diff --git a/.travis.yml b/.travis.yml
index e75c3c7..149c597 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,4 +14,5 @@ before_script:
     - composer install
 
 script:
+    - bin/console index:build
     - composer integrate
diff --git a/composer.json b/composer.json
index 00d51a4..53625ac 100644
--- a/composer.json
+++ b/composer.json
@@ -33,7 +33,8 @@
         "phpstan/phpstan": "^0.12.0",
         "phpactor/test-utils": "^1.0.2",
         "phpactor/console-extension": "^0.1.2",
-        "symfony/var-dumper": "^5.1"
+        "symfony/var-dumper": "^5.1",
+        "phpbench/phpbench": "^1.0"
     },
     "autoload": {
         "psr-4": {
@@ -55,7 +56,8 @@
         "integrate": [
             "vendor/bin/phpstan analyse",
             "vendor/bin/php-cs-fixer fix",
-            "vendor/bin/phpunit"
+            "vendor/bin/phpunit",
+            "vendor/bin/phpbench run"
         ]
     }
 }
diff --git a/lib/Adapter/Php/FileSearchIndex.php b/lib/Adapter/Php/FileSearchIndex.php
index ea43bbf..95f3c06 100644
--- a/lib/Adapter/Php/FileSearchIndex.php
+++ b/lib/Adapter/Php/FileSearchIndex.php
@@ -66,10 +66,19 @@ public function search(string $query): Generator
         }
     }
 
+    public function remove(Record $record): void
+    {
+        if (!isset($this->subjects[$this->recordKey($record)])) {
+            return;
+        }
+
+        unset($this->subjects[$this->recordKey($record)]);
+    }
+
     public function write(Record $record): void
     {
         $this->open();
-        $this->subjects[$record->recordType().$record->identifier()] = [$record->recordType(), $record->identifier()];
+        $this->subjects[$this->recordKey($record)] = [$record->recordType(), $record->identifier()];
 
         if (++$this->counter % self::BATCH_SIZE === 0) {
             $this->flush();
@@ -107,4 +116,9 @@ private function open(): void
 
         $this->initialized = true;
     }
+
+    private function recordKey(Record $record): string
+    {
+        return $record->recordType().$record->identifier();
+    }
 }
diff --git a/lib/Adapter/Php/InMemory/InMemoryIndex.php b/lib/Adapter/Php/InMemory/InMemoryIndex.php
index ae21a2d..37e290f 100644
--- a/lib/Adapter/Php/InMemory/InMemoryIndex.php
+++ b/lib/Adapter/Php/InMemory/InMemoryIndex.php
@@ -5,21 +5,13 @@
 use Generator;
 use Phpactor\Indexer\Model\Index;
 use Phpactor\Indexer\Model\IndexQueryAgent;
-use RuntimeException;
-use Phpactor\Indexer\Model\Record\FunctionRecord;
-use Phpactor\Indexer\Model\Record\ClassRecord;
 use Phpactor\Indexer\Model\Record;
 use SplFileInfo;
 
 class InMemoryIndex implements Index
 {
     /**
-     * @var InMemoryRepository
-     */
-    private $repository;
-
-    /**
-     * @var int
+     * @var int|null
      */
     private $lastUpdate;
 
@@ -28,11 +20,19 @@ class InMemoryIndex implements Index
      */
     private $searchIndex;
 
-    public function __construct(?InMemoryRepository $repository = null)
+    /**
+     * @var array<Record>
+     */
+    private $index;
+
+    /**
+     * @param array<Record> $index
+     */
+    public function __construct(array $index = [])
     {
-        $this->repository = $repository ?: new InMemoryRepository();
         $this->searchIndex = new InMemorySearchIndex();
         $this->lastUpdate = 0;
+        $this->index = $index;
     }
 
     public function lastUpdate(): int
@@ -47,43 +47,20 @@ public function query(): IndexQueryAgent
 
     public function write(Record $record): void
     {
+        $this->index[$this->recordKey($record)] = $record;
         $this->searchIndex->write($record);
-
-        if ($record instanceof ClassRecord) {
-            $this->repository->putClass($record);
-            return;
-        }
-
-        if ($record instanceof FunctionRecord) {
-            $this->repository->putFunction($record);
-            return;
-        }
-
-        throw new RuntimeException(sprintf(
-            'Do not know how to index "%s"',
-            get_class($record)
-        ));
     }
 
-    /**
-     * {@inheritDoc}
-     */
     public function get(Record $record): Record
     {
-        if ($record instanceof ClassRecord) {
-            // @phpstan-ignore-next-line
-            return $this->repository->getClass($record->fqn()) ?? $record;
-        }
+        $key = $this->recordKey($record);
 
-        if ($record instanceof FunctionRecord) {
-            // @phpstan-ignore-next-line
-            return $this->repository->getFunction($record->fqn()) ?? $record;
+        if (isset($this->index[$key])) {
+            /** @phpstan-ignore-next-line */
+            return $this->index[$key];
         }
 
-        throw new RuntimeException(sprintf(
-            'Do not know how to index "%s"',
-            get_class($record)
-        ));
+        return $record;
     }
 
     public function isFresh(SplFileInfo $fileInfo): bool
@@ -93,22 +70,22 @@ public function isFresh(SplFileInfo $fileInfo): bool
 
     public function reset(): void
     {
-        $this->repository->reset();
+        $this->index = [];
     }
 
     public function exists(): bool
     {
-        return $this->repository->lastUpdate !== 0;
+        return $this->lastUpdate !== 0;
     }
 
     public function done(): void
     {
-        $this->repository->lastUpdate = time();
+        $this->lastUpdate = time();
     }
 
     public function has(Record $record): bool
     {
-        return false;
+        return isset($this->index[$this->recordKey($record)]);
     }
 
     /**
@@ -118,4 +95,9 @@ public function search(string $search): Generator
     {
         yield from $this->searchIndex->search($search);
     }
+
+    private function recordKey(Record $record): string
+    {
+        return $record->recordType().$record->identifier();
+    }
 }
diff --git a/lib/Adapter/Php/InMemory/InMemoryRepository.php b/lib/Adapter/Php/InMemory/InMemoryRepository.php
deleted file mode 100644
index a25a7ca..0000000
--- a/lib/Adapter/Php/InMemory/InMemoryRepository.php
+++ /dev/null
@@ -1,58 +0,0 @@
-<?php
-
-namespace Phpactor\Indexer\Adapter\Php\InMemory;
-
-use Phpactor\Indexer\Model\Record\ClassRecord;
-use Phpactor\Indexer\Model\Record\FunctionRecord;
-
-class InMemoryRepository
-{
-    /**
-     * @var array<ClassRecord>
-     */
-    private $classes = [];
-
-    /**
-     * @var array<FunctionRecord>
-     */
-    private $functions = [];
-
-    /**
-     * @var int
-     */
-    public $lastUpdate = 0;
-
-    public function putClass(ClassRecord $class): void
-    {
-        $this->classes[$class->fqn()->__toString()] = $class;
-    }
-
-    public function putFunction(FunctionRecord $function): void
-    {
-        $this->functions[$function->fqn()->__toString()] = $function;
-    }
-
-    public function getClass(string $fqn): ?ClassRecord
-    {
-        if (!isset($this->classes[$fqn])) {
-            return null;
-        }
-
-        return $this->classes[$fqn];
-    }
-
-    public function reset(): void
-    {
-        $this->classes = [];
-        $this->functions = [];
-    }
-
-    public function getFunction(string $fqn): ?FunctionRecord
-    {
-        if (!isset($this->functions[$fqn])) {
-            return null;
-        }
-
-        return $this->functions[$fqn];
-    }
-}
diff --git a/lib/Adapter/Php/InMemory/InMemorySearchIndex.php b/lib/Adapter/Php/InMemory/InMemorySearchIndex.php
index 122fcb1..ad17ed0 100644
--- a/lib/Adapter/Php/InMemory/InMemorySearchIndex.php
+++ b/lib/Adapter/Php/InMemory/InMemorySearchIndex.php
@@ -33,7 +33,17 @@ public function write(Record $record): void
         $this->buffer[$record->identifier()] = [$record->recordType(), $record->identifier()];
     }
 
+    public function has(Record $record): bool
+    {
+        return isset($this->buffer[$record->identifier()]);
+    }
+
     public function flush(): void
     {
     }
+
+    public function remove(Record $record): void
+    {
+        unset($this->buffer[$record->identifier()]);
+    }
 }
diff --git a/lib/Model/SearchIndex.php b/lib/Model/SearchIndex.php
index 4e0ce88..b675f9a 100644
--- a/lib/Model/SearchIndex.php
+++ b/lib/Model/SearchIndex.php
@@ -13,5 +13,7 @@ public function search(string $query): Generator;
 
     public function write(Record $record): void;
 
+    public function remove(Record $record): void;
+
     public function flush(): void;
 }
diff --git a/lib/Model/SearchIndex/FilteredSearchIndex.php b/lib/Model/SearchIndex/FilteredSearchIndex.php
index cc39a89..54d0be9 100644
--- a/lib/Model/SearchIndex/FilteredSearchIndex.php
+++ b/lib/Model/SearchIndex/FilteredSearchIndex.php
@@ -49,4 +49,9 @@ public function flush(): void
     {
         $this->innerIndex->flush();
     }
+
+    public function remove(Record $record): void
+    {
+        $this->innerIndex->remove($record);
+    }
 }
diff --git a/lib/Model/SearchIndex/ValidatingSearchIndex.php b/lib/Model/SearchIndex/ValidatingSearchIndex.php
new file mode 100644
index 0000000..e839722
--- /dev/null
+++ b/lib/Model/SearchIndex/ValidatingSearchIndex.php
@@ -0,0 +1,70 @@
+<?php
+
+namespace Phpactor\Indexer\Model\SearchIndex;
+
+use Generator;
+use Phpactor\Indexer\Model\Index;
+use Phpactor\Indexer\Model\Record;
+use Phpactor\Indexer\Model\Record\HasPath;
+use Phpactor\Indexer\Model\SearchIndex;
+
+class ValidatingSearchIndex implements SearchIndex
+{
+    /**
+     * @var SearchIndex
+     */
+    private $innerIndex;
+
+    /**
+     * @var Index
+     */
+    private $index;
+
+    public function __construct(SearchIndex $innerIndex, Index $index)
+    {
+        $this->innerIndex = $innerIndex;
+        $this->index = $index;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function search(string $query): Generator
+    {
+        foreach ($this->innerIndex->search($query) as $result) {
+            if (!$this->index->has($result)) {
+                $this->innerIndex->remove($result);
+                continue;
+            }
+
+            $record = $this->index->get($result);
+
+            if (!$record instanceof HasPath) {
+                yield $result;
+                return;
+            }
+
+            if (!file_exists($record->filePath())) {
+                $this->innerIndex->remove($record);
+                continue;
+            }
+
+            yield $result;
+        }
+    }
+
+    public function write(Record $record): void
+    {
+        $this->innerIndex->write($record);
+    }
+
+    public function remove(Record $record): void
+    {
+        $this->innerIndex->remove($record);
+    }
+
+    public function flush(): void
+    {
+        $this->innerIndex->flush();
+    }
+}
diff --git a/tests/Benchmark/SearchBench.php b/tests/Benchmark/SearchBench.php
new file mode 100644
index 0000000..a3ed681
--- /dev/null
+++ b/tests/Benchmark/SearchBench.php
@@ -0,0 +1,71 @@
+<?php
+
+namespace Phpactor\Indexer\Tests\Benchmark;
+
+use Phpactor\Indexer\Adapter\Php\FileSearchIndex;
+use Phpactor\Indexer\Adapter\Php\Serialized\FileRepository;
+use Phpactor\Indexer\Adapter\Php\Serialized\SerializedIndex;
+use Phpactor\Indexer\Model\Matcher\ClassShortNameMatcher;
+use Phpactor\Indexer\Model\SearchIndex;
+use Phpactor\Indexer\Model\SearchIndex\ValidatingSearchIndex;
+
+/**
+ * Run ./bin/console index:build before running this benchmark
+ *
+ * @Iterations(10)
+ * @Revs(1)
+ * @OutputTimeUnit("seconds")
+ */
+class SearchBench
+{
+    /**
+     * @var SearchIndex
+     */
+    private $search;
+
+    public function createFileSearch(): void
+    {
+        $indexPath = __DIR__ . '/../..';
+        $this->search = new FileSearchIndex($indexPath . '/cache/search', new ClassShortNameMatcher());
+    }
+
+    public function createValidatingFileSearch(): void
+    {
+        $indexPath = __DIR__ . '/../../cache';
+        $this->search = new ValidatingSearchIndex(
+            new FileSearchIndex($indexPath . '/search', new ClassShortNameMatcher()),
+            new SerializedIndex(new FileRepository($indexPath))
+        );
+    }
+
+    /**
+     * @BeforeMethods({"createFileSearch"})
+     * @ParamProviders({"provideSearches"})
+     */
+    public function benchFileSearch(array $params): void
+    {
+        foreach ($this->search->search($params['search']) as $result) {
+        }
+    }
+
+    /**
+     * @BeforeMethods({"createValidatingFileSearch"})
+     * @ParamProviders({"provideSearches"})
+     */
+    public function benchValidatingFileSearch(array $params): void
+    {
+        foreach ($this->search->search($params['search']) as $result) {
+        }
+    }
+
+    public function provideSearches()
+    {
+        yield 'A' => [
+            'search' => 'A',
+        ];
+
+        yield 'Request' => [
+            'search' => 'Request',
+        ];
+    }
+}
diff --git a/tests/Unit/Model/SearchIndex/ValidatingSearchIndexTest.php b/tests/Unit/Model/SearchIndex/ValidatingSearchIndexTest.php
new file mode 100644
index 0000000..5318e1a
--- /dev/null
+++ b/tests/Unit/Model/SearchIndex/ValidatingSearchIndexTest.php
@@ -0,0 +1,87 @@
+<?php
+
+namespace Phpactor\Indexer\Tests\Unit\Model\SearchIndex;
+
+use Generator;
+use PHPUnit\Framework\TestCase;
+use Phpactor\Indexer\Adapter\Php\InMemory\InMemoryIndex;
+use Phpactor\Indexer\Adapter\Php\InMemory\InMemorySearchIndex;
+use Phpactor\Indexer\Model\Record\ClassRecord;
+use Phpactor\Indexer\Model\Record\MemberRecord;
+use Phpactor\Indexer\Model\SearchIndex\ValidatingSearchIndex;
+use Phpactor\Indexer\Tests\IntegrationTestCase;
+
+class ValidatingSearchIndexTest extends IntegrationTestCase
+{
+    /**
+     * @var InMemorySearchIndex
+     */
+    private $innerSearchIndex;
+    /**
+     * @var InMemoryIndex
+     */
+    private $index;
+
+    /**
+     * @var ValidatingSearchIndex
+     */
+    private $searchIndex;
+
+    protected function setUp(): void
+    {
+        $this->innerSearchIndex = new InMemorySearchIndex();
+        $this->index = new InMemoryIndex();
+        $this->searchIndex = new ValidatingSearchIndex(
+            $this->innerSearchIndex,
+            $this->index
+        );
+    }
+
+    public function testWillRemoveResultIfNotExistIndex(): void
+    {
+        $record = ClassRecord::fromName('Foobar');
+        $this->innerSearchIndex->write($record);
+
+        self::assertSearchCount(0, $this->searchIndex->search('Foobar'));
+        self::assertFalse($this->innerSearchIndex->has($record));
+    }
+
+    public function testYieldsRecordsWithoutAPath(): void
+    {
+        $record = MemberRecord::fromIdentifier('method#foo');
+        $this->index->write($record);
+        $this->innerSearchIndex->write($record);
+
+        self::assertSearchCount(1, $this->searchIndex->search('method#foo'));
+    }
+
+    public function testRemovesFromIndexIfFileDoesNotExist(): void
+    {
+        $record = ClassRecord::fromName('Foobar')
+            ->setFilePath($this->workspace()->path('nope.php'));
+
+        $this->index->write($record);
+        $this->innerSearchIndex->write($record);
+
+        self::assertSearchCount(0, $this->searchIndex->search('Foobar'));
+        self::assertFalse($this->innerSearchIndex->has($record));
+    }
+
+    public function testYieldsSearchResultIfFileExists(): void
+    {
+        $this->workspace()->put('yep.php', 'foo');
+        $record = ClassRecord::fromName('Foobar')
+            ->setFilePath($this->workspace()->path('yep.php'));
+
+        $this->index->write($record);
+        $this->innerSearchIndex->write($record);
+
+        self::assertSearchCount(1, $this->searchIndex->search('Foobar'));
+        self::assertTrue($this->innerSearchIndex->has($record));
+    }
+
+    private static function assertSearchCount(int $int, Generator $generator): void
+    {
+        self::assertEquals($int, count(iterator_to_array($generator)));
+    }
+}