Add phpunit configuration

.gitignore

@@ -5,3 +5,4 @@
 /.php-cs-fixer.php
 /composer.lock
 /phpstan.neon
+/phpunit.xml

composer.json

@@ -20,11 +20,13 @@
         "php": "^8.2"
     },
     "require-dev": {
+        "nexusphp/tachycardia": "^2.3",
         "phpstan/extension-installer": "^1.4",
         "phpstan/phpstan": "^1.11",
         "phpstan/phpstan-deprecation-rules": "^1.2",
         "phpstan/phpstan-phpunit": "^1.4",
-        "phpstan/phpstan-strict-rules": "^1.6"
+        "phpstan/phpstan-strict-rules": "^1.6",
+        "phpunit/phpunit": "^11.2"
     },
     "minimum-stability": "dev",
     "prefer-stable": true,

phpunit.xml.dist

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/11.2/phpunit.xsd"
+         bootstrap="vendor/autoload.php"
+         cacheDirectory="build/.phpunit.cache"
+         colors="true"
+         columns="max"
+         executionOrder="random"
+         requireCoverageMetadata="true"
+         beStrictAboutCoverageMetadata="true"
+         beStrictAboutChangesToGlobalState="true"
+         beStrictAboutOutputDuringTests="true"
+         failOnRisky="true"
+         failOnWarning="true">
+    <testsuites>
+        <testsuite name="Nexus Test Suite">
+            <directory suffix="Test.php">tests/</directory>
+        </testsuite>
+    </testsuites>
+
+    <source ignoreIndirectDeprecations="true" restrictNotices="true" restrictWarnings="true">
+        <include>
+            <directory>src/Nexus/</directory>
+        </include>
+    </source>
+
+    <php>
+        <ini name="date.timezone" value="UTC" />
+        <ini name="memory_limit" value="-1" />
+    </php>
+
+    <extensions>
+        <bootstrap class="Nexus\PHPUnit\Tachycardia\TachycardiaExtension">
+            <parameter name="precision" value="2" />
+        </bootstrap>
+    </extensions>
+</phpunit>