(['project_id' => $this->project->id]);
+});
+
+function customNginxApiHeaders(string $bearerToken): array
+{
+    return [
+        'Authorization' => 'Bearer '.$bearerToken,
+        'Content-Type' => 'application/json',
+    ];
+}
+
+function customNginxConfig(): string
+{
+    return <<<'NGINX'
+server {
+    listen 80;
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+}
+NGINX;
+}
+
+function makeCustomNginxApplication(array $overrides = []): Application
+{
+    return Application::factory()->create(array_merge([
+        'environment_id' => test()->environment->id,
+        'destination_id' => test()->destination->id,
+        'destination_type' => test()->destination->getMorphClass(),
+        'build_pack' => 'static',
+    ], $overrides));
+}
+
+describe('PATCH /api/v1/applications/{uuid} custom_nginx_configuration', function () {
+    test('decodes base64 custom nginx configuration before storing it', function () {
+        $application = makeCustomNginxApplication();
+        $configuration = customNginxConfig();
+        $encodedConfiguration = base64_encode($configuration);
+
+        $response = $this->withHeaders(customNginxApiHeaders($this->bearerToken))
+            ->patchJson("/api/v1/applications/{$application->uuid}", [
+                'custom_nginx_configuration' => $encodedConfiguration,
+            ]);
+
+        $response->assertOk();
+
+        $application->refresh();
+        expect($application->custom_nginx_configuration)->toBe($configuration);
+
+        $storedConfiguration = DB::table('applications')
+            ->where('id', $application->id)
+            ->value('custom_nginx_configuration');
+
+        expect($storedConfiguration)->toBe(base64_encode($configuration));
+
+        $this->withHeaders(customNginxApiHeaders($this->bearerToken))
+            ->getJson("/api/v1/applications/{$application->uuid}")
+            ->assertOk()
+            ->assertJsonPath('custom_nginx_configuration', $configuration);
+    });
+
+    test('rejects custom nginx configuration that is not base64 encoded', function () {
+        $application = makeCustomNginxApplication();
+
+        $response = $this->withHeaders(customNginxApiHeaders($this->bearerToken))
+            ->patchJson("/api/v1/applications/{$application->uuid}", [
+                'custom_nginx_configuration' => customNginxConfig(),
+            ]);
+
+        $response->assertUnprocessable()
+            ->assertJsonPath('errors.custom_nginx_configuration', 'The custom_nginx_configuration should be base64 encoded.');
+    });
+
+    test('can clear custom nginx configuration with null', function () {
+        $application = makeCustomNginxApplication([
+            'custom_nginx_configuration' => customNginxConfig(),
+        ]);
+
+        $response = $this->withHeaders(customNginxApiHeaders($this->bearerToken))
+            ->patchJson("/api/v1/applications/{$application->uuid}", [
+                'custom_nginx_configuration' => null,
+            ]);
+
+        $response->assertOk();
+
+        $application->refresh();
+        expect($application->custom_nginx_configuration)->toBeNull();
+    });
+});
+
+describe('POST /api/v1/applications/public custom_nginx_configuration', function () {
+    test('decodes base64 custom nginx configuration before storing it on create', function () {
+        $configuration = customNginxConfig();
+
+        $response = $this->withHeaders(customNginxApiHeaders($this->bearerToken))
+            ->postJson('/api/v1/applications/public', [
+                'project_uuid' => $this->project->uuid,
+                'environment_uuid' => $this->environment->uuid,
+                'server_uuid' => $this->server->uuid,
+                'git_repository' => 'https://gitlab.com/coolify/test-static-app',
+                'git_branch' => 'main',
+                'build_pack' => 'static',
+                'ports_exposes' => '80',
+                'custom_nginx_configuration' => base64_encode($configuration),
+                'autogenerate_domain' => false,
+            ]);
+
+        $response->assertCreated();
+
+        $application = Application::where('uuid', $response->json('uuid'))->firstOrFail();
+
+        expect($application->custom_nginx_configuration)->toBe($configuration);
+    });
+});