diff --git a/src/Pool/Descriptor.php b/src/Pool/Descriptor.php
deleted file mode 100644
index 74bd111..0000000
--- a/src/Pool/Descriptor.php
+++ /dev/null
@@ -1,39 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Thesis\Protobuf\Pool;
-
-/**
- * @api
- */
-final class Descriptor
-{
-    /** @phpstan-ignore property.uninitialized */
-    public private(set) string $bytes { get => $this->bytes ??= ($this->decode)($this->buffer); }
-
-    /**
-     * @param non-empty-string $buffer
-     */
-    public static function base64(string $buffer): self
-    {
-        return new self($buffer, \base64_decode(...)); // @phpstan-ignore argument.type
-    }
-
-    /**
-     * @param non-empty-string $buffer
-     */
-    public static function raw(string $buffer): self
-    {
-        return new self($buffer, static fn(string $buffer) => $buffer);
-    }
-
-    /**
-     * @param non-empty-string $buffer
-     * @param \Closure(non-empty-string): non-empty-string $decode
-     */
-    private function __construct(
-        private readonly string $buffer,
-        private readonly \Closure $decode,
-    ) {}
-}
diff --git a/src/Pool/File.php b/src/Pool/File.php
deleted file mode 100644
index 4fd30dc..0000000
--- a/src/Pool/File.php
+++ /dev/null
@@ -1,26 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Thesis\Protobuf\Pool;
-
-/**
- * @api
- */
-final readonly class File
-{
-    /**
-     * @param non-empty-string $name
-     * @param list<non-empty-string> $dependencies
-     * @param list<File\MessageDescriptor> $messages
-     * @param list<File\EnumDescriptor> $enums
-     * @param list<File\ServiceDescriptor> $services
-     */
-    public function __construct(
-        public string $name,
-        public array $dependencies = [],
-        public array $messages = [],
-        public array $enums = [],
-        public array $services = [],
-    ) {}
-}
diff --git a/src/Pool/File/EnumDescriptor.php b/src/Pool/File/EnumDescriptor.php
deleted file mode 100644
index f5152ae..0000000
--- a/src/Pool/File/EnumDescriptor.php
+++ /dev/null
@@ -1,20 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Thesis\Protobuf\Pool\File;
-
-/**
- * @api
- */
-final readonly class EnumDescriptor
-{
-    /**
-     * @param non-empty-string $name
-     * @param class-string $fqcn
-     */
-    public function __construct(
-        public string $name,
-        public string $fqcn,
-    ) {}
-}
diff --git a/src/Pool/File/MessageDescriptor.php b/src/Pool/File/MessageDescriptor.php
deleted file mode 100644
index 8a170c1..0000000
--- a/src/Pool/File/MessageDescriptor.php
+++ /dev/null
@@ -1,20 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Thesis\Protobuf\Pool\File;
-
-/**
- * @api
- */
-final readonly class MessageDescriptor
-{
-    /**
-     * @param non-empty-string $name
-     * @param class-string $fqcn
-     */
-    public function __construct(
-        public string $name,
-        public string $fqcn,
-    ) {}
-}
diff --git a/src/Pool/File/ServiceDescriptor.php b/src/Pool/File/ServiceDescriptor.php
deleted file mode 100644
index 9479d90..0000000
--- a/src/Pool/File/ServiceDescriptor.php
+++ /dev/null
@@ -1,22 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Thesis\Protobuf\Pool\File;
-
-/**
- * @api
- */
-final readonly class ServiceDescriptor
-{
-    /**
-     * @param non-empty-string $name
-     * @param ?class-string $clientFqcn
-     * @param ?class-string $serverFqcn
-     */
-    public function __construct(
-        public string $name,
-        public ?string $clientFqcn = null,
-        public ?string $serverFqcn = null,
-    ) {}
-}
diff --git a/src/Pool/OnceRegistrar.php b/src/Pool/OnceRegistrar.php
deleted file mode 100644
index b557ebe..0000000
--- a/src/Pool/OnceRegistrar.php
+++ /dev/null
@@ -1,29 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Thesis\Protobuf\Pool;
-
-/**
- * @api
- */
-final readonly class OnceRegistrar implements Registrar
-{
-    public function __construct(
-        private Registrar $registrar,
-    ) {}
-
-    #[\Override]
-    public function register(Registry $pool): void
-    {
-        /** @var array<class-string<Registrar>, true> $registered */
-        static $registered = [];
-
-        $fqcn = $this->registrar::class;
-
-        if (!isset($registered[$fqcn])) {
-            $pool->register($this->registrar);
-            $registered[$fqcn] = true;
-        }
-    }
-}
diff --git a/src/Pool/Registrar.php b/src/Pool/Registrar.php
deleted file mode 100644
index 8dc5fb7..0000000
--- a/src/Pool/Registrar.php
+++ /dev/null
@@ -1,17 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Thesis\Protobuf\Pool;
-
-/**
- * @api
- */
-interface Registrar
-{
-    /**
-     * Each implementation must ensure that it has not registered its descriptors yet,
-     * or the user must wrap it in a {@see OnceRegistrar}.
-     */
-    public function register(Registry $pool): void;
-}
diff --git a/src/Pool/Registry.php b/src/Pool/Registry.php
deleted file mode 100644
index d094d8f..0000000
--- a/src/Pool/Registry.php
+++ /dev/null
@@ -1,189 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Thesis\Protobuf\Pool;
-
-/**
- * @api
- */
-final class Registry
-{
-    private static self $instance;
-
-    public static function get(): self
-    {
-        return self::$instance ??= new self();
-    }
-
-    /** @var array<non-empty-string, Descriptor> */
-    private array $descriptors = [];
-
-    /** @var array<non-empty-string, File> */
-    private array $files = [];
-
-    /** @var array<non-empty-string, File\MessageDescriptor> map File\MessageDescriptor by typename, used by google.protobuf.Any */
-    private array $messages = [];
-
-    /** @var array<non-empty-string, File\EnumDescriptor> map File\EnumDescriptor by typename */
-    private array $enums = [];
-
-    /** @var array<non-empty-string, File\ServiceDescriptor> map File\ServiceDescriptor by typename, used by server reflection */
-    private array $services = [];
-
-    /** @var array<class-string, non-empty-string> map typename by fqcn, used by google.protobuf.Any */
-    private array $types = [];
-
-    /** @var array<non-empty-string, non-empty-string> map filename by typename, used by server reflection */
-    private array $symbols = [];
-
-    /**
-     * @param non-empty-string $type
-     */
-    public function messageDescriptorByType(string $type): File\MessageDescriptor
-    {
-        return $this->messages[$type] ?? self::throwTypeNotFound($type);
-    }
-
-    /**
-     * @param class-string $fqcn
-     * @return non-empty-string
-     */
-    public function classType(string $fqcn): string
-    {
-        return $this->types[$fqcn] ?? self::throwClassTypeNotFound($fqcn);
-    }
-
-    /**
-     * @param non-empty-string $type
-     */
-    public function enumDescriptorByType(string $type): File\EnumDescriptor
-    {
-        return $this->enums[$type] ?? self::throwTypeNotFound($type);
-    }
-
-    /**
-     * @param class-string $fqcn
-     * @return non-empty-string
-     */
-    public function enumType(string $fqcn): string
-    {
-        return $this->types[$fqcn] ?? self::throwEnumTypeNotFound($fqcn);
-    }
-
-    /**
-     * @param non-empty-string $type
-     */
-    public function serviceDescriptorByType(string $type): File\ServiceDescriptor
-    {
-        return $this->services[$type] ?? self::throwTypeNotFound($type);
-    }
-
-    /**
-     * @param non-empty-string $filename
-     */
-    public function fileByName(string $filename): File
-    {
-        return $this->files[$filename] ?? self::throwTypeNotFound($filename);
-    }
-
-    /**
-     * @param non-empty-string $symbol
-     */
-    public function fileBySymbol(string $symbol): File
-    {
-        return $this->files[$this->symbols[$symbol] ?? self::throwTypeNotFound($symbol)] ?? self::throwTypeNotFound($symbol);
-    }
-
-    /**
-     * @param non-empty-string $filename
-     */
-    public function descriptorByFilename(string $filename): Descriptor
-    {
-        return $this->descriptors[$filename] ?? self::throwTypeNotFound($filename);
-    }
-
-    public function register(Registrar ...$registries): self
-    {
-        $pool = self::get();
-
-        foreach ($registries as $registry) {
-            $registry->register($pool);
-        }
-
-        return $pool;
-    }
-
-    public function add(Descriptor $descriptor, File $file): self
-    {
-        $pool = self::get();
-
-        $pool->descriptors[$file->name] = $descriptor;
-        $pool->files[$file->name] = $file;
-
-        foreach ($file->messages as $message) {
-            if (isset($pool->messages[$message->name])) {
-                self::throwTypeAlreadyRegistered($message->name);
-            }
-
-            $pool->messages[$message->name] = $message;
-            $pool->symbols[$message->name] = $file->name;
-            $pool->types[$message->fqcn] = $message->name;
-        }
-
-        foreach ($file->enums as $enum) {
-            if (isset($pool->enums[$enum->name])) {
-                self::throwTypeAlreadyRegistered($enum->name);
-            }
-
-            $pool->enums[$enum->name] = $enum;
-            $pool->symbols[$enum->name] = $file->name;
-            $pool->types[$enum->fqcn] = $enum->name;
-        }
-
-        foreach ($file->services as $service) {
-            if (isset($pool->services[$service->name])) {
-                self::throwTypeAlreadyRegistered($service->name);
-            }
-
-            $pool->services[$service->name] = $service;
-            $pool->symbols[$service->name] = $file->name;
-        }
-
-        return $pool;
-    }
-
-    /**
-     * @param non-empty-string $type
-     */
-    private static function throwTypeAlreadyRegistered(string $type): never
-    {
-        throw new \RuntimeException(\sprintf('Type "%s" is already registered in the \Thesis\Protobuf\Pool\Registry. Ensure that you are using protobuf compiler correctly, or use \Thesis\Protobuf\Pool\OnceRegistrar to prevent duplicate registration of types in the pool', $type));
-    }
-
-    /**
-     * @param class-string $fqcn
-     */
-    private static function throwClassTypeNotFound(string $fqcn): never
-    {
-        throw new \RuntimeException(\sprintf('Associated with class "%s" metadata not found in the \Thesis\Protobuf\Pool\Registry. Perhaps you forgot to include autoload.metadata.php in composer.json or did not call the appropriate descriptor registrar to register types in the pool?', $fqcn));
-    }
-
-    /**
-     * @param class-string $fqcn
-     */
-    private static function throwEnumTypeNotFound(string $fqcn): never
-    {
-        throw new \RuntimeException(\sprintf('Associated with enum "%s" metadata not found in the \Thesis\Protobuf\Pool\Registry. Perhaps you forgot to include autoload.metadata.php in composer.json or did not call the appropriate descriptor registrar to register types in the pool?', $fqcn));
-    }
-
-    /**
-     * @param non-empty-string $type
-     */
-    private static function throwTypeNotFound(string $type): never
-    {
-        throw new \RuntimeException(\sprintf('Type metadata "%s" not found in the \Thesis\Protobuf\Pool\Registry. Perhaps you forgot to include autoload.metadata.php in composer.json or did not call the appropriate descriptor registrar to register types in the pool?', $type));
-    }
-
-    private function __construct() {}
-}
diff --git a/tests/Pool/RegistryTest.php b/tests/Pool/RegistryTest.php
deleted file mode 100644
index 0b6bee8..0000000
--- a/tests/Pool/RegistryTest.php
+++ /dev/null
@@ -1,116 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Thesis\Protobuf\Pool;
-
-use PHPUnit\Framework\Attributes\CoversClass;
-use PHPUnit\Framework\TestCase;
-
-#[CoversClass(Registry::class)]
-final class RegistryTest extends TestCase
-{
-    public function testMessageRegistered(): void
-    {
-        $pool = Registry::get();
-        $pool->add($descriptor = Descriptor::raw('xyz'), $file = new File(
-            name: 'api.proto',
-            messages: [
-                $md = new File\MessageDescriptor(
-                    name: 'thesis.api.Request',
-                    fqcn: \stdClass::class,
-                ),
-            ],
-        ));
-
-        self::assertEquals($md, $pool->messageDescriptorByType('thesis.api.Request'));
-        self::assertEquals('thesis.api.Request', $pool->classType(\stdClass::class));
-        self::assertEquals($file, $pool->fileBySymbol('thesis.api.Request'));
-        self::assertEquals($descriptor, $pool->descriptorByFilename($file->name));
-        $this->expectExceptionObject(new \RuntimeException('Type "thesis.api.Request" is already registered in the \Thesis\Protobuf\Pool\Registry. Ensure that you are using protobuf compiler correctly, or use \Thesis\Protobuf\Pool\OnceRegistrar to prevent duplicate registration of types in the pool'));
-        $pool->add($descriptor, new File(
-            name: 'api.proto',
-            messages: [
-                new File\MessageDescriptor(
-                    name: 'thesis.api.Request',
-                    fqcn: \stdClass::class,
-                ),
-            ],
-        ));
-    }
-
-    public function testEnumRegistered(): void
-    {
-        $pool = Registry::get();
-        $pool->add($descriptor = Descriptor::raw('xyz'), $file = new File(
-            name: 'api.proto',
-            enums: [
-                $md = new File\EnumDescriptor(
-                    name: 'thesis.api.RequestType',
-                    fqcn: \stdClass::class,
-                ),
-            ],
-        ));
-
-        self::assertEquals($md, $pool->enumDescriptorByType('thesis.api.RequestType'));
-        self::assertEquals('thesis.api.RequestType', $pool->enumType(\stdClass::class));
-        self::assertEquals($file, $pool->fileBySymbol('thesis.api.RequestType'));
-        self::assertEquals($descriptor, $pool->descriptorByFilename($file->name));
-
-        $this->expectExceptionObject(new \RuntimeException('Type "thesis.api.RequestType" is already registered in the \Thesis\Protobuf\Pool\Registry. Ensure that you are using protobuf compiler correctly, or use \Thesis\Protobuf\Pool\OnceRegistrar to prevent duplicate registration of types in the pool'));
-        $pool->add($descriptor, new File(
-            name: 'api.proto',
-            enums: [
-                new File\EnumDescriptor(
-                    name: 'thesis.api.RequestType',
-                    fqcn: \stdClass::class,
-                ),
-            ],
-        ));
-    }
-
-    public function testServiceRegistered(): void
-    {
-        $pool = Registry::get();
-        $pool->add($descriptor = Descriptor::raw('xyz'), $file = new File(
-            name: 'api.proto',
-            services: [
-                $md = new File\ServiceDescriptor(
-                    name: 'thesis.api.RequestService',
-                    clientFqcn: \stdClass::class,
-                ),
-            ],
-        ));
-
-        self::assertEquals($md, $pool->serviceDescriptorByType('thesis.api.RequestService'));
-        self::assertEquals($file, $pool->fileBySymbol('thesis.api.RequestService'));
-        self::assertEquals($descriptor, $pool->descriptorByFilename($file->name));
-
-        $this->expectExceptionObject(new \RuntimeException('Type "thesis.api.RequestService" is already registered in the \Thesis\Protobuf\Pool\Registry. Ensure that you are using protobuf compiler correctly, or use \Thesis\Protobuf\Pool\OnceRegistrar to prevent duplicate registration of types in the pool'));
-        $pool->add($descriptor, new File(
-            name: 'api.proto',
-            services: [
-                new File\ServiceDescriptor(
-                    name: 'thesis.api.RequestService',
-                    clientFqcn: \stdClass::class,
-                ),
-            ],
-        ));
-    }
-
-    public function testTypeNotFound(): void
-    {
-        $pool = Registry::get();
-
-        self::expectExceptionObject(new \RuntimeException('Type metadata "thesis.api.OtherRequest" not found in the \Thesis\Protobuf\Pool\Registry. Perhaps you forgot to include autoload.metadata.php in composer.json or did not call the appropriate descriptor registrar to register types in the pool?'));
-        $pool->messageDescriptorByType('thesis.api.OtherRequest');
-    }
-
-    public function testClassNotFound(): void
-    {
-        $pool = Registry::get();
-
-        self::expectExceptionObject(new \RuntimeException('Associated with class "Thesis\Protobuf\Pool\RegistryTest" metadata not found in the \Thesis\Protobuf\Pool\Registry. Perhaps you forgot to include autoload.metadata.php in composer.json or did not call the appropriate descriptor registrar to register types in the pool?'));
-        $pool->classType(self::class);
-    }
-}