diff --git a/tests/Db/SQLite3/TestDbDriverSQLite3.php b/tests/Db/SQLite3/TestDbDriverSQLite3.php
index 57bc3f29..1dba8fec 100644
--- a/tests/Db/SQLite3/TestDbDriverSQLite3.php
+++ b/tests/Db/SQLite3/TestDbDriverSQLite3.php
@@ -11,6 +11,9 @@ class TestDbDriverSQLite3 extends \PHPUnit\Framework\TestCase {
     protected $ch;
 
     function setUp() {
+        if(!extension_loaded("sqlite3")) {
+            $this->markTestSkipped("SQLite extension not loaded");
+        }
         $this->clearData();
         $conf = new Conf();
         $conf->dbDriver = Db\SQLite3\Driver::class;
diff --git a/tests/Db/SQLite3/TestDbResultSQLite3.php b/tests/Db/SQLite3/TestDbResultSQLite3.php
index 33d46e1e..73d530ba 100644
--- a/tests/Db/SQLite3/TestDbResultSQLite3.php
+++ b/tests/Db/SQLite3/TestDbResultSQLite3.php
@@ -9,6 +9,9 @@ class TestDbResultSQLite3 extends \PHPUnit\Framework\TestCase {
     protected $c;
 
     function setUp() {
+        if(!extension_loaded("sqlite3")) {
+            $this->markTestSkipped("SQLite extension not loaded");
+        }
         $c = new \SQLite3(":memory:");
         $c->enableExceptions(true);
         $this->c = $c;
diff --git a/tests/Db/SQLite3/TestDbStatementSQLite3.php b/tests/Db/SQLite3/TestDbStatementSQLite3.php
index f6accc9d..b45aaf45 100644
--- a/tests/Db/SQLite3/TestDbStatementSQLite3.php
+++ b/tests/Db/SQLite3/TestDbStatementSQLite3.php
@@ -11,6 +11,9 @@ class TestDbStatementSQLite3 extends \PHPUnit\Framework\TestCase {
     static protected $imp = Db\SQLite3\Statement::class;
 
     function setUp() {
+        if(!extension_loaded("sqlite3")) {
+            $this->markTestSkipped("SQLite extension not loaded");
+        }
         $c = new \SQLite3(":memory:");
         $c->enableExceptions(true);
         $this->c = $c;
diff --git a/tests/Db/SQLite3/TestDbUpdateSQLite3.php b/tests/Db/SQLite3/TestDbUpdateSQLite3.php
index 3fe66d71..0aee2020 100644
--- a/tests/Db/SQLite3/TestDbUpdateSQLite3.php
+++ b/tests/Db/SQLite3/TestDbUpdateSQLite3.php
@@ -16,6 +16,9 @@ class TestDbUpdateSQLite3 extends \PHPUnit\Framework\TestCase {
     const MINIMAL2 = "pragma user_version=2";
 
     function setUp() {
+        if(!extension_loaded("sqlite3")) {
+            $this->markTestSkipped("SQLite extension not loaded");
+        }
         $this->clearData();
         $this->vfs = vfsStream::setup("schemata", null, ['SQLite3' => []]);
         $conf = new Conf();
diff --git a/tests/Feed/TestFeed.php b/tests/Feed/TestFeed.php
index 5e4d1f6c..c78181cd 100644
--- a/tests/Feed/TestFeed.php
+++ b/tests/Feed/TestFeed.php
@@ -8,19 +8,10 @@ class TestFeed extends \PHPUnit\Framework\TestCase {
     use Test\Tools;
 
     protected static $host = "http://localhost:8000/";
-    protected static $serverUp = true;
     protected $base = "";
-    
-    function time(string $t): string {
-        return gmdate("D, d M Y H:i:s \G\M\T", strtotime($t));
-    }
-
-    static function setUpBeforeClass() {
-        if(!@file_get_contents(self::$host."IsUp")) self::$serverUp = false;
-    }
 
     function setUp() {
-        if(!self::$serverUp) {
+        if(!@file_get_contents(self::$host."IsUp")) {
             $this->markTestSkipped("Test Web server is not accepting requests");
         }
         $this->base = self::$host."Feed/";
@@ -28,6 +19,23 @@ class TestFeed extends \PHPUnit\Framework\TestCase {
         Data::$conf = new Conf();
     }
 
+    function testHandleCacheHeaders() {
+        $t = time();
+        $e = "78567a";
+        $f = new Feed(null, $this->base."Caching/304Random", $this->dateTransform($t, "http"), $e);
+        $this->assertTime($t, $f->lastModified);
+        $this->assertSame($e, $f->resource->getETag());
+        $f = new Feed(null, $this->base."Caching/304ETagOnly", $this->dateTransform($t, "http"), $e);
+        $this->assertTime($t, $f->lastModified);
+        $this->assertSame($e, $f->resource->getETag());
+        $f = new Feed(null, $this->base."Caching/304LastModOnly", $this->dateTransform($t, "http"), $e);
+        $this->assertTime($t, $f->lastModified);
+        $this->assertSame($e, $f->resource->getETag());
+        $f = new Feed(null, $this->base."Caching/304None", $this->dateTransform($t, "http"), $e);
+        $this->assertTime($t, $f->lastModified);
+        $this->assertSame($e, $f->resource->getETag());
+    }
+    
     function testComputeNextFetchOnError() {
         for($a = 0; $a < 100; $a++) {
             if($a < 3) {
diff --git a/tests/docroot/Feed/Caching/304ETagOnly.php b/tests/docroot/Feed/Caching/304ETagOnly.php
new file mode 100644
index 00000000..2b482dd8
--- /dev/null
+++ b/tests/docroot/Feed/Caching/304ETagOnly.php
@@ -0,0 +1,7 @@
+<?php return [
+    'code'    => 304,
+    'cache'   => false,
+    'fields'  => [
+        "ETag: ".$_SERVER['HTTP_IF_NONE_MATCH'],
+    ],
+];
\ No newline at end of file
diff --git a/tests/docroot/Feed/Caching/304LastModOnly.php b/tests/docroot/Feed/Caching/304LastModOnly.php
new file mode 100644
index 00000000..444ccdbc
--- /dev/null
+++ b/tests/docroot/Feed/Caching/304LastModOnly.php
@@ -0,0 +1,7 @@
+<?php return [
+    'code'    => 304,
+    'cache'   => false,
+    'fields'  => [
+        'Last-Modified: '.$_SERVER['HTTP_IF_MODIFIED_SINCE'],
+    ],
+];
\ No newline at end of file
diff --git a/tests/docroot/Feed/Caching/304None.php b/tests/docroot/Feed/Caching/304None.php
new file mode 100644
index 00000000..f8dcef02
--- /dev/null
+++ b/tests/docroot/Feed/Caching/304None.php
@@ -0,0 +1,4 @@
+<?php return [
+    'code'    => 304,
+    'cache'   => false,
+];
\ No newline at end of file
diff --git a/tests/docroot/Feed/Caching/304Random.php b/tests/docroot/Feed/Caching/304Random.php
new file mode 100644
index 00000000..c01917e3
--- /dev/null
+++ b/tests/docroot/Feed/Caching/304Random.php
@@ -0,0 +1,7 @@
+<?php return [
+    'code'    => 304,
+    'lastMod' => random_int(0,2^31),
+    'fields' => [
+        "ETag: ".bin2hex(random_bytes(8)),
+    ],
+];
\ No newline at end of file
diff --git a/tests/lib/Database/DriverSQLite3.php b/tests/lib/Database/DriverSQLite3.php
index d1e9fa31..b78fefdc 100644
--- a/tests/lib/Database/DriverSQLite3.php
+++ b/tests/lib/Database/DriverSQLite3.php
@@ -6,6 +6,9 @@ use JKingWeb\Arsse\Db\SQLite3\Driver;
 
 trait DriverSQLite3 {
     function setUpDriver() {
+        if(!extension_loaded("sqlite3")) {
+            $this->markTestSkipped("SQLite extension not loaded");
+        }
         Data::$conf->dbSQLite3File = ":memory:";
         $this->drv = new Driver(true);
     }
diff --git a/tests/server.php b/tests/server.php
index c80b14d8..9f4b062e 100644
--- a/tests/server.php
+++ b/tests/server.php
@@ -54,7 +54,7 @@ http_response_code((int) $response['code']);
 // if the response has a body, set the content type and (possibly) the ETag.
 if(strlen($response['content'])) {
     header("Content-Type: ".$response['mime']);
-    if($response['cache']) header("ETag: ".md5($response['content']));
+    if($response['cache']) header('ETag: "'.md5($response['content']).'"');
 }
 // if caching is enabled, set the last-modified date
 if($response['cache']) header("Last-Modified: ".gmdate("D, d M Y H:i:s \G\M\T", $response['lastMod']));
diff --git a/tests/test b/tests/test
index 4e18ac21..134b98d8 100755
--- a/tests/test
+++ b/tests/test
@@ -1,7 +1,7 @@
 #! /bin/sh
 base=`dirname "$0"`
 php -n -S localhost:8000 "$base/server.php"  >/dev/null &
-php "$base/../vendor/phpunit/phpunit/phpunit" -c "$base/phpunit.xml"
+php "$base/../vendor/phpunit/phpunit/phpunit" -c "$base/phpunit.xml" $*
 sleep 1s
 pid=`lsof -n -i:8000 | grep -Eo "php\s+[0-9]+" | grep -Eo "[0-9]+"`
 kill $pid
\ No newline at end of file
diff --git a/tests/test.bat b/tests/test.bat
index 21ff7fd4..12854932 100644
--- a/tests/test.bat
+++ b/tests/test.bat
@@ -2,7 +2,7 @@
 setlocal
 set base=%~dp0
 start /b php -n -S localhost:8000 "%base%\server.php" >nul
-php "%base%\..\vendor\phpunit\phpunit\phpunit" -c "%base%\phpunit.xml"
+php "%base%\..\vendor\phpunit\phpunit\phpunit" -c "%base%\phpunit.xml" %*
 timeout /nobreak /t 1 >nul
 for /f "usebackq tokens=5" %%a in (`netstat -aon ^| find "LISTENING" ^| find ":8000"`) do (
     taskkill /f /pid %%a >nul