diff --git a/src/ApiTestCase.php b/src/ApiTestCase.php
index 0410334..ea3d24d 100644
--- a/src/ApiTestCase.php
+++ b/src/ApiTestCase.php
@@ -13,6 +13,7 @@
 
 namespace ApiTestCase;
 
+use ApiTestCase\Renderer\ContextualDiffRenderer;
 use Coduo\PHPMatcher\Factory\MatcherFactory;
 use Coduo\PHPMatcher\Matcher;
 use Doctrine\Common\DataFixtures\Purger\ORMPurger;
@@ -169,8 +170,9 @@ protected function assertHeader(Response $response, string $contentType): void
     protected function assertResponseContent(string $actualResponse, string $filename, string $mimeType): void
     {
         $responseSource = $this->getExpectedResponsesFolder();
+        $expectedFilePath = PathBuilder::build($responseSource, sprintf('%s.%s', $filename, $mimeType));
 
-        $contents = file_get_contents(PathBuilder::build($responseSource, sprintf('%s.%s', $filename, $mimeType)));
+        $contents = file_get_contents($expectedFilePath);
         Assert::string($contents);
 
         $expectedResponse = trim($contents);
@@ -180,9 +182,18 @@ protected function assertResponseContent(string $actualResponse, string $filenam
         $result = $matcher->match($actualResponse, $expectedResponse);
 
         if (!$result) {
-            $diff = new \Diff(explode(\PHP_EOL, $expectedResponse), explode(\PHP_EOL, $actualResponse), []);
-
-            self::fail($matcher->getError() . \PHP_EOL . $diff->render(new \Diff_Renderer_Text_Unified()));
+            $diff = new \Diff(
+                explode(\PHP_EOL, $expectedResponse),
+                explode(\PHP_EOL, $actualResponse),
+                ['context' => 3]
+            );
+
+            $renderer = new ContextualDiffRenderer([
+                'expectedFilePath' => $expectedFilePath,
+                'matcher' => $matcher,
+            ]);
+
+            self::fail($diff->render($renderer));
         }
     }
 
diff --git a/src/Renderer/ContextualDiffRenderer.php b/src/Renderer/ContextualDiffRenderer.php
new file mode 100644
index 0000000..ef8b3aa
--- /dev/null
+++ b/src/Renderer/ContextualDiffRenderer.php
@@ -0,0 +1,209 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the ApiTestCase package.
+ *
+ * (c) Łukasz Chruściel
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace ApiTestCase\Renderer;
+
+use Coduo\PHPMatcher\Matcher;
+
+/**
+ * PHPUnit-like contextual diff renderer.
+ * Shows only differences with configurable context lines above and below each change.
+ * Marks missing expected values in red and unexpected actual values in green.
+ */
+class ContextualDiffRenderer extends \Diff_Renderer_Abstract
+{
+    /**
+     * @var \Diff
+     */
+    public $diff;
+
+    /**
+     * @var string|null Path to the expected response file for display
+     */
+    private ?string $expectedFilePath;
+
+    /**
+     * @var Matcher|null PHPMatcher instance for pattern-aware diffing
+     */
+    private ?Matcher $matcher;
+
+    /**
+     * @param array<string, mixed> $options Optional configuration:
+     *                                      - 'expectedFilePath' (string): Path to expected response file
+     *                                      - 'matcher' (Matcher): PHPMatcher for pattern-aware diffing
+     */
+    public function __construct(array $options = [])
+    {
+        parent::__construct($options);
+        $this->expectedFilePath = $options['expectedFilePath'] ?? null;
+        $this->matcher = $options['matcher'] ?? null;
+    }
+
+    /**
+     * Render and return a contextual diff with color highlighting.
+     *
+     * @return string The contextual diff output
+     */
+    public function render(): string
+    {
+        $output = '';
+
+        $opCodes = $this->diff->getGroupedOpcodes();
+
+        foreach ($opCodes as $group) {
+            $lastItem = count($group) - 1;
+            $i1 = $group[0][1];
+            $i2 = $group[$lastItem][2];
+            $j1 = $group[0][3];
+            $j2 = $group[$lastItem][4];
+
+            if ($i1 == 0 && $i2 == 0) {
+                $i1 = -1;
+                $i2 = -1;
+            }
+
+            $output .= sprintf("@@ -%d,%d +%d,%d @@\n", $i1 + 1, $i2 - $i1, $j1 + 1, $j2 - $j1);
+
+            foreach ($group as $code) {
+                [$tag, $i1, $i2, $j1, $j2] = $code;
+
+                if ($tag === 'equal') {
+                    // Context lines (unchanged)
+                    $lines = $this->diff->GetA($i1, $i2);
+                    foreach ($lines as $line) {
+                        $output .= ' ' . $line . "\n";
+                    }
+                } elseif ($tag === 'replace' && $this->matcher !== null) {
+                    $expectedLines = $this->diff->GetA($i1, $i2);
+                    $actualLines = $this->diff->GetB($j1, $j2);
+                    $maxLines = max(count($expectedLines), count($actualLines));
+
+                    for ($lineIndex = 0; $lineIndex < $maxLines; $lineIndex++) {
+                        $expectedLine = $expectedLines[$lineIndex] ?? '';
+                        $actualLine = $actualLines[$lineIndex] ?? '';
+
+                        if ($this->linesMatchViaPattern($actualLine, $expectedLine)) {
+                            $output .= ' ' . $actualLine . "\n";
+                        } else {
+                            if (isset($expectedLines[$lineIndex])) {
+                                $output .= $this->colorRed('-' . $expectedLine) . "\n";
+                            }
+                            if (isset($actualLines[$lineIndex])) {
+                                $output .= $this->colorGreen('+' . $actualLine) . "\n";
+                            }
+                        }
+                    }
+                } else {
+                    // Handle deletions (expected but not found in actual)
+                    if ($tag === 'replace' || $tag === 'delete') {
+                        $lines = $this->diff->GetA($i1, $i2);
+                        foreach ($lines as $line) {
+                            $output .= $this->colorRed('-' . $line) . "\n";
+                        }
+                    }
+
+                    // Handle insertions (unexpected in actual)
+                    if ($tag === 'replace' || $tag === 'insert') {
+                        $lines = $this->diff->GetB($j1, $j2);
+                        foreach ($lines as $line) {
+                            $output .= $this->colorGreen('+' . $line) . "\n";
+                        }
+                    }
+                }
+            }
+        }
+
+        // Add expected file path at the end if provided
+        if ($this->expectedFilePath !== null) {
+            $absolutePath = realpath($this->expectedFilePath) ?: $this->expectedFilePath;
+            $output .= sprintf("\nExpected file: %s\n", $absolutePath);
+        }
+
+        return $output;
+    }
+
+    /**
+     * Check if actual line matches expected line via phpmatcher patterns.
+     *
+     * @param string $actualLine The actual line from response
+     * @param string $expectedLine The expected line (may contain patterns)
+     * @return bool True if lines match via patterns
+     */
+    private function linesMatchViaPattern(string $actualLine, string $expectedLine): bool
+    {
+        if ($this->matcher === null) {
+            return false;
+        }
+
+        $result = $this->matcher->match($actualLine, $expectedLine);
+
+        return $result;
+    }
+
+    /**
+     * Apply red ANSI color code to a string (for expected but missing values).
+     *
+     * @param string $text Text to colorize
+     * @return string Colorized text
+     */
+    private function colorRed(string $text): string
+    {
+        if ($this->isColorSupported()) {
+            return "\033[31m" . $text . "\033[0m";
+        }
+
+        return $text;
+    }
+
+    /**
+     * Apply green ANSI color code to a string (for unexpected actual values).
+     *
+     * @param string $text Text to colorize
+     * @return string Colorized text
+     */
+    private function colorGreen(string $text): string
+    {
+        if ($this->isColorSupported()) {
+            return "\033[32m" . $text . "\033[0m";
+        }
+
+        return $text;
+    }
+
+    /**
+     * Check if ANSI color codes are supported in the current environment.
+     *
+     * @return bool True if colors are supported
+     */
+    private function isColorSupported(): bool
+    {
+        // Check if explicitly disabled
+        if (isset($_SERVER['NO_COLOR']) || getenv('NO_COLOR') !== false) {
+            return false;
+        }
+
+        // Check if output is to a terminal
+        if (function_exists('posix_isatty') && defined('STDOUT')) {
+            return @posix_isatty(STDOUT);
+        }
+
+        // For Windows, check for ANSICON or ConEmu or Windows 10+
+        if (DIRECTORY_SEPARATOR === '\\') {
+            return (getenv('ANSICON') !== false || getenv('ConEmuANSI') === 'ON' ||
+                    (function_exists('sapi_windows_vt100_support') && @sapi_windows_vt100_support(STDOUT)));
+        }
+
+        // Default to true for Unix-like systems
+        return true;
+    }
+}
diff --git a/test/src/Tests/Controller/SampleControllerJsonTest.php b/test/src/Tests/Controller/SampleControllerJsonTest.php
index 77de954..549e36e 100644
--- a/test/src/Tests/Controller/SampleControllerJsonTest.php
+++ b/test/src/Tests/Controller/SampleControllerJsonTest.php
@@ -157,4 +157,22 @@ public function testProductCreateResponse(): void
 
         $this->assertResponse($response, 'create_product', Response::HTTP_CREATED);
     }
+
+    public function testDiffVisualizationShowsContextAndColors(): void
+    {
+        try {
+            $this->client->request('GET', '/');
+            $response = $this->client->getResponse();
+            $this->assertResponse($response, 'incorrect_hello_world');
+            $this->fail('Expected assertion to fail but it passed');
+        } catch (AssertionFailedError $e) {
+            $message = $e->getMessage();
+
+            $this->assertStringContainsString('Expected file:', $message);
+            $this->assertStringContainsString('incorrect_hello_world.json', $message);
+            $this->assertStringContainsString('-', $message);
+            $this->assertStringContainsString('+', $message);
+            $this->assertStringContainsString('message', $message);
+        }
+    }
 }
diff --git a/test/src/Tests/Controller/SampleControllerXmlTest.php b/test/src/Tests/Controller/SampleControllerXmlTest.php
index 4abd230..a03ed56 100644
--- a/test/src/Tests/Controller/SampleControllerXmlTest.php
+++ b/test/src/Tests/Controller/SampleControllerXmlTest.php
@@ -91,4 +91,21 @@ public function testProductShowResponse(): void
 
         $this->assertResponse($response, 'get_product');
     }
+
+    public function testDiffVisualizationShowsContextAndColors(): void
+    {
+        try {
+            $this->client->request('GET', '/');
+            $response = $this->client->getResponse();
+            $this->assertResponse($response, 'incorrect_hello_world');
+            $this->fail('Expected assertion to fail but it passed');
+        } catch (AssertionFailedError $e) {
+            $message = $e->getMessage();
+
+            $this->assertStringContainsString('Expected file:', $message);
+            $this->assertStringContainsString('incorrect_hello_world.xml', $message);
+            $this->assertStringContainsString('-', $message);
+            $this->assertStringContainsString('+', $message);
+        }
+    }
 }
diff --git a/test/src/Tests/Renderer/ContextualDiffRendererTest.php b/test/src/Tests/Renderer/ContextualDiffRendererTest.php
new file mode 100644
index 0000000..2c73d2c
--- /dev/null
+++ b/test/src/Tests/Renderer/ContextualDiffRendererTest.php
@@ -0,0 +1,245 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the ApiTestCase package.
+ *
+ * (c) Łukasz Chruściel
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace ApiTestCase\Test\Tests\Renderer;
+
+use ApiTestCase\Renderer\ContextualDiffRenderer;
+use Coduo\PHPMatcher\Backtrace\VoidBacktrace;
+use Coduo\PHPMatcher\Factory\MatcherFactory;
+use PHPUnit\Framework\TestCase;
+
+class ContextualDiffRendererTest extends TestCase
+{
+    public function testRenderShowsOnlyDifferencesWithContext(): void
+    {
+        $expected = [
+            'line 1',
+            'line 2',
+            'line 3',
+            'line 4',
+            'line 5 expected',
+            'line 6',
+            'line 7',
+            'line 8',
+            'line 9',
+        ];
+
+        $actual = [
+            'line 1',
+            'line 2',
+            'line 3',
+            'line 4',
+            'line 5 actual',
+            'line 6',
+            'line 7',
+            'line 8',
+            'line 9',
+        ];
+
+        $diff = new \Diff($expected, $actual);
+        $renderer = new ContextualDiffRenderer(['context' => 3]);
+        $output = $diff->render($renderer);
+
+        $this->assertStringContainsString('line 2', $output);
+        $this->assertStringContainsString('line 3', $output);
+        $this->assertStringContainsString('line 4', $output);
+        $this->assertStringContainsString('line 5 expected', $output);
+        $this->assertStringContainsString('line 5 actual', $output);
+        $this->assertStringContainsString('line 6', $output);
+        $this->assertStringContainsString('line 7', $output);
+        $this->assertStringContainsString('line 8', $output);
+    }
+
+    public function testRenderIncludesExpectedFilePath(): void
+    {
+        $expected = ['line 1', 'line 2'];
+        $actual = ['line 1', 'line 3'];
+
+        $diff = new \Diff($expected, $actual);
+        $renderer = new ContextualDiffRenderer([
+            'context' => 3,
+            'expectedFilePath' => '/path/to/expected.json',
+        ]);
+        $output = $diff->render($renderer);
+
+        $this->assertStringContainsString('Expected file: /path/to/expected.json', $output);
+    }
+
+    public function testRenderHandlesInsertions(): void
+    {
+        $expected = ['line 1', 'line 2'];
+        $actual = ['line 1', 'line 2', 'line 3'];
+
+        $diff = new \Diff($expected, $actual);
+        $renderer = new ContextualDiffRenderer(['context' => 1]);
+        $output = $diff->render($renderer);
+
+        $this->assertStringContainsString('+line 3', $output);
+    }
+
+    public function testRenderHandlesDeletions(): void
+    {
+        $expected = ['line 1', 'line 2', 'line 3'];
+        $actual = ['line 1', 'line 2'];
+
+        $diff = new \Diff($expected, $actual);
+        $renderer = new ContextualDiffRenderer(['context' => 1]);
+        $output = $diff->render($renderer);
+
+        $this->assertStringContainsString('-line 3', $output);
+    }
+
+    public function testRenderHandlesMultipleDifferences(): void
+    {
+        $expected = [
+            'line 1',
+            'line 2 expected',
+            'line 3',
+            'line 4',
+            'line 5',
+            'line 6 expected',
+            'line 7',
+        ];
+
+        $actual = [
+            'line 1',
+            'line 2 actual',
+            'line 3',
+            'line 4',
+            'line 5',
+            'line 6 actual',
+            'line 7',
+        ];
+
+        $diff = new \Diff($expected, $actual);
+        $renderer = new ContextualDiffRenderer(['context' => 1]);
+        $output = $diff->render($renderer);
+
+        $this->assertStringContainsString('line 2 expected', $output);
+        $this->assertStringContainsString('line 2 actual', $output);
+        $this->assertStringContainsString('line 6 expected', $output);
+        $this->assertStringContainsString('line 6 actual', $output);
+    }
+
+    public function testRenderWithJsonDifferences(): void
+    {
+        $expected = [
+            '{',
+            '    "name": "John Doe",',
+            '    "age": 30,',
+            '    "email": "john@example.com"',
+            '}',
+        ];
+
+        $actual = [
+            '{',
+            '    "name": "Jane Doe",',
+            '    "age": 30,',
+            '    "email": "jane@example.com"',
+            '}',
+        ];
+
+        $diff = new \Diff($expected, $actual);
+        $renderer = new ContextualDiffRenderer(['context' => 2]);
+        $output = $diff->render($renderer);
+
+        $this->assertStringContainsString('"name": "John Doe"', $output);
+        $this->assertStringContainsString('"name": "Jane Doe"', $output);
+        $this->assertStringContainsString('"email": "john@example.com"', $output);
+        $this->assertStringContainsString('"email": "jane@example.com"', $output);
+        $this->assertStringContainsString('"age": 30', $output);
+    }
+
+    public function testRenderWithNoChanges(): void
+    {
+        $lines = ['line 1', 'line 2', 'line 3'];
+
+        $diff = new \Diff($lines, $lines);
+        $renderer = new ContextualDiffRenderer(['context' => 3]);
+        $output = $diff->render($renderer);
+
+        $this->assertEmpty(trim($output));
+    }
+
+    public function testColorOutputCanBeDisabled(): void
+    {
+        $_SERVER['NO_COLOR'] = '1';
+
+        $expected = ['line 1'];
+        $actual = ['line 2'];
+
+        $diff = new \Diff($expected, $actual);
+        $renderer = new ContextualDiffRenderer(['context' => 1]);
+        $output = $diff->render($renderer);
+
+        $this->assertStringNotContainsString("\033[", $output);
+
+        unset($_SERVER['NO_COLOR']);
+    }
+
+    public function testDefaultContextIsThreeLines(): void
+    {
+        $expected = [];
+        $actual = [];
+
+        for ($i = 1; $i <= 20; $i++) {
+            $expected[] = "line $i";
+            $actual[] = "line $i";
+        }
+
+        $expected[9] = 'line 10 expected';
+        $actual[9] = 'line 10 actual';
+
+        $diff = new \Diff($expected, $actual);
+        $renderer = new ContextualDiffRenderer();
+        $output = $diff->render($renderer);
+
+        $this->assertStringContainsString('line 7', $output);
+        $this->assertStringContainsString('line 8', $output);
+        $this->assertStringContainsString('line 9', $output);
+        $this->assertStringContainsString('line 11', $output);
+        $this->assertStringContainsString('line 12', $output);
+        $this->assertStringContainsString('line 13', $output);
+    }
+
+    public function testPatternAwareDiffDoesNotShowMatchingPatterns(): void
+    {
+        $expected = [
+            '{',
+            '    "message": @string@,',
+            '    "path": @string@,',
+            '    "count": 42',
+            '}',
+        ];
+
+        $actual = [
+            '{',
+            '    "message": "Hello World",',
+            '    "path": "/p/a/t/h",',
+            '    "count": 99',
+            '}',
+        ];
+
+        $matcherFactory = new MatcherFactory();
+        $matcher = $matcherFactory->createMatcher(new VoidBacktrace());
+
+        $diff = new \Diff($expected, $actual);
+        $renderer = new ContextualDiffRenderer(['matcher' => $matcher]);
+        $output = $diff->render($renderer);
+
+        $this->assertStringNotContainsString('"message": @string@', $output);
+        $this->assertStringNotContainsString('"path": @string@', $output);
+        $this->assertStringContainsString('-    "count": 42', $output);
+        $this->assertStringContainsString('+    "count": 99', $output);
+    }
+}