diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index e1d7b04..e439c87 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,10 +1,11 @@
 <?xml version="1.0"?>
-<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" bootstrap="test/Horde/Stream/Filter/bootstrap.php" colors="true" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.3/phpunit.xsd">
-  <coverage>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" bootstrap="vendor/autoload.php" colors="true" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/11.0/phpunit.xsd">
+  <source>
     <include>
       <directory suffix=".php">lib</directory>
+      <directory suffix=".php">src</directory>
     </include>
-  </coverage>
+  </source>
   <testsuites>
     <testsuite name="horde/Stream/Filter">
       <directory>test</directory>
diff --git a/src/Bin2hex.php b/src/Bin2hex.php
new file mode 100644
index 0000000..a360ae3
--- /dev/null
+++ b/src/Bin2hex.php
@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright 2011-2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @author Michael Slusarz <slusarz@horde.org>
+ */
+
+namespace Horde\Stream\Filter;
+
+use php_user_filter;
+
+class Bin2hex extends php_user_filter
+{
+    public const FILTER_NAME = 'horde.stream.filter.bin2hex';
+
+    public static function register(): void
+    {
+        if (in_array(self::FILTER_NAME, stream_get_filters())) {
+            return;
+        }
+        stream_filter_register(self::FILTER_NAME, static::class);
+    }
+
+    public function filter($in, $out, &$consumed, $closing): int
+    {
+        while ($bucket = stream_bucket_make_writeable($in)) {
+            $bucket->data = bin2hex($bucket->data);
+            $consumed += $bucket->datalen;
+            stream_bucket_append($out, $bucket);
+        }
+
+        return PSFS_PASS_ON;
+    }
+}
diff --git a/src/Crc32.php b/src/Crc32.php
new file mode 100644
index 0000000..8d2e42e
--- /dev/null
+++ b/src/Crc32.php
@@ -0,0 +1,114 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright 2011-2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @author Michael Slusarz <slusarz@horde.org>
+ */
+
+namespace Horde\Stream\Filter;
+
+use php_user_filter;
+
+class Crc32 extends php_user_filter
+{
+    public const FILTER_NAME = 'horde.stream.filter.crc32';
+
+    public static function register(): void
+    {
+        if (in_array(self::FILTER_NAME, stream_get_filters())) {
+            return;
+        }
+        stream_filter_register(self::FILTER_NAME, static::class);
+    }
+
+    public function onCreate(): bool
+    {
+        $this->params->crc32 = 0;
+
+        return true;
+    }
+
+    public function filter($in, $out, &$consumed, $closing): int
+    {
+        while ($bucket = stream_bucket_make_writeable($in)) {
+            $consumed += $bucket->datalen;
+            $this->params->crc32 = $this->crc32Combine(
+                $this->params->crc32,
+                crc32($bucket->data),
+                $bucket->datalen,
+            );
+            stream_bucket_append($out, $bucket);
+        }
+
+        return PSFS_PASS_ON;
+    }
+
+    private function crc32Combine(int $crc1, int $crc2, int $len2): int
+    {
+        $odd = [0xedb88320];
+        $row = 1;
+
+        for ($n = 1; $n < 32; ++$n) {
+            $odd[$n] = $row;
+            $row <<= 1;
+        }
+
+        $this->gf2MatrixSquare($even, $odd);
+        $this->gf2MatrixSquare($odd, $even);
+
+        do {
+            $this->gf2MatrixSquare($even, $odd);
+
+            if ($len2 & 1) {
+                $crc1 = $this->gf2MatrixTimes($even, $crc1);
+            }
+
+            $len2 >>= 1;
+
+            if ($len2 === 0) {
+                break;
+            }
+
+            $this->gf2MatrixSquare($odd, $even);
+            if ($len2 & 1) {
+                $crc1 = $this->gf2MatrixTimes($odd, $crc1);
+            }
+
+            $len2 >>= 1;
+        } while ($len2 !== 0);
+
+        $crc1 ^= $crc2;
+
+        return $crc1;
+    }
+
+    private function gf2MatrixSquare(?array &$square, array &$mat): void
+    {
+        $square = [];
+        for ($n = 0; $n < 32; ++$n) {
+            $square[$n] = $this->gf2MatrixTimes($mat, $mat[$n]);
+        }
+    }
+
+    private function gf2MatrixTimes(array $mat, int $vec): int
+    {
+        $i = $sum = 0;
+
+        while ($vec) {
+            if ($vec & 1) {
+                $sum ^= $mat[$i];
+            }
+
+            $vec = ($vec >> 1) & 0x7FFFFFFF;
+            ++$i;
+        }
+
+        return $sum;
+    }
+}
diff --git a/src/Eol.php b/src/Eol.php
new file mode 100644
index 0000000..7106fed
--- /dev/null
+++ b/src/Eol.php
@@ -0,0 +1,78 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright 2009-2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @author Michael Slusarz <slusarz@horde.org>
+ * @author Angelo Milazzo <bsod85@gmail.com>
+ */
+
+namespace Horde\Stream\Filter;
+
+use php_user_filter;
+
+class Eol extends php_user_filter
+{
+    public const FILTER_NAME = 'horde.stream.filter.eol';
+
+    /** @var string[] */
+    private array $search = [];
+
+    private string|array $replace = '';
+
+    private string $prependNext = '';
+
+    public static function register(): void
+    {
+        if (in_array(self::FILTER_NAME, stream_get_filters())) {
+            return;
+        }
+        stream_filter_register(self::FILTER_NAME, static::class);
+    }
+
+    public function onCreate(): bool
+    {
+        $eol = $this->params['eol'] ?? "\r\n";
+
+        if (!strlen($eol)) {
+            $this->search = ["\r", "\n"];
+            $this->replace = '';
+        } elseif (in_array($eol, ["\r", "\n"])) {
+            $this->search = ["\r\n", ($eol === "\r") ? "\n" : "\r"];
+            $this->replace = $eol;
+        } else {
+            $this->search = ["\r\n", "\r", "\n"];
+            $this->replace = ["\n", "\n", $eol];
+        }
+
+        return true;
+    }
+
+    public function filter($in, $out, &$consumed, $closing): int
+    {
+        while ($bucket = stream_bucket_make_writeable($in)) {
+            $bucket->data = $this->prependNext . $bucket->data;
+            $this->prependNext = '';
+
+            if (
+                !$closing
+                && in_array("\r\n", $this->search)
+                && ($bucket->data[$bucket->datalen - 1] === "\r")
+            ) {
+                $bucket->data = substr($bucket->data, 0, -1);
+                $this->prependNext = "\r";
+            }
+
+            $bucket->data = str_replace($this->search, $this->replace, $bucket->data);
+            $consumed += $bucket->datalen;
+            stream_bucket_append($out, $bucket);
+        }
+
+        return PSFS_PASS_ON;
+    }
+}
diff --git a/src/Htmlspecialchars.php b/src/Htmlspecialchars.php
new file mode 100644
index 0000000..c69cb4d
--- /dev/null
+++ b/src/Htmlspecialchars.php
@@ -0,0 +1,40 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright 2012-2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @author Jan Schneider <jan@horde.org>
+ */
+
+namespace Horde\Stream\Filter;
+
+use php_user_filter;
+
+class Htmlspecialchars extends php_user_filter
+{
+    public const FILTER_NAME = 'horde.stream.filter.htmlspecialchars';
+
+    public static function register(): void
+    {
+        if (in_array(self::FILTER_NAME, stream_get_filters())) {
+            return;
+        }
+        stream_filter_register(self::FILTER_NAME, static::class);
+    }
+
+    public function filter($in, $out, &$consumed, $closing): int
+    {
+        while ($bucket = stream_bucket_make_writeable($in)) {
+            $bucket->data = htmlspecialchars($bucket->data);
+            $consumed += $bucket->datalen;
+            stream_bucket_append($out, $bucket);
+        }
+
+        return PSFS_PASS_ON;
+    }
+}
diff --git a/src/NullFilter.php b/src/NullFilter.php
new file mode 100644
index 0000000..b8a52be
--- /dev/null
+++ b/src/NullFilter.php
@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * Copyright 2012-2026 Horde LLC (http://www.horde.org/)
+ *
+ * See the enclosed file LICENSE for license information (LGPL). If you
+ * did not receive this file, see http://www.horde.org/licenses/lgpl21.
+ *
+ * @author Michael J Rubinsky <mrubinsk@horde.org>
+ */
+
+namespace Horde\Stream\Filter;
+
+use php_user_filter;
+
+class NullFilter extends php_user_filter
+{
+    public const FILTER_NAME = 'horde.stream.filter.null';
+
+    private string $search = "\0";
+
+    private string $replace = '';
+
+    public static function register(): void
+    {
+        if (in_array(self::FILTER_NAME, stream_get_filters())) {
+            return;
+        }
+        stream_filter_register(self::FILTER_NAME, static::class);
+    }
+
+    public function onCreate(): bool
+    {
+        $this->replace = $this->params->replace ?? '';
+
+        return true;
+    }
+
+    public function filter($in, $out, &$consumed, $closing): int
+    {
+        while ($bucket = stream_bucket_make_writeable($in)) {
+            $bucket->data = str_replace($this->search, $this->replace, $bucket->data);
+            $consumed += $bucket->datalen;
+            stream_bucket_append($out, $bucket);
+        }
+
+        return PSFS_PASS_ON;
+    }
+}
diff --git a/test/Horde/Stream/Filter/AllTests.php b/test/Horde/Stream/Filter/AllTests.php
deleted file mode 100644
index 6966fde..0000000
--- a/test/Horde/Stream/Filter/AllTests.php
+++ /dev/null
@@ -1,6 +0,0 @@
-<?php
-
-if (!class_exists('Horde_Test_AllTests')) {
-    require_once 'Horde/Test/AllTests.php';
-}
-Horde_Test_AllTests::init(__FILE__)->run();
diff --git a/test/Horde/Stream/Filter/Bin2hexTest.php b/test/Horde/Stream/Filter/Bin2hexTest.php
index 75f205a..3629741 100644
--- a/test/Horde/Stream/Filter/Bin2hexTest.php
+++ b/test/Horde/Stream/Filter/Bin2hexTest.php
@@ -1,46 +1,51 @@
 <?php
 
-/**
- * @category   Horde
- * @package    Stream_Filter
- * @subpackage UnitTests
- */
+declare(strict_types=1);
 
 namespace Horde\Stream\Filter;
 
-use Horde_Test_Case as TestCase;
+use Horde_Stream_Filter_Bin2hex;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
 
-/**
- * @category   Horde
- * @package    Stream_Filter
- * @subpackage UnitTests
- * @coversNothing
- */
+#[CoversClass(Bin2hex::class)]
 class Bin2hexTest extends TestCase
 {
-    public $fp;
-    public $testdata;
+    private string $testdata;
 
-    public function setup(): void
-    {
-        stream_filter_register('horde_bin2hex', 'Horde_Stream_Filter_Bin2hex');
+    /** @var resource */
+    private $fp;
 
+    public function setUp(): void
+    {
         $this->testdata = str_repeat("0123456789ABCDE", 1000);
-
         $this->fp = fopen('php://temp', 'r+');
         fwrite($this->fp, $this->testdata);
     }
 
-    public function testCrc32()
+    public function tearDown(): void
+    {
+        fclose($this->fp);
+    }
+
+    public function testLegacyBin2hex(): void
     {
+        @stream_filter_register('horde_bin2hex', Horde_Stream_Filter_Bin2hex::class);
         $filter = stream_filter_prepend($this->fp, 'horde_bin2hex', STREAM_FILTER_READ);
+        rewind($this->fp);
+
+        $this->assertEquals(bin2hex($this->testdata), stream_get_contents($this->fp));
+
+        stream_filter_remove($filter);
+    }
 
+    public function testModernBin2hex(): void
+    {
+        Bin2hex::register();
+        $filter = stream_filter_prepend($this->fp, Bin2hex::FILTER_NAME, STREAM_FILTER_READ);
         rewind($this->fp);
 
-        $this->assertEquals(
-            bin2hex($this->testdata),
-            stream_get_contents($this->fp)
-        );
+        $this->assertEquals(bin2hex($this->testdata), stream_get_contents($this->fp));
 
         stream_filter_remove($filter);
     }
diff --git a/test/Horde/Stream/Filter/Crc32Test.php b/test/Horde/Stream/Filter/Crc32Test.php
index 5bcbb4c..1cb36b0 100644
--- a/test/Horde/Stream/Filter/Crc32Test.php
+++ b/test/Horde/Stream/Filter/Crc32Test.php
@@ -1,39 +1,37 @@
 <?php
 
-/**
- * @category   Horde
- * @package    Stream_Filter
- * @subpackage UnitTests
- */
+declare(strict_types=1);
 
 namespace Horde\Stream\Filter;
 
-use Horde_Test_Case as TestCase;
+use Horde_Stream_Filter_Crc32;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
 use stdClass;
 
-/**
- * @category   Horde
- * @package    Stream_Filter
- * @subpackage UnitTests
- * @coversNothing
- */
+#[CoversClass(Crc32::class)]
 class Crc32Test extends TestCase
 {
-    public $fp;
-    public $testdata;
+    private string $testdata;
 
-    public function setup(): void
-    {
-        stream_filter_register('horde_crc32', 'Horde_Stream_Filter_Crc32');
+    /** @var resource */
+    private $fp;
 
+    public function setUp(): void
+    {
         $this->testdata = str_repeat("0123456789ABCDE", 1000);
-
         $this->fp = fopen('php://temp', 'r+');
         fwrite($this->fp, $this->testdata);
     }
 
-    public function testCrc32()
+    public function tearDown(): void
+    {
+        fclose($this->fp);
+    }
+
+    public function testLegacyCrc32(): void
     {
+        @stream_filter_register('horde_crc32', Horde_Stream_Filter_Crc32::class);
         $params = new stdClass();
         $filter = stream_filter_prepend($this->fp, 'horde_crc32', STREAM_FILTER_READ, $params);
 
@@ -41,12 +39,24 @@ public function testCrc32()
         while (fread($this->fp, 1024)) {
         }
 
-        $this->assertObjectHasAttribute('crc32', $params);
+        $this->assertTrue(property_exists($params, 'crc32'));
+        $this->assertEquals(crc32($this->testdata), $params->crc32);
+
+        stream_filter_remove($filter);
+    }
+
+    public function testModernCrc32(): void
+    {
+        Crc32::register();
+        $params = new stdClass();
+        $filter = stream_filter_prepend($this->fp, Crc32::FILTER_NAME, STREAM_FILTER_READ, $params);
+
+        rewind($this->fp);
+        while (fread($this->fp, 1024)) {
+        }
 
-        $this->assertEquals(
-            crc32($this->testdata),
-            $params->crc32
-        );
+        $this->assertTrue(property_exists($params, 'crc32'));
+        $this->assertEquals(crc32($this->testdata), $params->crc32);
 
         stream_filter_remove($filter);
     }
diff --git a/test/Horde/Stream/Filter/EolTest.php b/test/Horde/Stream/Filter/EolTest.php
index b2d4f4c..e6bdd7e 100644
--- a/test/Horde/Stream/Filter/EolTest.php
+++ b/test/Horde/Stream/Filter/EolTest.php
@@ -1,28 +1,24 @@
 <?php
 
-/**
- * @category   Horde
- * @package    Stream_Filter
- * @subpackage UnitTests
- */
+declare(strict_types=1);
 
 namespace Horde\Stream\Filter;
 
-use Horde_Test_Case as TestCase;
+use Horde_Stream_Filter_Eol;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\TestCase;
 
-/**
- * @category   Horde
- * @package    Stream_Filter
- * @subpackage UnitTests
- * @coversNothing
- */
+#[CoversClass(Eol::class)]
 class EolTest extends TestCase
 {
-    public $fp;
+    /** @var resource */
+    private $fp;
 
-    public function setup(): void
+    public function setUp(): void
     {
-        stream_filter_register('horde_eol', 'Horde_Stream_Filter_Eol');
+        @stream_filter_register('horde_eol', Horde_Stream_Filter_Eol::class);
+        Eol::register();
         $this->fp = fopen('php://temp', 'r+');
         fwrite($this->fp, "A\r\nB\rC\nD\r\n\r\nE\r\rF\n\nG\r\n\n\r\nH\r\n\r\r\nI");
     }
@@ -32,34 +28,40 @@ public function tearDown(): void
         fclose($this->fp);
     }
 
-    public static function lineEndingProvider()
+    public static function lineEndingProvider(): array
     {
         return [
-            ["\r", "A\rB\rC\rD\r\rE\r\rF\r\rG\r\r\rH\r\r\rI"],
-            ["\n", "A\nB\nC\nD\n\nE\n\nF\n\nG\n\n\nH\n\n\nI"],
-            ["\r\n", "A\r\nB\r\nC\r\nD\r\n\r\nE\r\n\r\nF\r\n\r\nG\r\n\r\n\r\nH\r\n\r\n\r\nI"],
-            ["", "ABCDEFGHI"],
+            'CR' => ["\r", "A\rB\rC\rD\r\rE\r\rF\r\rG\r\r\rH\r\r\rI"],
+            'LF' => ["\n", "A\nB\nC\nD\n\nE\n\nF\n\nG\n\n\nH\n\n\nI"],
+            'CRLF' => ["\r\n", "A\r\nB\r\nC\r\nD\r\n\r\nE\r\n\r\nF\r\n\r\nG\r\n\r\n\r\nH\r\n\r\n\r\nI"],
+            'strip' => ["", "ABCDEFGHI"],
         ];
     }
 
-    /**
-     * @dataProvider lineEndingProvider
-     */
-    public function testFilterLineEndings($eol, $expected)
+    #[DataProvider('lineEndingProvider')]
+    public function testLegacyFilterLineEndings(string $eol, string $expected): void
     {
         $filter = stream_filter_prepend($this->fp, 'horde_eol', STREAM_FILTER_READ, ['eol' => $eol]);
         rewind($this->fp);
         $this->assertEquals($expected, stream_get_contents($this->fp));
     }
 
-    public function testBug12673()
+    #[DataProvider('lineEndingProvider')]
+    public function testModernFilterLineEndings(string $eol, string $expected): void
+    {
+        $filter = stream_filter_prepend($this->fp, Eol::FILTER_NAME, STREAM_FILTER_READ, ['eol' => $eol]);
+        rewind($this->fp);
+        $this->assertEquals($expected, stream_get_contents($this->fp));
+    }
+
+    public function testBug12673(): void
     {
         $test = str_repeat(str_repeat("A", 1) . "\r\n", 4000);
 
         rewind($this->fp);
         fwrite($this->fp, $test);
 
-        $filter = stream_filter_prepend($this->fp, 'horde_eol', STREAM_FILTER_READ, ['eol' => "\r\n"]);
+        stream_filter_prepend($this->fp, Eol::FILTER_NAME, STREAM_FILTER_READ, ['eol' => "\r\n"]);
         rewind($this->fp);
 
         $this->assertEquals($test, stream_get_contents($this->fp));
@@ -70,7 +72,7 @@ public function testBug12673()
         ftruncate($this->fp, 0);
         fwrite($this->fp, $test);
 
-        stream_filter_prepend($this->fp, 'horde_eol', STREAM_FILTER_READ, ['eol' => "\r\n"]);
+        stream_filter_prepend($this->fp, Eol::FILTER_NAME, STREAM_FILTER_READ, ['eol' => "\r\n"]);
         rewind($this->fp);
 
         $this->assertEquals(
@@ -80,34 +82,26 @@ public function testBug12673()
                 . fread($this->fp, 1)
                 . fread($this->fp, 14)
                 . fread($this->fp, 2)
-                . fread($this->fp, 100)
+                . fread($this->fp, 100),
         );
     }
 
-    public function testUnixStyleNewLineSubstitution()
+    public function testUnixStyleNewLineSubstitution(): void
     {
         $test = str_repeat("A\r\n", 4000);
-        $expectedResult = str_repeat("A\n", 4000);
+        $expected = str_repeat("A\n", 4000);
 
         rewind($this->fp);
         fwrite($this->fp, $test);
 
-        $filter = stream_filter_prepend($this->fp, 'horde_eol', STREAM_FILTER_READ, ['eol' => "\n"]);
+        stream_filter_prepend($this->fp, Eol::FILTER_NAME, STREAM_FILTER_READ, ['eol' => "\n"]);
         rewind($this->fp);
 
-        $this->assertEquals($expectedResult, stream_get_contents($this->fp));
+        $this->assertEquals($expected, stream_get_contents($this->fp));
     }
 
-    /**
-     * Test CRLF split at bucket boundary (byte 8191).
-     *
-     * This is the specific case that PR #2 fixes. The \r from \r\n falls
-     * at the end of the first bucket (8192 bytes), causing incorrect
-     * double newline conversion in buggy implementation.
-     */
-    public function testCrlfBucketBoundarySplit()
+    public function testCrlfBucketBoundarySplit(): void
     {
-        // 2730 * 3 bytes = 8190 bytes, then X\r\n crosses boundary
         $test = str_repeat("A\r\n", 2730) . "X\r\n" . "END";
         $expected = str_repeat("A\n", 2730) . "X\n" . "END";
 
@@ -115,16 +109,13 @@ public function testCrlfBucketBoundarySplit()
         ftruncate($this->fp, 0);
         fwrite($this->fp, $test);
 
-        stream_filter_prepend($this->fp, 'horde_eol', STREAM_FILTER_READ, ['eol' => "\n"]);
+        stream_filter_prepend($this->fp, Eol::FILTER_NAME, STREAM_FILTER_READ, ['eol' => "\n"]);
         rewind($this->fp);
 
         $this->assertEquals($expected, stream_get_contents($this->fp));
     }
 
-    /**
-     * Test trailing bare \r at end of stream.
-     */
-    public function testTrailingCarriageReturn()
+    public function testTrailingCarriageReturn(): void
     {
         $test = "Line1\r\nLine2\r";
         $expected = "Line1\nLine2\n";
@@ -133,18 +124,13 @@ public function testTrailingCarriageReturn()
         ftruncate($this->fp, 0);
         fwrite($this->fp, $test);
 
-        stream_filter_prepend($this->fp, 'horde_eol', STREAM_FILTER_READ, ['eol' => "\n"]);
+        stream_filter_prepend($this->fp, Eol::FILTER_NAME, STREAM_FILTER_READ, ['eol' => "\n"]);
         rewind($this->fp);
 
         $this->assertEquals($expected, stream_get_contents($this->fp));
     }
 
-    /**
-     * Test conversion to CRLF (multi-character target EOL).
-     *
-     * Ensures original Bug #12673 fix still works.
-     */
-    public function testConversionToMultiCharEol()
+    public function testConversionToMultiCharEol(): void
     {
         $test = str_repeat("A\n", 4000);
         $expected = str_repeat("A\r\n", 4000);
@@ -153,16 +139,13 @@ public function testConversionToMultiCharEol()
         ftruncate($this->fp, 0);
         fwrite($this->fp, $test);
 
-        stream_filter_prepend($this->fp, 'horde_eol', STREAM_FILTER_READ, ['eol' => "\r\n"]);
+        stream_filter_prepend($this->fp, Eol::FILTER_NAME, STREAM_FILTER_READ, ['eol' => "\r\n"]);
         rewind($this->fp);
 
         $this->assertEquals($expected, stream_get_contents($this->fp));
     }
 
-    /**
-     * Test double CRLF sequences.
-     */
-    public function testDoubleCrlf()
+    public function testDoubleCrlf(): void
     {
         $test = "A\r\n\r\nB";
         $expected = "A\n\nB";
@@ -171,16 +154,13 @@ public function testDoubleCrlf()
         ftruncate($this->fp, 0);
         fwrite($this->fp, $test);
 
-        stream_filter_prepend($this->fp, 'horde_eol', STREAM_FILTER_READ, ['eol' => "\n"]);
+        stream_filter_prepend($this->fp, Eol::FILTER_NAME, STREAM_FILTER_READ, ['eol' => "\n"]);
         rewind($this->fp);
 
         $this->assertEquals($expected, stream_get_contents($this->fp));
     }
 
-    /**
-     * Test CR-only input conversion.
-     */
-    public function testCarriageReturnOnly()
+    public function testCarriageReturnOnly(): void
     {
         $test = "A\rB\rC";
         $expected = "A\nB\nC";
@@ -189,10 +169,9 @@ public function testCarriageReturnOnly()
         ftruncate($this->fp, 0);
         fwrite($this->fp, $test);
 
-        stream_filter_prepend($this->fp, 'horde_eol', STREAM_FILTER_READ, ['eol' => "\n"]);
+        stream_filter_prepend($this->fp, Eol::FILTER_NAME, STREAM_FILTER_READ, ['eol' => "\n"]);
         rewind($this->fp);
 
         $this->assertEquals($expected, stream_get_contents($this->fp));
     }
-
 }
diff --git a/test/Horde/Stream/Filter/NullFilterTest.php b/test/Horde/Stream/Filter/NullFilterTest.php
new file mode 100644
index 0000000..b91e519
--- /dev/null
+++ b/test/Horde/Stream/Filter/NullFilterTest.php
@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Horde\Stream\Filter;
+
+use Horde_Stream_Filter_Null;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+
+#[CoversClass(NullFilter::class)]
+class NullFilterTest extends TestCase
+{
+    private string $testdata;
+
+    /** @var resource */
+    private $fp;
+
+    public function setUp(): void
+    {
+        $this->testdata = "abcde\0fghij";
+        $this->fp = fopen('php://temp', 'r+');
+        fwrite($this->fp, $this->testdata);
+    }
+
+    public function tearDown(): void
+    {
+        fclose($this->fp);
+    }
+
+    public function testLegacyNull(): void
+    {
+        @stream_filter_register('horde_null', Horde_Stream_Filter_Null::class);
+        $filter = stream_filter_prepend($this->fp, 'horde_null', STREAM_FILTER_READ);
+        rewind($this->fp);
+
+        $this->assertEquals('abcdefghij', stream_get_contents($this->fp));
+
+        stream_filter_remove($filter);
+    }
+
+    public function testModernNullFilter(): void
+    {
+        NullFilter::register();
+        $filter = stream_filter_prepend($this->fp, NullFilter::FILTER_NAME, STREAM_FILTER_READ);
+        rewind($this->fp);
+
+        $this->assertEquals('abcdefghij', stream_get_contents($this->fp));
+
+        stream_filter_remove($filter);
+    }
+}
diff --git a/test/Horde/Stream/Filter/NullTest.php b/test/Horde/Stream/Filter/NullTest.php
deleted file mode 100644
index 2d74c2a..0000000
--- a/test/Horde/Stream/Filter/NullTest.php
+++ /dev/null
@@ -1,43 +0,0 @@
-<?php
-
-/**
- * @category   Horde
- * @package    Stream_Filter
- * @subpackage UnitTests
- */
-
-namespace Horde\Stream\Filter;
-
-use Horde_Test_Case as TestCase;
-
-/**
- * @category   Horde
- * @package    Stream_Filter
- * @subpackage UnitTests
- * @coversNothing
- */
-class NullTest extends TestCase
-{
-    public $fp;
-    public $testdata;
-
-    public function setup(): void
-    {
-        stream_filter_register('horde_null', 'Horde_Stream_Filter_Null');
-
-        $this->testdata = "abcde\0fghij";
-        $this->fp = fopen('php://temp', 'r+');
-        fwrite($this->fp, $this->testdata);
-    }
-
-    public function testNull()
-    {
-        $filter = stream_filter_prepend($this->fp, 'horde_null', STREAM_FILTER_READ);
-        rewind($this->fp);
-        $this->assertEquals(
-            'abcdefghij',
-            stream_get_contents($this->fp)
-        );
-        stream_filter_remove($filter);
-    }
-}
diff --git a/test/Horde/Stream/Filter/bootstrap.php b/test/Horde/Stream/Filter/bootstrap.php
deleted file mode 100644
index 95ebeca..0000000
--- a/test/Horde/Stream/Filter/bootstrap.php
+++ /dev/null
@@ -1,10 +0,0 @@
-<?php
-
-$autoload = __DIR__ . '/../../../../vendor/autoload.php';
-if (file_exists($autoload)) {
-    require_once $autoload;
-}
-if (!class_exists('Horde_Test_Bootstrap')) {
-    require_once 'Horde/Test/Bootstrap.php';
-}
-Horde_Test_Bootstrap::bootstrap(dirname(__FILE__));