diff --git a/README.md b/README.md
index 2ccbf4ac..a6da378d 100644
--- a/README.md
+++ b/README.md
@@ -4,108 +4,9 @@ Tools for creating PHP classes from the HL7 FHIR Specification
 If you're looking  to use the classes generated by this library, you may want the
 [php-fhir-generated](https://github.com/dcarbone/php-fhir-generated) repo instead.
 
-<!-- TOC -->
-* [php-fhir](#php-fhir)
-* [Install as Standalone Generator](#install-as-standalone-generator)
-* [Install as Library](#install-as-library)
-* [Version Table](#version-table)
-* [Basic Usage](#basic-usage)
-  * [Class Generation](#class-generation)
-    * [Generation Example](#generation-example)
-  * [Data Querying](#data-querying)
-  * [Response Parsing](#response-parsing)
-  * [Parsing Example](#parsing-example)
-* [Serialization](#serialization)
-  * [JSON Serialization](#json-serialization)
-  * [XML Serialization](#xml-serialization)
-* [Testing](#testing)
-  * [TODO](#todo)
-  * [Suggestions and help](#suggestions-and-help)
-<!-- TOC -->
-
-# Install as Standalone Generator
-If you wish to use this package as a standalone generator:
- 
-1. Check out the desired branch or tag
-2. Execute `composer install` from root of project directory
-3. Execute `./bin/generate.sh`
-4. Answer all prompts
-   * If no custom configuration file is defined, definitions will be downloaded to `./input` and
-classes will be generated under `./output` 
-   * You can execute `./bin/generate.sh --help` for details on how to utilize this script
-   * You can configure various aspects of this script by altering the values in [./bin/config.php](./bin/config.php)
-
-This script will download configured major versions of FHIR into the `input` folder and
-generate classes for every version in the `output` folder.
-
-# Install as Library
-If you wish to use the generator as part of a project, you can include it as a composer
-dependency:
-
-```shell
-composer require dcarbone/php-fhir
-```
-
-From there, you can reference the [Example](#generation-example) block for a quick example on how to
-configure and execute the generator.
-
-# Version Table
-
-| PHPFHIR Version | PHP Versions | FHIR Versions                    |
-|-----------------|--------------|----------------------------------|
-| v2              | 5.4-7.4      | DSTU1, DSTU2, STU3, R4 (<v4.3.0) |
-| v3              | 8.1+         | DSTU1, DSTU2, STU3, R4, R5       |
-
-# Basic Usage
-
-The first step is to determine the version of the FHIR spec your implementation supports.  Once done, download
-the appropriate class definition XSDs from [http://hl7.org/fhir/directory.html](http://hl7.org/fhir/directory.html).
-
-Uncompress the XSD's and place them in a directory that is readable by PHP's runtime user.
-
-Next comes the fun:
-
-## Class Generation
-
-The class generator utility included with this library is designed to parse the XSD's provided by the FHIR
-group into PHP classes, complete with markup and type hinting.
-
-There are 2 important things to note with this section:
-
-1. Your exact implementation will probably vary, don't hesitate to ask if you need some help
-2. The class generation should be run ONCE per FHIR version.  Once the classes have been generated they should only 
-   ever be re-generated if your server switches to a new FHIR spec
-
-### Generation Example
-
-You can view an example config array here: [bin/config.php](./bin/config.php).
-
-```php
-// first, build new configuration class
-$config = new \DCarbone\PHPFHIR\Config(require 'config.php');
-
-// if you wish to limit the versions generated to a subset of those configured:
-// $config->setVersionsToGenerate(['DSTU2', 'STU3']);
-
-// next, iterate through all configured versions and render code:
-foreach ($config->getVersionsIterator() as $versionConfig) {
-    $versionConfig->getDefinition()->getBuilder()->render();
-}
-```
-
-## Data Querying
-
-Currently only a very simple client intended for debugging use is generated.  A future goal is to generate a more
-fully-featured client.
-
-## Response Parsing
-
-As part of the class generation above, a response parsing class called `PHPFHIRResponseParser` will be created
-and added into the root namespace directory.  It currently supports JSON and XML response types.
+# Documentation
 
-The parser class takes a single optional boolean argument that will determine if it should
-attempt to load up the generated Autoloader class.  By default it will do so, but you are free to configure your
-own autoloader and not use the generated one if you wish.
+Please refer to our wiki for the latest documentation: https://github.com/dcarbone/php-fhir/wiki
 
 ## Parsing Example
 
diff --git a/src/Version/DefaultConfig.php b/src/Version/DefaultConfig.php
index ff5ff377..24b72799 100644
--- a/src/Version/DefaultConfig.php
+++ b/src/Version/DefaultConfig.php
@@ -57,13 +57,28 @@ public function setUnserializeConfig(array $config): self
         if ([] === $config) {
             return $this;
         }
-        if (isset($config['libxmlOpts']) && isset($config['libxmlOptMask'])) {
+        if (array_key_exists('libxmlOpts', $config) && array_key_exists('libxmlOptMask', $config)) {
             throw new \DomainException('Cannot specify both "libxmlOpts" and "libxmlOptMask" keys.');
         }
         foreach (self::_UNSERIALIZE_CONFIG_KEYS as $k) {
-            if (isset($config[$k]) || array_key_exists($k, $config)) {
-                $this->_unserializeConfig[$k] = $config[$k];
+            if (!array_key_exists($k, $config)) {
+                continue;
             }
+            $this->_unserializeConfig[$k] = match ($k) {
+                'libxmlOpts' => intval($config[$k]),
+                'libxmlOptMask' => is_string($config[$k]) && preg_match('{^[A-Z0-9_\s|]+}$}', $config[$k])
+                    ? $config[$k]
+                    : throw new \InvalidArgumentException(sprintf(
+                        'Value provided to "libxmlOptMask" is either not a string or is an invalid options mask: %s',
+                        $config[$k],
+                    )),
+                'jsonDecodeMaxDepth' => intval($config[$k]),
+
+                default => throw new \UnexpectedValueException(sprintf(
+                    'Unknown unserialize config key "%s"',
+                    $k,
+                ))
+            };
         }
         return $this;
     }
@@ -87,8 +102,22 @@ public function setSerializeConfig(array $config): self
             return $this;
         }
         foreach (self::_SERIALIZE_CONFIG_KEYS as $k) {
-            if (isset($config[$k]) || array_key_exists($k, $config)) {
-                $this->_serializeConfig[$k] = $config[$k];
+            if (!array_key_exists($k, $config)) {
+                continue;
+            }
+            $this->_serializeConfig[$k] = match ($k) {
+                'overrideSourceXMLNS' => (bool)$config[$k],
+                'rootXMLNS' => null === $config[$k] ? null : (string)$config[$k],
+
+                default => throw new \UnexpectedValueException(sprintf(
+                    'Unknown serialize config key "%s"',
+                    $k,
+                ))
+            };
+            if ($this->_serializeConfig['overrideSourceXMLNS'] ?? false) {
+                if (!isset($this->_serializeConfig['rootXMLNS']) || '' === $this->_serializeConfig['rootXMLNS']) {
+                    throw new \DomainException('Must specify rootXMLNS if overrideSourceXMLNS is true');
+                }
             }
         }
         return $this;
diff --git a/template/core/class_autoloader.php b/template/core/class_autoloader.php
index 0329ccda..cb85ee14 100644
--- a/template/core/class_autoloader.php
+++ b/template/core/class_autoloader.php
@@ -36,6 +36,19 @@ abstract class <?php echo PHPFHIR_CLASSNAME_AUTOLOADER; ?>
 {
     private const _ROOT_NAMESPACE = '<?php echo $config->getFullyQualifiedName(false); ?>\\';
 
+    private const _VERSION_AUTOLOADER_MAP = [
+<?php foreach($config->getVersionsIterator() as $i => $version): ?>
+        <?php echo $i; ?> => [
+            '<?php echo $version->getFullyQualifiedName(false); ?>\\',
+            '<?php echo $version->getFullyQualifiedName(false, PHPFHIR_CLASSNAME_AUTOLOADER); ?>',
+            <?php echo FileUtils::buildAutoloaderRelativeFilepath(
+                $config->getFullyQualifiedName(false),
+                $version->getFullyQualifiedName(false, PHPFHIR_CLASSNAME_AUTOLOADER),
+            ); ?>,
+        ],
+<?php endforeach; ?>
+    ];
+
     private const _CORE_CLASS_MAP = [
         // core types
 <?php foreach($config->getCoreFiles()->getIterator() as $coreFile): if ($coreFile->isAutoloader() || $coreFile->isTest()) { continue; } ?>
@@ -47,10 +60,16 @@ abstract class <?php echo PHPFHIR_CLASSNAME_AUTOLOADER; ?>
 
     private static bool $_registered = false;
 
+    private static array $_versionRegistered = [
+<?php foreach($config->getVersionsIterator() as $i => $version) : ?>
+        <?php echo $i; ?> => false,
+<?php endforeach; ?>
+    ];
+
     public static function register(): bool
     {
         if (!self::$_registered) {
-            self::$_registered = spl_autoload_register(__CLASS__ . '::loadClass', true);
+            self::$_registered = spl_autoload_register(__CLASS__ . '::loadClass');
         }
         return self::$_registered;
     }
@@ -72,22 +91,18 @@ public static function loadClass(string $class): null|bool
             return (bool)require self::_CORE_CLASS_MAP[$class];
         } else if (!str_starts_with($class, self::_ROOT_NAMESPACE)) {
             return null;
-        }<?php foreach($config->getVersionsIterator() as $version): ?> else if (str_starts_with($class, '<?php echo $version->getFullyQualifiedName(false); ?>\\')) {
-            if (!class_exists('<?php echo $version->getFullyQualifiedName(true, PHPFHIR_CLASSNAME_AUTOLOADER); ?>', false)) {
-                if (((bool)require <?php echo FileUtils::buildAutoloaderRelativeFilepath(
-                    $config->getFullyQualifiedName(false),
-                    $version->getFullyQualifiedName(false, PHPFHIR_CLASSNAME_AUTOLOADER),
-                ); ?>) && <?php echo $version->getFullyQualifiedName(true, PHPFHIR_CLASSNAME_AUTOLOADER); ?>::register()) {
-                    if ($class !== '<?php echo $version->getFullyQualifiedName(false, PHPFHIR_CLASSNAME_AUTOLOADER); ?>') {
-                        return <?php echo $version->getFullyQualifiedName(true, PHPFHIR_CLASSNAME_AUTOLOADER); ?>::loadClass($class);
-                    } else {
-                        return true;
-                    }
-                } else {
-                    return false;
-                }
+        }<?php foreach($config->getVersionsIterator() as $i => $version): ?> else if (str_starts_with($class, self::_VERSION_AUTOLOADER_MAP[<?php echo $i; ?>][0])) {
+            if (self::$_versionRegistered[<?php echo $i; ?>]) {
+                return null;
+            }
+            require self::_VERSION_AUTOLOADER_MAP[<?php echo $i; ?>][2];
+            <?php echo $version->getFullyQualifiedName(true, PHPFHIR_CLASSNAME_AUTOLOADER); ?>::register();
+            self::$_versionRegistered[<?php echo $i; ?>] = true;
+            if ($class !== self::_VERSION_AUTOLOADER_MAP[<?php echo $i; ?>][1]) {
+                return <?php echo $version->getFullyQualifiedName(true, PHPFHIR_CLASSNAME_AUTOLOADER); ?>::loadClass($class);
+            } else {
+                return true;
             }
-            return null;
         }<?php endforeach; ?> else {
             return null;
         }