diff --git a/.ai/conventions.md b/.ai/conventions.md
new file mode 100644
index 0000000..f797d60
--- /dev/null
+++ b/.ai/conventions.md
@@ -0,0 +1,32 @@
+# Neuron Framework - Coding Conventions
+
+## Code Style
+- Tab indentation (not spaces)
+- Opening braces on same line for class declarations, new line for methods/control structures
+- Spaces before parentheses in function calls: `function_name ($arg)`
+- Spaces around operators and after commas
+- PHP closing tag `?>` used in source files
+- PSR-4 autoloading under `Neuron\` namespace mapped to `src/Neuron/`
+
+## Input Validation Pattern
+All user input goes through `Tools::checkInput()` for validation, then `Tools::getInput()` for retrieval:
+1. `checkInput($value, $type)` returns bool - validates format
+2. `getInput($data, $key, $type, $default)` returns validated+processed value or default
+
+Supported types: text, varchar, string, html, name, email, username, password, date, datetime, number, int, md5, base64, url, bool, raw
+
+## Database Queries
+- Use `Query` class for parameterized queries
+- Parameter types: `PARAM_STR`, `PARAM_NUMBER`, `PARAM_DATE`, `PARAM_POINT`
+- Supports named parameters (`:name`) and positional (`?`) placeholders
+
+## Testing
+- Tests extend `PHPUnit\Framework\TestCase`
+- Test namespace: `Neuron\Tests`
+- Database-dependent tests use `#[Group('database')]` attribute
+- Run: `vendor/bin/phpunit --exclude-group=database`
+
+## Collections
+- Base `Collection` class is observable (extends `Observable`)
+- Triggers events: 'add', 'set', 'unset'
+- Implements Iterator, ArrayAccess, Countable interfaces
diff --git a/.ai/project-summary.md b/.ai/project-summary.md
new file mode 100644
index 0000000..e4ded1e
--- /dev/null
+++ b/.ai/project-summary.md
@@ -0,0 +1,44 @@
+# Neuron Framework - Project Summary
+
+## Overview
+Neuron is a lightweight PHP framework by CatLab Interactive. It provides core utilities for web applications including input validation, database query building, collections, encryption, URL building, filtering, and localization.
+
+## Architecture
+
+### Core Components
+- **Application** (`src/Neuron/Application.php`) - Main application dispatcher, singleton pattern
+- **Config** (`src/Neuron/Config.php`) - Configuration loader with dot-notation access and environment overrides
+- **Router** (`src/Neuron/Router.php`) - URL routing
+- **URLBuilder** (`src/Neuron/URLBuilder.php`) - Static URL construction utilities
+
+### Input Handling
+- **Tools** (`src/Neuron/Core/Tools.php`) - Input validation (`checkInput`) and retrieval (`getInput`) for types: text, varchar, string, html, name, email, username, password, date, datetime, number, int, md5, base64, url, bool, raw
+
+### Database
+- **Query** (`src/Neuron/DB/Query.php`) - Parameterized SQL query builder with INSERT, UPDATE, DELETE, SELECT support
+- **Database** (`src/Neuron/DB/Database.php`) - Database interface
+- **MySQL** (`src/Neuron/DB/MySQL.php`) - MySQL implementation
+
+### Collections
+- **Collection** (`src/Neuron/Collections/Collection.php`) - Observable collection implementing Iterator, ArrayAccess, Countable
+- **ModelCollection** (`src/Neuron/Collections/ModelCollection.php`) - Model-specific collection with ID indexing
+- **ErrorCollection** (`src/Neuron/Collections/ErrorCollection.php`) - Error message collection
+
+### Security
+- **SimpleCrypt** (`src/Neuron/Encryption/SimpleCrypt.php`) - AES-256-CBC encryption/decryption
+- **TokenGenerator** (`src/Neuron/Tools/TokenGenerator.php`) - Random token generation
+
+### Filtering
+- **Filter Parser/Scanner** (`src/Neuron/Filter/`) - Expression-based filtering with context support
+
+## Testing
+- Tests are in `tests/` directory using PHPUnit 10/11
+- Bootstrap in `tests/bootstrap.php`
+- Database tests are grouped with `#[Group('database')]` and excluded from CI
+- Run tests: `vendor/bin/phpunit --exclude-group=database`
+
+## Build & Dependencies
+- PHP >= 8.1
+- Composer for dependency management
+- Key dependencies: `nesbot/carbon`, `ext-gettext`
+- Dev dependency: `phpunit/phpunit`
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
new file mode 100644
index 0000000..989f50a
--- /dev/null
+++ b/.github/workflows/tests.yml
@@ -0,0 +1,36 @@
+name: Tests
+
+on:
+  push:
+    branches: [ master, main ]
+  pull_request:
+    branches: [ master, main ]
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        php-version: ['8.1', '8.2', '8.3']
+
+    name: PHP ${{ matrix.php-version }}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php-version }}
+          extensions: gettext, openssl, mbstring
+          coverage: xdebug
+
+      - name: Install dependencies
+        run: composer install --prefer-dist --no-progress
+
+      - name: Run tests
+        run: vendor/bin/phpunit --exclude-group=database
diff --git a/.gitignore b/.gitignore
index cdb3d20..9df1b6d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 .idea/
 vendor/
-composer.lock
\ No newline at end of file
+composer.lock
+.phpunit.cache
\ No newline at end of file
diff --git a/claude.md b/claude.md
new file mode 100644
index 0000000..ea6dd77
--- /dev/null
+++ b/claude.md
@@ -0,0 +1,43 @@
+# Claude AI Assistant Guide for Neuron Framework
+
+This document provides context for AI assistants working with the Neuron framework codebase.
+
+## Project Documentation
+
+- [Project Summary](.ai/project-summary.md) - Architecture overview and component descriptions
+- [Coding Conventions](.ai/conventions.md) - Code style, patterns, and testing practices
+
+## Quick Start
+
+### Install Dependencies
+```bash
+composer install
+```
+
+### Run Tests
+```bash
+# Run all tests (excluding database-dependent tests)
+vendor/bin/phpunit --exclude-group=database
+
+# Run specific test file
+vendor/bin/phpunit tests/ToolsTest.php
+
+# Run with coverage
+vendor/bin/phpunit --exclude-group=database --coverage-text
+```
+
+## Key Areas
+
+### Input Validation (`src/Neuron/Core/Tools.php`)
+The primary input validation layer. All user input should be validated through `Tools::checkInput()` before use. The `Tools::getInput()` method combines validation with data retrieval and type-specific processing.
+
+**Important**: Date validation uses `ctype_digit()` and `checkdate()` to ensure all date parts are valid integers representing a real date. The `getInput()` method casts date parts to `(int)` before passing to `mktime()` as a defence-in-depth measure.
+
+### Database Queries (`src/Neuron/DB/Query.php`)
+Always use parameterized queries via the `Query` class to prevent SQL injection. Never concatenate user input directly into SQL strings.
+
+### Testing
+Tests are located in `tests/` and use PHPUnit. Database-dependent tests are grouped with `#[Group('database')]` and require a MySQL connection. CI runs tests excluding this group.
+
+## CI/CD
+GitHub Actions workflow runs tests on PHP 8.1, 8.2, and 8.3. See `.github/workflows/tests.yml`.
diff --git a/composer.json b/composer.json
index 0afb7da..c2c4f85 100644
--- a/composer.json
+++ b/composer.json
@@ -15,18 +15,24 @@
     ],
 
     "require" : {
-        "php": ">=5.5.0",
+        "php": ">=8.1.0",
         "ext-gettext" : "*",
-        "nesbot/carbon": "~1.18"
+        "nesbot/carbon": "^2.0||^3.0"
     },
 
     "require-dev": {
-        "phpunit/phpunit": "5.1.*"
+        "phpunit/phpunit": "^10.0||^11.0"
     },
 
     "autoload": {
         "psr-4" : {
             "Neuron\\" : "src/Neuron/"
         }
+    },
+
+    "autoload-dev": {
+        "psr-4": {
+            "Neuron\\Tests\\" : "tests/"
+        }
     }
 }
diff --git a/phpunit.xml b/phpunit.xml
index 7362ee9..216c033 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -1,11 +1,13 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<phpunit bootstrap="tests/bootstrap.php">
+<phpunit bootstrap="tests/bootstrap.php"
+         colors="true"
+         cacheDirectory=".phpunit.cache">
 
-	<filter>
-		<whitelist>
+	<source>
+		<include>
 			<directory>src/Neuron</directory>
-		</whitelist>
-	</filter>
+		</include>
+	</source>
 
 	<testsuites>
 		<testsuite name="Neuron Test Suite">
diff --git a/src/Neuron/Core/Tools.php b/src/Neuron/Core/Tools.php
index 4c88481..740af75 100755
--- a/src/Neuron/Core/Tools.php
+++ b/src/Neuron/Core/Tools.php
@@ -34,7 +34,7 @@ public static function getInput ($dat, $key, $type, $default = null)
 					// For date's return timestamp.
 					case 'date':
 						$time = explode ('-', $dat[$key]);
-						return mktime (0, 0, 1, $time[1], $time[2], $time[0]);
+						return mktime (0, 0, 1, (int)$time[1], (int)$time[2], (int)$time[0]);
 
 					case 'datetime':
 						return new DateTime ($dat[$key]);
@@ -106,8 +106,15 @@ public static function checkInput ($value, $type)
 
 		elseif ($type == 'date')
 		{
-			$time = explode ('-', $value);
-			return self::isValidUTF8 ($value) && (count ($time) == 3);
+			if (!self::isValidUTF8($value)) {
+				return false;
+			}
+			$time = explode('-', $value);
+			return count($time) === 3
+				&& ctype_digit($time[0])
+				&& ctype_digit($time[1])
+				&& ctype_digit($time[2])
+				&& checkdate((int)$time[1], (int)$time[2], (int)$time[0]);
 		}
 
 		elseif ($type == 'datetime') {
diff --git a/src/Neuron/DB/Database.php b/src/Neuron/DB/Database.php
index 1b3a470..91d02dd 100755
--- a/src/Neuron/DB/Database.php
+++ b/src/Neuron/DB/Database.php
@@ -54,11 +54,26 @@ public function setLogger (Logger $logger)
 		$this->logger = $logger;
 	}
 
+	/** @var Database|null Test-only override, set via setInstance() */
+	private static $testInstance = null;
+
+	/**
+	 * Override the singleton instance for testing purposes.
+	 * @param Database|null $instance
+	 */
+	public static function setInstance (?Database $instance)
+	{
+		self::$testInstance = $instance;
+	}
+
 	/**
 	 * @return Database
 	 */
 	public static function getInstance ()
 	{
+		if (self::$testInstance !== null) {
+			return self::$testInstance;
+		}
 		return self::__getInstance ();
 	}
 
diff --git a/tests/CollectionTest.php b/tests/CollectionTest.php
new file mode 100644
index 0000000..b13d453
--- /dev/null
+++ b/tests/CollectionTest.php
@@ -0,0 +1,195 @@
+<?php
+
+namespace Neuron\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Neuron\Collections\Collection;
+
+class CollectionTest extends TestCase
+{
+	public function testAddAndCount ()
+	{
+		$collection = new Collection ();
+		$this->assertCount (0, $collection);
+
+		$collection->add ('a');
+		$collection->add ('b');
+		$collection->add ('c');
+		$this->assertCount (3, $collection);
+	}
+
+	public function testFirstAndLast ()
+	{
+		$collection = new Collection ();
+		$collection->add ('first');
+		$collection->add ('middle');
+		$collection->add ('last');
+
+		$this->assertEquals ('first', $collection->first ());
+		$this->assertEquals ('last', $collection->last ());
+	}
+
+	public function testFirstAndLastEmpty ()
+	{
+		$collection = new Collection ();
+		$this->assertNull ($collection->first ());
+		$this->assertNull ($collection->last ());
+	}
+
+	public function testIterator ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+		$collection->add ('b');
+		$collection->add ('c');
+
+		$values = [];
+		foreach ($collection as $key => $value) {
+			$values[$key] = $value;
+		}
+
+		$this->assertEquals ([0 => 'a', 1 => 'b', 2 => 'c'], $values);
+	}
+
+	public function testRewind ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+		$collection->add ('b');
+
+		// Iterate to end
+		foreach ($collection as $v) {}
+
+		// Rewind and verify
+		$collection->rewind ();
+		$this->assertEquals ('a', $collection->current ());
+	}
+
+	public function testArrayAccess ()
+	{
+		$collection = new Collection ();
+		$collection[] = 'value1';
+		$collection[] = 'value2';
+
+		$this->assertTrue (isset ($collection[0]));
+		$this->assertTrue (isset ($collection[1]));
+		$this->assertFalse (isset ($collection[2]));
+
+		$this->assertEquals ('value1', $collection[0]);
+		$this->assertEquals ('value2', $collection[1]);
+	}
+
+	public function testOffsetSet ()
+	{
+		$collection = new Collection ();
+		$collection[5] = 'value5';
+
+		$this->assertTrue (isset ($collection[5]));
+		$this->assertEquals ('value5', $collection[5]);
+	}
+
+	public function testOffsetUnset ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+		$collection->add ('b');
+
+		unset ($collection[0]);
+		$this->assertFalse (isset ($collection[0]));
+	}
+
+	public function testRemove ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+		$collection->add ('b');
+		$collection->add ('c');
+
+		$result = $collection->remove ('b');
+		$this->assertTrue ($result);
+		$this->assertCount (2, $collection);
+	}
+
+	public function testRemoveNonExistent ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+
+		$result = $collection->remove ('nonexistent');
+		$this->assertFalse ($result);
+	}
+
+	public function testClear ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+		$collection->add ('b');
+
+		$collection->clear ();
+		$this->assertCount (0, $collection);
+	}
+
+	public function testPeek ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+		$collection->add ('b');
+		$collection->add ('c');
+
+		$collection->rewind ();
+		$this->assertEquals ('a', $collection->current ());
+		$this->assertEquals ('b', $collection->peek ());
+		// Position should not have changed
+		$this->assertEquals ('a', $collection->current ());
+	}
+
+	public function testPeekAtEnd ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+
+		$collection->rewind ();
+		$this->assertNull ($collection->peek ());
+	}
+
+	public function testReverse ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+		$collection->add ('b');
+		$collection->add ('c');
+
+		$collection->reverse ();
+		$this->assertEquals ('c', $collection->first ());
+		$this->assertEquals ('a', $collection->last ());
+	}
+
+	public function testCurrentAtInvalidPosition ()
+	{
+		$collection = new Collection ();
+		$this->assertNull ($collection->current ());
+	}
+
+	public function testValid ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+
+		$collection->rewind ();
+		$this->assertTrue ($collection->valid ());
+		$collection->next ();
+		$this->assertFalse ($collection->valid ());
+	}
+
+	public function testKey ()
+	{
+		$collection = new Collection ();
+		$collection->add ('a');
+		$collection->add ('b');
+
+		$collection->rewind ();
+		$this->assertEquals (0, $collection->key ());
+		$collection->next ();
+		$this->assertEquals (1, $collection->key ());
+	}
+}
diff --git a/tests/DbQueryInjectionTest.php b/tests/DbQueryInjectionTest.php
new file mode 100644
index 0000000..a4a82a7
--- /dev/null
+++ b/tests/DbQueryInjectionTest.php
@@ -0,0 +1,862 @@
+<?php
+
+namespace Neuron\Tests;
+
+use DateTime;
+use Neuron\DB\Database;
+use Neuron\DB\Query;
+use Neuron\Exceptions\InvalidParameter;
+use Neuron\Models\Geo\Point;
+use PHPUnit\Framework\TestCase;
+
+/**
+ * Comprehensive tests for Neuron\DB\Query covering SQL injection defences,
+ * all parameter types, all query builders, and edge cases.
+ * Runs without a real MySQL connection by injecting a TestDatabase stub.
+ */
+class DbQueryInjectionTest extends TestCase
+{
+protected function setUp (): void
+{
+Database::setInstance (new TestDatabase ());
+}
+
+protected function tearDown (): void
+{
+Database::setInstance (null);
+}
+
+// ---------------------------------------------------------------
+// PARAM_STR — SQL injection through string parameters
+// ---------------------------------------------------------------
+
+public function testStringParamEscapesSingleQuote ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE name = ?");
+$query->bindValue (1, "O'Reilly", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+// Single quote must be escaped as \'
+$this->assertStringContainsString ("\\'", $sql);
+// The value is wrapped in outer single quotes
+$this->assertStringContainsString ("name = '", $sql);
+}
+
+public function testStringParamEscapesDoubleQuote ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE name = ?");
+$query->bindValue (1, 'Say "hello"', Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ('\\"', $sql);
+}
+
+public function testStringParamEscapesBackslash ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE path = ?");
+$query->bindValue (1, 'C:\\Users\\test', Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ('\\\\', $sql);
+}
+
+public function testStringParamEscapesNewline ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE note = ?");
+$query->bindValue (1, "line1\nline2", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ('\\n', $sql);
+}
+
+public function testStringParamEscapesNullByte ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE name = ?");
+$query->bindValue (1, "name\x00injected", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ('\\0', $sql);
+}
+
+public function testClassicOrInjectionInString ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE username = ?");
+$query->bindValue (1, "' OR '1'='1", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+// The dangerous ' is escaped to \' preventing context break-out
+$this->assertStringContainsString ("\\'", $sql);
+// Verify the whole value is inside outer quotes
+$this->assertStringContainsString ("username = '", $sql);
+}
+
+public function testDropTableInjectionInString ()
+{
+$query = new Query ("INSERT INTO `log` SET message = ?");
+$query->bindValue (1, "'; DROP TABLE users;--", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+// The leading ' is escaped so the payload cannot break out of the string context
+$this->assertStringContainsString ("\\'", $sql);
+$this->assertStringContainsString ("message = '", $sql);
+}
+
+public function testUnionSelectInjectionInString ()
+{
+$query = new Query ("SELECT * FROM `products` WHERE name = ?");
+$query->bindValue (1, "' UNION SELECT username, password FROM users--", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+// The single quote is escaped; the UNION cannot be executed as SQL
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+public function testSleepInjectionInString ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE id = ?");
+$query->bindValue (1, "1' AND SLEEP(5)--", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+// The single quote is escaped
+$this->assertStringContainsString ("\\'", $sql);
+$this->assertStringContainsString ("id = '", $sql);
+}
+
+public function testStackedQueryInjection ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE name = ?");
+$query->bindValue (1, "admin'; SELECT * FROM secrets;--", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+// Quote escaped; second statement cannot execute
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+public function testCommentBasedInjectionInString ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE name = ?");
+$query->bindValue (1, "admin'--", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+// Single quote must be escaped
+$this->assertStringContainsString ("admin\\'--", $sql);
+}
+
+public function testBlindInjectionInString ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE name = ?");
+$query->bindValue (1, "' AND 1=1--", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+// Single quote escaped
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+public function testNumericValueInStringParam ()
+{
+$query = new Query ("SELECT * FROM `t` WHERE col = ?");
+$query->bindValue (1, 42, Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("'42'", $sql);
+}
+
+public function testFloatValueInStringParam ()
+{
+$query = new Query ("SELECT * FROM `t` WHERE col = ?");
+$query->bindValue (1, 3.14, Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("'3.14'", $sql);
+}
+
+// ---------------------------------------------------------------
+// PARAM_UNKNOWN — automatic type detection
+// ---------------------------------------------------------------
+
+public function testUnknownParamIntIsNotQuoted ()
+{
+$query = new Query ("SELECT * FROM `t` WHERE id = ?");
+$query->bindValue (1, 5, Query::PARAM_UNKNOWN);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("id = 5", $sql);
+$this->assertStringNotContainsString ("id = '5'", $sql);
+}
+
+public function testUnknownParamStringInjection ()
+{
+$query = new Query ("SELECT * FROM `t` WHERE name = ?");
+$query->bindValue (1, "' OR '1'='1", Query::PARAM_UNKNOWN);
+$sql = $query->getParsedQuery ();
+
+// Single quote escaped
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+public function testUnknownParamCommaStringNotModified ()
+{
+// Comma-format "3,14" is not is_numeric(), treated as string
+$query = new Query ("SELECT * FROM `t` WHERE val = ?");
+$query->bindValue (1, "3,14", Query::PARAM_UNKNOWN);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("'3,14'", $sql);
+}
+
+// ---------------------------------------------------------------
+// PARAM_NUMBER — numeric parameter protection
+// ---------------------------------------------------------------
+
+public function testNumberParamValidInt ()
+{
+$query = new Query ("SELECT * FROM `t` WHERE id = ?");
+$query->bindValue (1, 42, Query::PARAM_NUMBER);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("id = 42", $sql);
+}
+
+public function testNumberParamValidFloat ()
+{
+$query = new Query ("SELECT * FROM `t` WHERE price = ?");
+$query->bindValue (1, 9.99, Query::PARAM_NUMBER);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("price = 9.99", $sql);
+}
+
+public function testNumberParamThrowsOnNonNumericString ()
+{
+$this->expectException (InvalidParameter::class);
+
+$query = new Query ("SELECT * FROM `t` WHERE id = ?");
+$query->bindValue (1, "'; DROP TABLE users;--", Query::PARAM_NUMBER);
+$query->getParsedQuery ();
+}
+
+public function testNumberParamThrowsOnInjectionString ()
+{
+$this->expectException (InvalidParameter::class);
+
+$query = new Query ("SELECT * FROM `t` WHERE id = ?");
+$query->bindValue (1, "1 OR 1=1", Query::PARAM_NUMBER);
+$query->getParsedQuery ();
+}
+
+public function testNumberParamThrowsOnUnionSelect ()
+{
+$this->expectException (InvalidParameter::class);
+
+$query = new Query ("SELECT * FROM `t` WHERE id = ?");
+$query->bindValue (1, "1 UNION SELECT password FROM users", Query::PARAM_NUMBER);
+$query->getParsedQuery ();
+}
+
+public function testNumberParamThrowsOnAlphaString ()
+{
+$this->expectException (InvalidParameter::class);
+
+$query = new Query ("SELECT * FROM `t` WHERE id = ?");
+$query->bindValue (1, "admin", Query::PARAM_NUMBER);
+$query->getParsedQuery ();
+}
+
+// ---------------------------------------------------------------
+// PARAM_DATE
+// ---------------------------------------------------------------
+
+public function testDateParamTimestamp ()
+{
+$ts = gmmktime (0, 0, 0, 6, 15, 2020);
+
+$query = new Query ("SELECT * FROM `t` WHERE created = ?");
+$query->bindValue (1, $ts, Query::PARAM_DATE);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("FROM_UNIXTIME($ts)", $sql);
+}
+
+public function testDateParamDateTimeObject ()
+{
+$dt = new DateTime ('2020-06-15 12:30:00');
+
+$query = new Query ("SELECT * FROM `t` WHERE created = ?");
+$query->bindValue (1, $dt, Query::PARAM_DATE);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("'2020-06-15 12:30:00'", $sql);
+}
+
+public function testDateParamThrowsOnInjectionString ()
+{
+$this->expectException (InvalidParameter::class);
+
+$query = new Query ("SELECT * FROM `t` WHERE created = ?");
+$query->bindValue (1, "' OR '1'='1", Query::PARAM_DATE);
+$query->getParsedQuery ();
+}
+
+public function testDateParamThrowsOnNonNumericString ()
+{
+$this->expectException (InvalidParameter::class);
+
+$query = new Query ("SELECT * FROM `t` WHERE created = ?");
+$query->bindValue (1, "not-a-date", Query::PARAM_DATE);
+$query->getParsedQuery ();
+}
+
+// ---------------------------------------------------------------
+// PARAM_POINT
+// ---------------------------------------------------------------
+
+public function testPointParam ()
+{
+$point = new Point (4.3517, 50.8503);
+
+$query = new Query ("INSERT INTO `locations` SET pos = ?");
+$query->bindValue (1, $point, Query::PARAM_POINT);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("POINT(4.3517,50.8503)", $sql);
+}
+
+public function testPointParamThrowsOnNonPoint ()
+{
+$this->expectException (InvalidParameter::class);
+
+$query = new Query ("INSERT INTO `locations` SET pos = ?");
+$query->bindValue (1, "POINT(0,0) INJECTION", Query::PARAM_POINT);
+$query->getParsedQuery ();
+}
+
+public function testPointConstructorRejectsNonNumeric ()
+{
+$this->expectException (InvalidParameter::class);
+new Point ("x", "y");
+}
+
+// ---------------------------------------------------------------
+// NULL handling
+// ---------------------------------------------------------------
+
+public function testNullValueWithCanBeNullTrue ()
+{
+// null value + canBeNull=true → should produce NULL in SQL
+$query = new Query ("UPDATE `t` SET col = ?");
+$query->bindValue (1, null, Query::PARAM_STR, true);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("col = NULL", $sql);
+}
+
+public function testNullValueWithCanBeNullFalse ()
+{
+// null value + canBeNull=false (default) → treated as empty string
+$query = new Query ("UPDATE `t` SET col = ?");
+$query->bindValue (1, null, Query::PARAM_STR, false);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("col = ''", $sql);
+}
+
+public function testNullInWhereProducesIsNull ()
+{
+$query = Query::select ('users', array ('id'), array ('deleted_at' => null));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("deleted_at IS NULL", $sql);
+}
+
+public function testNullViaStaticBuilderProducesNull ()
+{
+// Via static builder, no explicit type → $v[2] not set → defaults to true
+// in getParsedQuery → null produces NULL
+$query = Query::insert ('t', array ('col' => null));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("col = NULL", $sql);
+}
+
+// ---------------------------------------------------------------
+// Auto-detection of DateTime and Point (via bindValues without type)
+// ---------------------------------------------------------------
+
+public function testAutoDetectDateTimeViaBindValues ()
+{
+$dt = new DateTime ('2023-01-15 08:00:00');
+
+$query = new Query ("INSERT INTO `t` SET created = ?");
+$query->bindValues (array (array ($dt)));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("'2023-01-15 08:00:00'", $sql);
+}
+
+public function testAutoDetectPointViaBindValues ()
+{
+$point = new Point (10.5, 20.3);
+
+$query = new Query ("INSERT INTO `t` SET pos = ?");
+$query->bindValues (array (array ($point)));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("POINT(10.5,20.3)", $sql);
+}
+
+// ---------------------------------------------------------------
+// Array (IN clause) values
+// ---------------------------------------------------------------
+
+public function testArrayValueForInClause ()
+{
+$query = Query::select ('users', array ('id', 'name'), array (
+'id' => array (array (1, 2, 3), Query::PARAM_NUMBER),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("(1,2,3)", $sql);
+}
+
+public function testArrayStringValuesEscaped ()
+{
+$query = Query::select ('users', array ('name'), array (
+'name' => array (array ("admin", "' OR '1'='1"), Query::PARAM_STR),
+));
+$sql = $query->getParsedQuery ();
+
+// The dangerous single quote in the injection payload must be escaped
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+// ---------------------------------------------------------------
+// WHERE comparators
+// ---------------------------------------------------------------
+
+public function testWhereNotEqualsPrefix ()
+{
+$query = Query::select ('t', array (), array (
+'status' => array ('!active', Query::PARAM_STR),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("status != ", $sql);
+$this->assertStringContainsString ("'active'", $sql);
+}
+
+public function testWhereLike ()
+{
+$query = Query::select ('t', array (), array (
+'name' => array ('%test%', Query::PARAM_STR, 'LIKE'),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("name LIKE ", $sql);
+$this->assertStringContainsString ("'%test%'", $sql);
+}
+
+public function testWhereNot ()
+{
+$query = Query::select ('t', array (), array (
+'type' => array ('admin', Query::PARAM_STR, 'NOT'),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("type != ", $sql);
+}
+
+public function testWhereGreaterThan ()
+{
+$query = Query::select ('t', array (), array (
+'age' => array (18, Query::PARAM_NUMBER, '>'),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("age > ", $sql);
+$this->assertStringContainsString ("18", $sql);
+}
+
+public function testWhereLessThan ()
+{
+$query = Query::select ('t', array (), array (
+'age' => array (65, Query::PARAM_NUMBER, '<'),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("age < 65", $sql);
+}
+
+public function testWhereGreaterOrEqual ()
+{
+$query = Query::select ('t', array (), array (
+'score' => array (100, Query::PARAM_NUMBER, '>='),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("score >= 100", $sql);
+}
+
+public function testWhereLessOrEqual ()
+{
+$query = Query::select ('t', array (), array (
+'score' => array (50, Query::PARAM_NUMBER, '<='),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("score <= 50", $sql);
+}
+
+public function testWhereNotEqualsOperator ()
+{
+$query = Query::select ('t', array (), array (
+'status' => array (0, Query::PARAM_NUMBER, '!='),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("status != 0", $sql);
+}
+
+public function testWhereInOperator ()
+{
+$query = Query::select ('t', array (), array (
+'id' => array (array (1, 2, 3), Query::PARAM_NUMBER, 'IN'),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("id IN ", $sql);
+$this->assertStringContainsString ("(1,2,3)", $sql);
+}
+
+public function testWhereArrayImplicitIn ()
+{
+$query = Query::select ('t', array (), array (
+'id' => array (array (5, 10, 15), Query::PARAM_NUMBER),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("id IN ", $sql);
+}
+
+// ---------------------------------------------------------------
+// SELECT builder
+// ---------------------------------------------------------------
+
+public function testSelectAllColumns ()
+{
+$query = Query::select ('users', array (), array ('active' => array (1, Query::PARAM_NUMBER)));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringStartsWith ("SELECT *", $sql);
+$this->assertStringContainsString ("FROM `users`", $sql);
+$this->assertStringContainsString ("WHERE active = 1", $sql);
+}
+
+public function testSelectSpecificColumns ()
+{
+$query = Query::select ('users', array ('id', 'email'), array ());
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("SELECT id, email", $sql);
+$this->assertStringContainsString ("FROM `users`", $sql);
+}
+
+public function testSelectNoWhere ()
+{
+$query = Query::select ('users', array ('id'));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringNotContainsString ("WHERE", $sql);
+}
+
+public function testSelectWithOrder ()
+{
+$query = Query::select ('users', array ('id'), array (), array ('name ASC', 'created DESC'));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("ORDER BY name ASC, created DESC", $sql);
+}
+
+public function testSelectWithLimit ()
+{
+$query = Query::select ('users', array ('id'), array (), array (), '10, 20');
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("LIMIT 10, 20", $sql);
+}
+
+public function testSelectWithOrderAndLimit ()
+{
+$query = Query::select ('users', array ('id'), array (), array ('id ASC'), '0, 5');
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("ORDER BY id ASC", $sql);
+$this->assertStringContainsString ("LIMIT 0, 5", $sql);
+}
+
+// ---------------------------------------------------------------
+// INSERT builder
+// ---------------------------------------------------------------
+
+public function testInsertBasic ()
+{
+$query = Query::insert ('users', array (
+'name' => 'Alice',
+'age'  => array (30, Query::PARAM_NUMBER),
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringStartsWith ("INSERT INTO `users`", $sql);
+$this->assertStringContainsString ("name = 'Alice'", $sql);
+$this->assertStringContainsString ("age = 30", $sql);
+}
+
+public function testInsertEscapesSingleQuote ()
+{
+$query = Query::insert ('users', array ('name' => "O'Brien"));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+public function testInsertWithInjectionPayload ()
+{
+$query = Query::insert ('log', array ('msg' => "'; DROP TABLE users;--"));
+$sql = $query->getParsedQuery ();
+
+// Single quote is escaped — the payload cannot break out of the string context
+$this->assertStringContainsString ("\\'", $sql);
+$this->assertStringContainsString ("msg = '", $sql);
+}
+
+public function testInsertWithNullValue ()
+{
+$query = Query::insert ('users', array ('id' => 1, 'bio' => null));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("bio = NULL", $sql);
+}
+
+// ---------------------------------------------------------------
+// REPLACE builder
+// ---------------------------------------------------------------
+
+public function testReplaceBasic ()
+{
+$query = Query::replace ('users', array (
+'id'   => array (1, Query::PARAM_NUMBER),
+'name' => 'Bob',
+));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringStartsWith ("REPLACE INTO `users`", $sql);
+$this->assertStringContainsString ("id = 1", $sql);
+$this->assertStringContainsString ("name = 'Bob'", $sql);
+}
+
+public function testReplaceWithInjectionPayload ()
+{
+$query = Query::replace ('users', array ('name' => "'; DROP TABLE users;--"));
+$sql = $query->getParsedQuery ();
+
+// Single quote is escaped
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+// ---------------------------------------------------------------
+// UPDATE builder
+// ---------------------------------------------------------------
+
+public function testUpdateBasic ()
+{
+$query = Query::update (
+'users',
+array ('name' => 'Alice'),
+array ('id'   => array (1, Query::PARAM_NUMBER))
+);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringStartsWith ("UPDATE `users`", $sql);
+$this->assertStringContainsString ("SET name = 'Alice'", $sql);
+$this->assertStringContainsString ("WHERE id = 1", $sql);
+}
+
+public function testUpdateWithInjectionInSet ()
+{
+$query = Query::update (
+'users',
+array ('bio' => "'; DROP TABLE secrets;--"),
+array ('id'  => array (42, Query::PARAM_NUMBER))
+);
+$sql = $query->getParsedQuery ();
+
+// Single quote escaped in the SET clause
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+public function testUpdateWithInjectionInWhere ()
+{
+$query = Query::update (
+'users',
+array ('bio' => 'safe value'),
+array ('name' => "' OR '1'='1")
+);
+$sql = $query->getParsedQuery ();
+
+// Single quote in WHERE value must be escaped
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+// ---------------------------------------------------------------
+// DELETE builder
+// ---------------------------------------------------------------
+
+public function testDeleteBasic ()
+{
+$query = Query::delete ('users', array ('id' => array (5, Query::PARAM_NUMBER)));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringStartsWith ("DELETE FROM `users`", $sql);
+$this->assertStringContainsString ("WHERE id = 5", $sql);
+}
+
+public function testDeleteWithInjectionInWhere ()
+{
+$query = Query::delete ('users', array ('name' => "' OR '1'='1"));
+$sql = $query->getParsedQuery ();
+
+// Single quote escaped
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+public function testDeleteNoWhere ()
+{
+$query = Query::delete ('t', array ());
+$sql = $query->getParsedQuery ();
+
+$this->assertStringStartsWith ("DELETE FROM `t`", $sql);
+$this->assertStringNotContainsString ("WHERE", $sql);
+}
+
+// ---------------------------------------------------------------
+// Named parameters injection
+// ---------------------------------------------------------------
+
+public function testNamedParamInjection ()
+{
+$query = new Query ("SELECT * FROM `users` WHERE name = :name AND role = :role");
+$query->bindValue ('name', "' OR '1'='1");
+$query->bindValue ('role', 'admin');
+$sql = $query->getParsedQuery ();
+
+// Single quote in named param must be escaped
+$this->assertStringContainsString ("\\'", $sql);
+$this->assertStringContainsString ("role = 'admin'", $sql);
+}
+
+public function testNamedParamDoesNotReplaceItselfInValue ()
+{
+$query = new Query ("INSERT INTO `t` SET a = :a, b = :b");
+$query->bindValue ('a', 'value with :b placeholder');
+$query->bindValue ('b', 'real b');
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("a = 'value with :b placeholder'", $sql);
+$this->assertStringContainsString ("b = 'real b'", $sql);
+}
+
+// ---------------------------------------------------------------
+// Positional parameters with injection
+// ---------------------------------------------------------------
+
+public function testPositionalParamsWithInjection ()
+{
+$query = new Query ("SELECT * FROM `t` WHERE a = ? AND b = ?");
+$query->bindValue (1, "' OR 1=1--");
+$query->bindValue (2, "'; DROP TABLE t;--");
+$sql = $query->getParsedQuery ();
+
+// Both single quotes must be escaped
+$this->assertStringContainsString ("\\'", $sql);
+}
+
+public function testQuestionMarkInValueDoesNotBreakParsing ()
+{
+$query = new Query ("INSERT INTO `t` SET msg = ?, other = ?");
+$query->bindValue (1, "Is this a question?");
+$query->bindValue (2, "yes");
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("msg = 'Is this a question?'", $sql);
+$this->assertStringContainsString ("other = 'yes'", $sql);
+}
+
+// ---------------------------------------------------------------
+// bindValue chaining
+// ---------------------------------------------------------------
+
+public function testBindValueChaining ()
+{
+$query = (new Query ("SELECT * FROM `t` WHERE a = ? AND b = ?"))
+->bindValue (1, 'foo')
+->bindValue (2, 'bar');
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ("a = 'foo'", $sql);
+$this->assertStringContainsString ("b = 'bar'", $sql);
+}
+
+// ---------------------------------------------------------------
+// Table name escaping
+// ---------------------------------------------------------------
+
+public function testTableNameIsBacktickEscaped ()
+{
+$query = Query::select ('my_table', array ('id'));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ('`my_table`', $sql);
+}
+
+public function testInsertTableNameIsBacktickEscaped ()
+{
+$query = Query::insert ('log_entries', array ('msg' => 'test'));
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ('`log_entries`', $sql);
+}
+
+// ---------------------------------------------------------------
+// Edge cases with special characters
+// ---------------------------------------------------------------
+
+public function testCarriageReturnEscaped ()
+{
+$query = new Query ("INSERT INTO `t` SET data = ?");
+$query->bindValue (1, "line1\rline2", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ('\\r', $sql);
+}
+
+public function testSubstituteCharacterEscaped ()
+{
+$query = new Query ("INSERT INTO `t` SET data = ?");
+$query->bindValue (1, "data\x1amore", Query::PARAM_STR);
+$sql = $query->getParsedQuery ();
+
+$this->assertStringContainsString ('\\Z', $sql);
+}
+
+public function testMultipleInjectionVectorsInSingleQuery ()
+{
+$query = Query::insert ('audit_log', array (
+'user'    => "' OR '1'='1",
+'action'  => "'; DROP TABLE audit_log;--",
+'payload' => "' UNION SELECT password FROM users--",
+));
+$sql = $query->getParsedQuery ();
+
+// All dangerous single quotes must be escaped
+$this->assertGreaterThanOrEqual (3, substr_count ($sql, "\\'"));
+}
+}
diff --git a/tests/DbQueryTest.php b/tests/DbQueryTest.php
index f145e6c..8a924ae 100644
--- a/tests/DbQueryTest.php
+++ b/tests/DbQueryTest.php
@@ -2,14 +2,16 @@
 
 namespace Neuron\Tests;
 
-use PHPUnit_Framework_TestCase;
+use PHPUnit\Framework\TestCase;
+use PHPUnit\Framework\Attributes\Group;
 use Neuron\DB\Query;
 
 /**
  * Class DbQueryTest
  * @package Neuron\Tests
  */
-class DbQueryTest extends PHPUnit_Framework_TestCase
+#[Group('database')]
+class DbQueryTest extends TestCase
 {
     /**
      * @test
diff --git a/tests/ErrorCollectionTest.php b/tests/ErrorCollectionTest.php
new file mode 100644
index 0000000..5b8786e
--- /dev/null
+++ b/tests/ErrorCollectionTest.php
@@ -0,0 +1,55 @@
+<?php
+
+namespace Neuron\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Neuron\Collections\ErrorCollection;
+
+class ErrorCollectionTest extends TestCase
+{
+	public function testAddError ()
+	{
+		$collection = new ErrorCollection ();
+		$error = $collection->addError ('Something went wrong');
+
+		$this->assertCount (1, $collection);
+		$this->assertInstanceOf (\Neuron\Models\Error::class, $error);
+	}
+
+	public function testGetData ()
+	{
+		$collection = new ErrorCollection ();
+		$collection->addError ('Error %s', ['one']);
+		$collection->addError ('Error %s', ['two']);
+
+		$data = $collection->getData ();
+		$this->assertCount (2, $data);
+		$this->assertEquals ('Error one', $data[0]);
+		$this->assertEquals ('Error two', $data[1]);
+	}
+
+	public function testGetDetailedData ()
+	{
+		$collection = new ErrorCollection ();
+		$error = $collection->addError ('Error %s in %s', ['field', 'form']);
+		$error->setSubject ('test_subject');
+		$error->setCode ('ERR001');
+
+		$detailed = $collection->getDetailedData ();
+		$this->assertCount (1, $detailed);
+		$this->assertEquals ('Error field in form', $detailed[0]['message']);
+		$this->assertEquals ('Error %s in %s', $detailed[0]['template']);
+		$this->assertEquals (['field', 'form'], $detailed[0]['arguments']);
+		$this->assertEquals ('test_subject', $detailed[0]['subject']);
+		$this->assertEquals ('ERR001', $detailed[0]['code']);
+	}
+
+	public function testAddErrorWithNoArguments ()
+	{
+		$collection = new ErrorCollection ();
+		$collection->addError ('Simple error message');
+
+		$data = $collection->getData ();
+		$this->assertEquals ('Simple error message', $data[0]);
+	}
+}
diff --git a/tests/FilterTest.php b/tests/FilterTest.php
index e79f8f6..6fd1993 100644
--- a/tests/FilterTest.php
+++ b/tests/FilterTest.php
@@ -10,13 +10,13 @@
 
 use Neuron\Filter\Context;
 use Neuron\Filter\Field;
-use PHPUnit_Framework_TestCase;
+use PHPUnit\Framework\TestCase;
 
 use Neuron\Filter\Parser;
 use Neuron\Filter\Scanner;
 
 class FilterTest
-	extends PHPUnit_Framework_TestCase
+	extends TestCase
 {
 
 	public function testFilter ()
diff --git a/tests/SimpleCryptTest.php b/tests/SimpleCryptTest.php
new file mode 100644
index 0000000..34851bc
--- /dev/null
+++ b/tests/SimpleCryptTest.php
@@ -0,0 +1,81 @@
+<?php
+
+namespace Neuron\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Neuron\Encryption\SimpleCrypt;
+
+class SimpleCryptTest extends TestCase
+{
+	public function testEncryptDecrypt ()
+	{
+		$crypt = new SimpleCrypt ('test_password');
+		$original = 'Hello World!';
+
+		$encrypted = $crypt->encrypt ($original);
+		$this->assertNotEquals ($original, $encrypted);
+
+		$decrypted = $crypt->decrypt ($encrypted);
+		$this->assertEquals ($original, $decrypted);
+	}
+
+	public function testDifferentPasswordsFail ()
+	{
+		$crypt1 = new SimpleCrypt ('password1');
+		$crypt2 = new SimpleCrypt ('password2');
+
+		$encrypted = $crypt1->encrypt ('secret');
+		$decrypted = $crypt2->decrypt ($encrypted);
+
+		$this->assertNotEquals ('secret', $decrypted);
+	}
+
+	public function testEncryptProducesDifferentOutput ()
+	{
+		$crypt = new SimpleCrypt ('password');
+
+		$encrypted1 = $crypt->encrypt ('same text');
+		$encrypted2 = $crypt->encrypt ('same text');
+
+		// Due to random salt, encrypted values should differ
+		$this->assertNotEquals ($encrypted1, $encrypted2);
+	}
+
+	public function testEncryptDecryptEmptyString ()
+	{
+		$crypt = new SimpleCrypt ('password');
+		$encrypted = $crypt->encrypt ('');
+		$decrypted = $crypt->decrypt ($encrypted);
+		$this->assertEquals ('', $decrypted);
+	}
+
+	public function testEncryptDecryptSpecialCharacters ()
+	{
+		$crypt = new SimpleCrypt ('password');
+		$original = "Special chars: !@#\$%^&*()_+-=[]{}|;':\",./<>?";
+
+		$encrypted = $crypt->encrypt ($original);
+		$decrypted = $crypt->decrypt ($encrypted);
+		$this->assertEquals ($original, $decrypted);
+	}
+
+	public function testEncryptDecryptUTF8 ()
+	{
+		$crypt = new SimpleCrypt ('password');
+		$original = 'Héllo Wörld 日本語';
+
+		$encrypted = $crypt->encrypt ($original);
+		$decrypted = $crypt->decrypt ($encrypted);
+		$this->assertEquals ($original, $decrypted);
+	}
+
+	public function testEncryptDecryptWithSaltMarkerInContent ()
+	{
+		$crypt = new SimpleCrypt ('password');
+		$original = 'Text with |||CWSALT inside it';
+
+		$encrypted = $crypt->encrypt ($original);
+		$decrypted = $crypt->decrypt ($encrypted);
+		$this->assertEquals ($original, $decrypted);
+	}
+}
diff --git a/tests/TestDatabase.php b/tests/TestDatabase.php
new file mode 100644
index 0000000..12d1b70
--- /dev/null
+++ b/tests/TestDatabase.php
@@ -0,0 +1,49 @@
+<?php
+
+namespace Neuron\Tests;
+
+use Neuron\DB\Database;
+use Neuron\DB\Result;
+
+/**
+ * A Database stub that performs MySQL-compatible escaping in pure PHP.
+ * Allows Query tests to run without an actual MySQL connection.
+ */
+class TestDatabase extends Database
+{
+	/**
+	 * Escape a string using the same rules as mysqli::real_escape_string.
+	 */
+	public function escape ($txt): string
+	{
+		return strtr ((string) $txt, [
+			"\\"   => "\\\\",
+			"\x00" => "\\0",
+			"\n"   => "\\n",
+			"\r"   => "\\r",
+			"'"    => "\\'",
+			'"'    => '\\"',
+			"\x1a" => "\\Z",
+		]);
+	}
+
+	public function query ($sSQL): int
+	{
+		return 0;
+	}
+
+	public function multiQuery ($sSQL): int
+	{
+		return 0;
+	}
+
+	public function fromUnixtime ($timestamp): string
+	{
+		return date ('Y-m-d H:i:s', $timestamp);
+	}
+
+	public function toUnixtime ($date): int
+	{
+		return strtotime ($date);
+	}
+}
diff --git a/tests/TokenGeneratorTest.php b/tests/TokenGeneratorTest.php
index 2f301e9..a2f1693 100644
--- a/tests/TokenGeneratorTest.php
+++ b/tests/TokenGeneratorTest.php
@@ -3,11 +3,11 @@
 
 namespace Neuron\Tests;
 
-use PHPUnit_Framework_TestCase;
+use PHPUnit\Framework\TestCase;
 
 
 class TokenGeneratorTest
-	extends PHPUnit_Framework_TestCase
+	extends TestCase
 {
 	public function testLengthSimplified ()
 	{
diff --git a/tests/ToolsTest.php b/tests/ToolsTest.php
index 26cae51..6c92292 100644
--- a/tests/ToolsTest.php
+++ b/tests/ToolsTest.php
@@ -3,12 +3,12 @@
 
 namespace Neuron\Tests;
 
-use PHPUnit_Framework_TestCase;
+use PHPUnit\Framework\TestCase;
 use Neuron\Core\Tools;
 
 
 class ToolsTest
-	extends PHPUnit_Framework_TestCase
+	extends TestCase
 {
 	public function testEmailInputCheck ()
 	{
@@ -102,4 +102,487 @@ public function testDateInput () {
 		$this->assertTrue (Tools::checkInput ('2015-06-01T10:00', 'datetime'));
 		$this->assertFalse (Tools::checkInput ('06-01-2015T10:00', 'datetime'));
 	}
+
+	// ---------------------------------------------------------------
+	// Date validation tests (the bug fix)
+	// ---------------------------------------------------------------
+
+	public function testDateCheckInputValidDates ()
+	{
+		$this->assertTrue (Tools::checkInput ('2015-06-01', 'date'));
+		$this->assertTrue (Tools::checkInput ('2000-01-01', 'date'));
+		$this->assertTrue (Tools::checkInput ('1999-12-31', 'date'));
+		$this->assertTrue (Tools::checkInput ('2024-02-29', 'date')); // leap year
+	}
+
+	public function testDateCheckInputInvalidNonIntegerParts ()
+	{
+		// The original bug: "a-b-c" would pass
+		$this->assertFalse (Tools::checkInput ('a-b-c', 'date'));
+		$this->assertFalse (Tools::checkInput ('foo-bar-baz', 'date'));
+		$this->assertFalse (Tools::checkInput ('20xx-01-01', 'date'));
+		$this->assertFalse (Tools::checkInput ('2015-ab-01', 'date'));
+		$this->assertFalse (Tools::checkInput ('2015-01-cd', 'date'));
+	}
+
+	public function testDateCheckInputInvalidDateValues ()
+	{
+		$this->assertFalse (Tools::checkInput ('2015-13-01', 'date')); // month 13
+		$this->assertFalse (Tools::checkInput ('2015-00-01', 'date')); // month 0
+		$this->assertFalse (Tools::checkInput ('2015-02-30', 'date')); // Feb 30
+		$this->assertFalse (Tools::checkInput ('2023-02-29', 'date')); // non-leap year
+		$this->assertFalse (Tools::checkInput ('2015-06-32', 'date')); // day 32
+		$this->assertFalse (Tools::checkInput ('0000-01-01', 'date')); // year 0
+	}
+
+	public function testDateCheckInputInvalidFormats ()
+	{
+		$this->assertFalse (Tools::checkInput ('', 'date'));
+		$this->assertFalse (Tools::checkInput ('2015', 'date'));
+		$this->assertFalse (Tools::checkInput ('2015-06', 'date'));
+		$this->assertFalse (Tools::checkInput ('2015/06/01', 'date'));
+		$this->assertFalse (Tools::checkInput ('01-06-2015', 'date')); // wrong order but valid checkdate would pass
+		$this->assertFalse (Tools::checkInput ('2015-06-01-extra', 'date'));
+	}
+
+	public function testDateGetInputValidDate ()
+	{
+		$dat = array ('date' => '2015-06-01');
+		$result = Tools::getInput ($dat, 'date', 'date');
+		$this->assertIsInt ($result);
+		$this->assertEquals ('2015-06-01', date ('Y-m-d', $result));
+	}
+
+	public function testDateGetInputInvalidDate ()
+	{
+		$dat = array ('date' => 'a-b-c');
+		$result = Tools::getInput ($dat, 'date', 'date');
+		$this->assertNull ($result);
+	}
+
+	public function testDateGetInputMissing ()
+	{
+		$dat = array ();
+		$result = Tools::getInput ($dat, 'date', 'date');
+		$this->assertNull ($result);
+	}
+
+	public function testDateGetInputDefault ()
+	{
+		$dat = array ('date' => 'invalid');
+		$result = Tools::getInput ($dat, 'date', 'date', 'default_value');
+		$this->assertEquals ('default_value', $result);
+	}
+
+	// ---------------------------------------------------------------
+	// Datetime validation tests
+	// ---------------------------------------------------------------
+
+	public function testDatetimeCheckInputValid ()
+	{
+		$this->assertTrue (Tools::checkInput ('2015-06-01T10:00', 'datetime'));
+		$this->assertTrue (Tools::checkInput ('2024-12-31T23:59', 'datetime'));
+	}
+
+	public function testDatetimeCheckInputInvalid ()
+	{
+		$this->assertFalse (Tools::checkInput ('06-01-2015T10:00', 'datetime'));
+		$this->assertFalse (Tools::checkInput ('not-a-datetime', 'datetime'));
+		$this->assertFalse (Tools::checkInput ('2015-06-01 10:00', 'datetime'));
+		$this->assertFalse (Tools::checkInput ('', 'datetime'));
+	}
+
+	public function testDatetimeGetInputValid ()
+	{
+		$dat = array ('dt' => '2015-06-01T10:00');
+		$result = Tools::getInput ($dat, 'dt', 'datetime');
+		$this->assertInstanceOf (\DateTime::class, $result);
+	}
+
+	// ---------------------------------------------------------------
+	// Text and varchar type tests
+	// ---------------------------------------------------------------
+
+	public function testTextCheckInput ()
+	{
+		$this->assertTrue (Tools::checkInput ('anything', 'text'));
+		$this->assertTrue (Tools::checkInput ('', 'text'));
+		$this->assertTrue (Tools::checkInput ('<script>alert(1)</script>', 'text'));
+	}
+
+	public function testVarcharCheckInput ()
+	{
+		$this->assertTrue (Tools::checkInput ('valid text', 'varchar'));
+		$this->assertTrue (Tools::checkInput ('valid text', 'string'));
+		$this->assertTrue (Tools::checkInput ('valid <b>html</b>', 'html'));
+	}
+
+	public function testNameCheckInput ()
+	{
+		$this->assertTrue (Tools::checkInput ('John Doe', 'name'));
+		$this->assertFalse (Tools::checkInput ('<b>John</b>', 'name'));
+		$this->assertFalse (Tools::checkInput ('<script>alert(1)</script>', 'name'));
+	}
+
+	// ---------------------------------------------------------------
+	// Bool type tests
+	// ---------------------------------------------------------------
+
+	public function testBoolCheckInput ()
+	{
+		$this->assertTrue (Tools::checkInput (1, 'bool'));
+		$this->assertTrue (Tools::checkInput ('true', 'bool'));
+		$this->assertFalse (Tools::checkInput (0, 'bool'));
+		$this->assertFalse (Tools::checkInput ('false', 'bool'));
+		$this->assertFalse (Tools::checkInput ('', 'bool'));
+	}
+
+	public function testBoolGetInput ()
+	{
+		// When checkInput passes (value is 1 or 'true'), getInput returns strip_tags(value)
+		$dat = array ('flag' => 1);
+		$this->assertEquals ('1', Tools::getInput ($dat, 'flag', 'bool'));
+
+		$dat = array ('flag' => 'true');
+		$this->assertEquals ('true', Tools::getInput ($dat, 'flag', 'bool'));
+
+		// When bool validation fails, getInput returns false (special case)
+		$dat = array ('flag' => 0);
+		$this->assertFalse (Tools::getInput ($dat, 'flag', 'bool'));
+
+		$dat = array ('flag' => 'no');
+		$this->assertFalse (Tools::getInput ($dat, 'flag', 'bool'));
+	}
+
+	// ---------------------------------------------------------------
+	// Password type tests
+	// ---------------------------------------------------------------
+
+	public function testPasswordCheckInput ()
+	{
+		$this->assertTrue (Tools::checkInput ('password123', 'password'));
+		$this->assertTrue (Tools::checkInput ('12345678', 'password'));
+		$this->assertFalse (Tools::checkInput ('short', 'password'));
+		$this->assertFalse (Tools::checkInput ('1234567', 'password')); // 7 chars
+		$this->assertFalse (Tools::checkInput (str_repeat ('a', 257), 'password')); // too long
+		$this->assertTrue (Tools::checkInput (str_repeat ('a', 256), 'password')); // max allowed
+	}
+
+	// ---------------------------------------------------------------
+	// Username type tests
+	// ---------------------------------------------------------------
+
+	public function testUsernameCheckInput ()
+	{
+		$this->assertTrue (Tools::checkInput ('john_doe', 'username'));
+		$this->assertTrue (Tools::checkInput ('User123', 'username'));
+		$this->assertTrue (Tools::checkInput ('abc', 'username')); // min 3 chars
+		$this->assertFalse (Tools::checkInput ('ab', 'username')); // too short
+		$this->assertFalse (Tools::checkInput ('', 'username'));
+		$this->assertFalse (Tools::checkInput ('user name', 'username')); // space
+		$this->assertFalse (Tools::checkInput ('user@name', 'username')); // special chars
+		$this->assertFalse (Tools::checkInput (str_repeat ('a', 21), 'username')); // too long
+	}
+
+	// ---------------------------------------------------------------
+	// MD5 type tests
+	// ---------------------------------------------------------------
+
+	public function testMd5CheckInput ()
+	{
+		$this->assertTrue (Tools::checkInput (md5 ('test'), 'md5'));
+		$this->assertTrue (Tools::checkInput ('d41d8cd98f00b204e9800998ecf8427e', 'md5'));
+		$this->assertFalse (Tools::checkInput ('tooshort', 'md5'));
+		$this->assertFalse (Tools::checkInput ('', 'md5'));
+		$this->assertFalse (Tools::checkInput (str_repeat ('a', 33), 'md5'));
+	}
+
+	// ---------------------------------------------------------------
+	// Base64 type tests
+	// ---------------------------------------------------------------
+
+	public function testBase64CheckInput ()
+	{
+		$this->assertTrue (Tools::checkInput (base64_encode ('test'), 'base64'));
+		$this->assertTrue (Tools::checkInput (base64_encode ('hello world'), 'base64'));
+		$this->assertFalse (Tools::checkInput ('not valid base64!!!', 'base64'));
+	}
+
+	public function testBase64GetInput ()
+	{
+		$dat = array ('data' => base64_encode ('hello world'));
+		$result = Tools::getInput ($dat, 'data', 'base64');
+		$this->assertEquals ('hello world', $result);
+	}
+
+	// ---------------------------------------------------------------
+	// Raw type tests
+	// ---------------------------------------------------------------
+
+	public function testRawCheckInput ()
+	{
+		$this->assertTrue (Tools::checkInput ('anything', 'raw'));
+		$this->assertTrue (Tools::checkInput ('<script>alert(1)</script>', 'raw'));
+	}
+
+	public function testRawGetInput ()
+	{
+		$dat = array ('data' => '<script>alert(1)</script>');
+		$result = Tools::getInput ($dat, 'data', 'raw');
+		$this->assertEquals ('<script>alert(1)</script>', $result);
+	}
+
+	public function testHtmlGetInput ()
+	{
+		$dat = array ('data' => '<b>bold</b>');
+		$result = Tools::getInput ($dat, 'data', 'html');
+		$this->assertEquals ('<b>bold</b>', $result);
+	}
+
+	// ---------------------------------------------------------------
+	// Unknown type tests
+	// ---------------------------------------------------------------
+
+	public function testUnknownTypeReturnsFalse ()
+	{
+		$this->assertFalse (Tools::checkInput ('value', 'nonexistent_type'));
+	}
+
+	// ---------------------------------------------------------------
+	// getInput default behavior tests
+	// ---------------------------------------------------------------
+
+	public function testGetInputMissingKey ()
+	{
+		$dat = array ();
+		$this->assertNull (Tools::getInput ($dat, 'missing', 'text'));
+	}
+
+	public function testGetInputMissingKeyWithDefault ()
+	{
+		$dat = array ();
+		$this->assertEquals ('fallback', Tools::getInput ($dat, 'missing', 'text', 'fallback'));
+	}
+
+	public function testGetInputStripsTagsByDefault ()
+	{
+		$dat = array ('name' => '<b>John</b> Doe');
+		$result = Tools::getInput ($dat, 'name', 'varchar');
+		$this->assertEquals ('John Doe', $result);
+	}
+
+	// ---------------------------------------------------------------
+	// SQL injection patterns via checkInput
+	// ---------------------------------------------------------------
+
+	public function testSqlInjectionInEmailField ()
+	{
+		$this->assertFalse (Tools::checkInput ("' OR '1'='1", 'email'));
+		$this->assertFalse (Tools::checkInput ("admin@example.com' OR 1=1--", 'email'));
+		$this->assertFalse (Tools::checkInput ("admin@example.com'; DROP TABLE users;--", 'email'));
+		$this->assertFalse (Tools::checkInput ("' UNION SELECT * FROM users--", 'email'));
+	}
+
+	public function testSqlInjectionInUsernameField ()
+	{
+		$this->assertFalse (Tools::checkInput ("' OR '1'='1", 'username'));
+		$this->assertFalse (Tools::checkInput ("admin'; DROP TABLE users;--", 'username'));
+		$this->assertFalse (Tools::checkInput ("admin' UNION SELECT * FROM users--", 'username'));
+		$this->assertFalse (Tools::checkInput ("1; DROP TABLE users", 'username'));
+	}
+
+	public function testSqlInjectionInDateField ()
+	{
+		$this->assertFalse (Tools::checkInput ("'; DROP TABLE users;--", 'date'));
+		$this->assertFalse (Tools::checkInput ("2015-01-01' OR '1'='1", 'date'));
+		$this->assertFalse (Tools::checkInput ("2015-01-01; DROP TABLE users;--", 'date'));
+		$this->assertFalse (Tools::checkInput ("1 OR 1=1", 'date'));
+		$this->assertFalse (Tools::checkInput ("' UNION SELECT * FROM users--", 'date'));
+	}
+
+	public function testSqlInjectionInDatetimeField ()
+	{
+		$this->assertFalse (Tools::checkInput ("'; DROP TABLE users;--", 'datetime'));
+		$this->assertFalse (Tools::checkInput ("not-a-datetime", 'datetime'));
+	}
+
+	public function testSqlInjectionInIntField ()
+	{
+		$this->assertFalse (Tools::checkInput ("1; DROP TABLE users", 'int'));
+		$this->assertFalse (Tools::checkInput ("1 OR 1=1", 'int'));
+		$this->assertFalse (Tools::checkInput ("' OR '1'='1", 'int'));
+		$this->assertFalse (Tools::checkInput ("1 UNION SELECT * FROM users", 'int'));
+	}
+
+	public function testSqlInjectionInNumberField ()
+	{
+		$this->assertFalse (Tools::checkInput ("1; DROP TABLE users", 'number'));
+		$this->assertFalse (Tools::checkInput ("1 OR 1=1", 'number'));
+		$this->assertFalse (Tools::checkInput ("' OR '1'='1", 'number'));
+	}
+
+	public function testSqlInjectionInMd5Field ()
+	{
+		$this->assertFalse (Tools::checkInput ("' OR '1'='1' --", 'md5'));
+		$this->assertFalse (Tools::checkInput ("'; DROP TABLE users;--", 'md5'));
+	}
+
+	public function testSqlInjectionInPasswordField ()
+	{
+		// These pass checkInput because password only checks length/UTF-8
+		// But they should still be properly escaped before use in queries
+		$this->assertTrue (Tools::checkInput ("password' OR '1'='1", 'password'));
+	}
+
+	public function testSqlInjectionInUrlField ()
+	{
+		$this->assertFalse (Tools::checkInput ("'; DROP TABLE users;--", 'url'));
+		$this->assertFalse (Tools::checkInput ("' OR '1'='1", 'url'));
+	}
+
+	// ---------------------------------------------------------------
+	// XSS injection patterns via getInput
+	// ---------------------------------------------------------------
+
+	public function testXssStrippedByGetInputDefault ()
+	{
+		$dat = array ('name' => '<script>alert("xss")</script>');
+		$result = Tools::getInput ($dat, 'name', 'varchar');
+		$this->assertStringNotContainsString ('<script>', $result);
+	}
+
+	public function testXssStrippedByGetInputName ()
+	{
+		// The 'name' type rejects values with HTML tags
+		$dat = array ('name' => '<img src=x onerror=alert(1)>');
+		$result = Tools::getInput ($dat, 'name', 'name');
+		$this->assertNull ($result);
+	}
+
+	// ---------------------------------------------------------------
+	// UTF-8 validation tests
+	// ---------------------------------------------------------------
+
+	public function testIsValidUTF8 ()
+	{
+		$this->assertTrue (Tools::isValidUTF8 ('hello'));
+		$this->assertTrue (Tools::isValidUTF8 ('héllo wörld'));
+		$this->assertTrue (Tools::isValidUTF8 ('日本語'));
+		$this->assertTrue (Tools::isValidUTF8 (''));
+		$this->assertFalse (Tools::isValidUTF8 ("\xFF\xFE"));
+	}
+
+	// ---------------------------------------------------------------
+	// isValidBase64 tests
+	// ---------------------------------------------------------------
+
+	public function testIsValidBase64 ()
+	{
+		$this->assertTrue (Tools::isValidBase64 (base64_encode ('test')));
+		$this->assertTrue (Tools::isValidBase64 (base64_encode ('hello world')));
+		$this->assertFalse (Tools::isValidBase64 ('not valid!!!'));
+	}
+
+	// ---------------------------------------------------------------
+	// putIntoText tests
+	// ---------------------------------------------------------------
+
+	public function testPutIntoText ()
+	{
+		$result = Tools::putIntoText ('Hello @@name, you are @@age years old.', array ('name' => 'John', 'age' => 30));
+		$this->assertEquals ('Hello John, you are 30 years old.', $result);
+	}
+
+	public function testPutIntoTextRemovesUnmatched ()
+	{
+		$result = Tools::putIntoText ('Hello @@name, your @@missing value.', array ('name' => 'John'));
+		$this->assertEquals ('Hello John, your  value.', $result);
+	}
+
+	public function testPutIntoTextWithObject ()
+	{
+		$obj = new class {
+			public function __toString () { return 'StringObj'; }
+		};
+		$result = Tools::putIntoText ('Value: @@val', array ('val' => $obj));
+		$this->assertEquals ('Value: StringObj', $result);
+	}
+
+	public function testPutIntoTextThrowsOnInvalidValue ()
+	{
+		$this->expectException (\Exception::class);
+		Tools::putIntoText ('Hello @@val', array ('val' => array ('nested')));
+	}
+
+	// ---------------------------------------------------------------
+	// output_text tests
+	// ---------------------------------------------------------------
+
+	public function testOutputText ()
+	{
+		$result = Tools::output_text ("Hello\nWorld");
+		$this->assertStringContainsString ('<br', $result);
+	}
+
+	// ---------------------------------------------------------------
+	// output_datepicker tests
+	// ---------------------------------------------------------------
+
+	public function testOutputDatepicker ()
+	{
+		$timestamp = mktime (0, 0, 0, 6, 15, 2020);
+		$result = Tools::output_datepicker ($timestamp);
+		$this->assertEquals ('2020-06-15', $result);
+	}
+
+	public function testOutputDatepickerEmpty ()
+	{
+		$result = Tools::output_datepicker (null);
+		$this->assertEquals ('', $result);
+	}
+
+	// ---------------------------------------------------------------
+	// splitLongWords tests
+	// ---------------------------------------------------------------
+
+	public function testSplitLongWords ()
+	{
+		$long = str_repeat ('a', 40);
+		$result = Tools::splitLongWords ($long);
+		$this->assertStringContainsString (' ', $result);
+	}
+
+	public function testSplitLongWordsShortInput ()
+	{
+		$result = Tools::splitLongWords ('short');
+		$this->assertEquals ('short', $result);
+	}
+
+	// ---------------------------------------------------------------
+	// output_form tests
+	// ---------------------------------------------------------------
+
+	public function testOutputForm ()
+	{
+		$result = Tools::output_form ('<script>alert("xss")</script>');
+		$this->assertStringNotContainsString ('<script>', $result);
+		$this->assertStringContainsString ('&lt;script&gt;', $result);
+	}
+
+	public function testOutputFormQuotes ()
+	{
+		$result = Tools::output_form ("He said \"hello\" and it's fine");
+		$this->assertStringNotContainsString ('"', $result);
+		$this->assertStringContainsString ('&quot;', $result);
+	}
+
+	// ---------------------------------------------------------------
+	// output_varchar tests
+	// ---------------------------------------------------------------
+
+	public function testOutputVarchar ()
+	{
+		$result = Tools::output_varchar ('<b>bold</b>');
+		$this->assertStringContainsString ('&lt;b&gt;', $result);
+	}
 }
\ No newline at end of file
diff --git a/tests/URLBuilderTest.php b/tests/URLBuilderTest.php
new file mode 100644
index 0000000..17fb31a
--- /dev/null
+++ b/tests/URLBuilderTest.php
@@ -0,0 +1,59 @@
+<?php
+
+namespace Neuron\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Neuron\URLBuilder;
+
+class URLBuilderTest extends TestCase
+{
+	public function testNormalize ()
+	{
+		// Note: normalize has a known bug where it uses substr($path, 0, -1) 
+		// instead of substr($path, -1) for the check. Testing actual behavior.
+		$this->assertEquals ('http://example.com', URLBuilder::normalize ('http://example.com'));
+	}
+
+	public function testPartify ()
+	{
+		$this->assertEquals ('http://example.com/', URLBuilder::partify ('http://example.com'));
+		$this->assertEquals ('http://example.com/', URLBuilder::partify ('http://example.com/'));
+	}
+
+	public function testGetURLSimple ()
+	{
+		$url = URLBuilder::getURL ('page', array (), true, 'http://example.com/');
+		$this->assertEquals ('http://example.com/page', $url);
+	}
+
+	public function testGetURLWithParams ()
+	{
+		$url = URLBuilder::getURL ('search', array ('q' => 'test'), true, 'http://example.com/');
+		$this->assertStringContainsString ('q=test', $url);
+		$this->assertStringContainsString ('search', $url);
+	}
+
+	public function testGetURLWithLeadingSlash ()
+	{
+		$url = URLBuilder::getURL ('/page', array (), true, 'http://example.com/');
+		$this->assertEquals ('http://example.com/page', $url);
+	}
+
+	public function testGetURLNoNormalize ()
+	{
+		$url = URLBuilder::getURL ('page', array (), false, 'http://example.com/');
+		$this->assertEquals ('http://example.com/page', $url);
+	}
+
+	public function testGetURLWithParamsNoNormalize ()
+	{
+		$url = URLBuilder::getURL ('search', array ('q' => 'test'), false, 'http://example.com/');
+		$this->assertStringContainsString ('q=test', $url);
+	}
+
+	public function testGetURLSpecialCharsInParams ()
+	{
+		$url = URLBuilder::getURL ('page', array ('name' => 'John Doe'), true, 'http://example.com/');
+		$this->assertStringContainsString ('name=John+Doe', $url);
+	}
+}