diff --git a/app/Services/DefaultCachedScraperService.php b/app/Services/DefaultCachedScraperService.php
index adb32c2..3ea7986 100644
--- a/app/Services/DefaultCachedScraperService.php
+++ b/app/Services/DefaultCachedScraperService.php
@@ -7,10 +7,11 @@ use App\Contracts\Repository;
 use App\Http\HttpHelper;
 use App\Support\CachedData;
 use Illuminate\Contracts\Database\Query\Builder;
+use Illuminate\Support\Carbon;
 use Illuminate\Support\Collection;
 use Jikan\MyAnimeList\MalClient;
+use JMS\Serializer\SerializerInterface;
 use MongoDB\BSON\UTCDateTime;
-use JMS\Serializer\Serializer;
 use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;
 
 /**
@@ -21,7 +22,7 @@ final class DefaultCachedScraperService implements CachedScraperService
     public function __construct(
         private readonly Repository $repository,
         private readonly MalClient $jikan,
-        private readonly Serializer $serializer,
+        private readonly SerializerInterface $serializer,
     )
     {
     }
@@ -143,9 +144,7 @@ final class DefaultCachedScraperService implements CachedScraperService
         // insert cache if resource doesn't exist
         if ($results->isEmpty()) {
             $this->repository->insert($response->toArray());
-        }
-
-        if ($results->isExpired()) {
+        } else if ($results->isExpired()) {
             $this->getQueryableByCacheKey($cacheKey)->update($response->toArray());
         }
 
@@ -157,13 +156,15 @@ final class DefaultCachedScraperService implements CachedScraperService
         $meta = [];
         if ($resultsEmpty) {
             $meta = [
-                'createdAt' => new UTCDateTime(),
+                // Using Carbon here for testability
+                'createdAt' => new UTCDateTime(Carbon::now()->getPreciseTimestamp(3)),
                 'request_hash' => $cacheKey
             ];
         }
 
         // Update `modifiedAt` meta
-        $meta['modifiedAt'] = new UTCDateTime();
+        // Using Carbon here for testability
+        $meta['modifiedAt'] = new UTCDateTime(Carbon::now()->getPreciseTimestamp(3));
 
         // join meta data with response
         return CachedData::from(collect($meta + $scraperResponse));
diff --git a/tests/Unit/DefaultCachedScraperServiceTest.php b/tests/Unit/DefaultCachedScraperServiceTest.php
new file mode 100644
index 0000000..2e64d21
--- /dev/null
+++ b/tests/Unit/DefaultCachedScraperServiceTest.php
@@ -0,0 +1,142 @@
+<?php
+
+namespace Unit;
+
+use App\Contracts\Repository;
+use App\Services\DefaultCachedScraperService;
+use Illuminate\Support\Carbon;
+use Jenssegers\Mongodb\Eloquent\Builder;
+use Jikan\MyAnimeList\MalClient;
+use JMS\Serializer\SerializerInterface;
+use Mockery;
+use MongoDB\BSON\UTCDateTime;
+use Tests\TestCase;
+
+final class DefaultCachedScraperServiceTest extends TestCase
+{
+    public function tearDown(): void
+    {
+        Mockery::close();
+        // reset time pinning
+        Carbon::setTestNow();
+    }
+
+    private function requestHash(): string
+    {
+        return sha1("asdf");
+    }
+
+    private function makeCtorArgMocks(int $repositoryWhereCallCount = 1): array
+    {
+        $queryBuilderMock = Mockery::mock(Builder::class)->makePartial();
+        $repositoryMock = Mockery::mock(Repository::class);
+        $serializerMock = Mockery::mock(SerializerInterface::class);
+
+        $repositoryMock
+            ->expects()
+            ->where("request_hash", $this->requestHash())
+            ->times($repositoryWhereCallCount)
+            ->andReturn($queryBuilderMock);
+
+        return [
+            $queryBuilderMock,
+            $repositoryMock,
+            $serializerMock
+        ];
+    }
+
+    public function testIfFindListReturnsNotExpiredItems()
+    {
+        $testRequestHash = $this->requestHash();
+        // the cached data in the database
+        $dummyResults = collect([
+            ["dummy" => "dummy1", "modifiedAt" => new UTCDateTime()],
+            ["dummy" => "dummy2", "modifiedAt" => new UTCDateTime()]
+        ]);
+        [$queryBuilderMock, $repositoryMock, $serializerMock] = $this->makeCtorArgMocks();
+        $queryBuilderMock->expects()->get()->once()->andReturn($dummyResults);
+
+        $target = new DefaultCachedScraperService($repositoryMock, new MalClient(), $serializerMock);
+
+        $result = $target->findList($testRequestHash, fn() => []);
+
+        $this->assertEquals($dummyResults->toArray(), $result->toArray());
+    }
+
+    public function testIfFindListUpdatesCacheIfItemsExpired()
+    {
+        $testRequestHash = $this->requestHash();
+        $now = Carbon::now();
+        Carbon::setTestNow($now);
+
+        // the cached data in the database
+        $dummyResults = collect([
+            ["dummy" => "dummy1", "modifiedAt" => new UTCDateTime($now->sub("2 days")->timestamp)],
+            ["dummy" => "dummy2", "modifiedAt" => new UTCDateTime($now->sub("2 days")->timestamp)]
+        ]);
+
+        // the data returned by the scraper
+        $scraperData = [
+            "results" => [
+                ["dummy" => "dummy1"],
+                ["dummy" => "dummy2"]
+            ]
+        ];
+        [$queryBuilderMock, $repositoryMock, $serializerMock] = $this->makeCtorArgMocks(3);
+        $queryBuilderMock->expects()->get()->twice()->andReturn($dummyResults);
+        $queryBuilderMock->expects()->update(Mockery::any())->once()->andReturn(1);
+
+        $serializerMock->allows([
+            "toArray" => $scraperData
+        ]);
+
+        $target = new DefaultCachedScraperService($repositoryMock, new MalClient(), $serializerMock);
+        $result = $target->findList($testRequestHash, fn() => []);
+
+        $this->assertEquals([
+            ["dummy" => "dummy1", "modifiedAt" => new UTCDateTime($now->getPreciseTimestamp(3))],
+            ["dummy" => "dummy2", "modifiedAt" => new UTCDateTime($now->getPreciseTimestamp(3))]
+        ], $result->toArray());
+    }
+
+    public function testIfFindListUpdatesCacheIfCacheIsEmpty()
+    {
+        $testRequestHash = $this->requestHash();
+        $now = Carbon::now();
+        Carbon::setTestNow($now);
+
+        // the data returned by the scraper
+        $scraperData = [
+            "results" => [
+                ["dummy" => "dummy1"],
+                ["dummy" => "dummy2"]
+            ]
+        ];
+
+        $cacheData = [
+            ["dummy" => "dummy1", "modifiedAt" => new UTCDateTime($now->getPreciseTimestamp(3))],
+            ["dummy" => "dummy2", "modifiedAt" => new UTCDateTime($now->getPreciseTimestamp(3))]
+        ];
+
+        [$queryBuilderMock, $repositoryMock, $serializerMock] = $this->makeCtorArgMocks(2);
+        // at first the cache is empty
+        $queryBuilderMock->expects()->get()->once()->andReturn(collect());
+        // then it gets "inserted" into
+        $queryBuilderMock->expects()->get()->once()->andReturn(collect($cacheData));
+        $repositoryMock->expects()->insert(Mockery::any())->once()->andReturn(true);
+
+        $serializerMock->allows([
+            "toArray" => $scraperData
+        ]);
+
+        $target = new DefaultCachedScraperService($repositoryMock, new MalClient(), $serializerMock);
+        $result = $target->findList($testRequestHash, fn() => []);
+
+        $this->assertEquals($cacheData, $result->toArray());
+    }
+
+    public function testIfModifiedAtValueSetCorrectlyDuringCacheUpdate()
+    {
+
+    }
+}