diff --git a/Makefile b/Makefile
index 1f2184851..7e9d2f553 100644
--- a/Makefile
+++ b/Makefile
@@ -22,6 +22,8 @@ update: ## Update dependencies
 	$(DC_RUN_PHP) env XDEBUG_MODE=off composer update
 update-lowest: ## Update dependencies to lowest supported versions
 	$(DC_RUN_PHP) env XDEBUG_MODE=off composer update --prefer-lowest
+dump: ## Dump autoload
+	$(DC_RUN_PHP) env XDEBUG_MODE=off composer dump-autoload
 test: test-unit test-integration ## Run unit and integration tests
 test-unit: ## Run unit tests
 	$(DC_RUN_PHP) env XDEBUG_MODE=coverage vendor/bin/phpunit --testsuite unit --colors=always
diff --git a/composer.json b/composer.json
index ef494a888..026a57a91 100644
--- a/composer.json
+++ b/composer.json
@@ -44,7 +44,8 @@
         "open-telemetry/exporter-otlp": "1.0.x-dev",
         "open-telemetry/exporter-zipkin": "1.0.x-dev",
         "open-telemetry/extension-propagator-b3": "1.0.x-dev",
-        "open-telemetry/extension-propagator-jaeger": "0.0.2",
+        "open-telemetry/extension-propagator-cloudtrace": "0.0.4",
+        "open-telemetry/extension-propagator-jaeger": "0.0.3",
         "open-telemetry/gen-otlp-protobuf": "1.0.x-dev",
         "open-telemetry/sdk": "1.0.x-dev",
         "open-telemetry/sdk-configuration": "0.1.x-dev",
@@ -59,17 +60,13 @@
         },
         "files": [
             "src/Context/fiber/initialize_fiber_handler.php",
+            "src/API/_register.php",
             "src/API/Trace/functions.php",
+            "src/Config/SDK/_register.php",
             "src/Contrib/Otlp/_register.php",
             "src/Contrib/Grpc/_register.php",
             "src/Contrib/Zipkin/_register.php",
-            "src/Extension/Propagator/B3/_register.php",
-            "src/Extension/Propagator/CloudTrace/_register.php",
-            "src/Extension/Propagator/Jaeger/_register.php",
-            "src/SDK/Logs/Exporter/_register.php",
-            "src/SDK/Metrics/MetricExporter/_register.php",
-            "src/SDK/Propagation/_register.php",
-            "src/SDK/Trace/SpanExporter/_register.php",
+            "src/SDK/_register.php",
             "src/SDK/Common/Dev/Compatibility/_load.php",
             "src/SDK/Common/Util/functions.php",
             "src/SDK/_autoload.php"
@@ -80,7 +77,11 @@
             "OpenTelemetry\\Tests\\": "tests/",
             "OpenTelemetry\\Example\\": "examples/src/",
             "ExampleSDK\\ComponentProvider\\": "tests/Unit/Config/SDK/Configuration/ExampleSdk/"
-        }
+        },
+        "files": [
+            "examples/src/_register.php",
+            "tests/_register.php"
+        ]
     },
     "require-dev": {
         "ext-grpc": "*",
@@ -123,52 +124,18 @@
             "target-directory": "vendor-bin",
             "forward-command": true
         },
-        "spi": {
-            "OpenTelemetry\\Config\\SDK\\Configuration\\ComponentProvider": [
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorB3",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorB3Multi",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorBaggage",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorComposite",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorJaeger",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorTraceContext",
-
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SamplerAlwaysOff",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SamplerAlwaysOn",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SamplerParentBased",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SamplerTraceIdRatioBased",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SpanExporterConsole",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SpanExporterOtlp",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SpanExporterZipkin",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SpanProcessorBatch",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SpanProcessorSimple",
-
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Metrics\\AggregationResolverDefault",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Metrics\\MetricExporterConsole",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Metrics\\MetricExporterOtlp",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Metrics\\MetricReaderPeriodic",
-
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Logs\\LogRecordExporterConsole",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Logs\\LogRecordExporterOtlp",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Logs\\LogRecordProcessorBatch",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Logs\\LogRecordProcessorSimple",
-
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Instrumentation\\General\\HttpConfigProvider",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Instrumentation\\General\\PeerConfigProvider",
-
-                "OpenTelemetry\\Example\\ExampleConfigProvider",
-
-                "OpenTelemetry\\Tests\\Integration\\Config\\ComponentProvider\\Metrics\\AggregationResolverExplicitBucketHistogram",
-                "OpenTelemetry\\Tests\\Integration\\Config\\ComponentProvider\\Metrics\\MetricExporterPrometheus",
-                "OpenTelemetry\\Tests\\Integration\\Config\\ComponentProvider\\Metrics\\MetricReaderPull",
-                "OpenTelemetry\\Tests\\Integration\\Config\\ComponentProvider\\Propagator\\TextMapPropagatorXray",
-                "OpenTelemetry\\Tests\\Integration\\Config\\ComponentProvider\\Propagator\\TextMapPropagatorOtTrace"
-            ],
-            "OpenTelemetry\\API\\Instrumentation\\AutoInstrumentation\\HookManagerInterface": [
-              "OpenTelemetry\\API\\Instrumentation\\AutoInstrumentation\\ExtensionHookManager"
+        "spi-config": {
+            "autoload-files": [
+                "examples/src/_register.php",
+                "src/API/_register.php",
+                "src/Config/SDK/_register.php",
+                "src/Contrib/Otlp/_register.php",
+                "src/Contrib/Grpc/_register.php",
+                "src/Contrib/Zipkin/_register.php",
+                "src/SDK/_register.php",
+                "tests/_register.php"
             ],
-            "OpenTelemetry\\API\\Instrumentation\\AutoInstrumentation\\Instrumentation": [
-                "OpenTelemetry\\Example\\ExampleInstrumentation"
-            ]
+            "prune-autoload-files": true
         }
     }
 }
diff --git a/deptrac.baseline.yaml b/deptrac.baseline.yaml
index cacb15fb7..ebcd48726 100644
--- a/deptrac.baseline.yaml
+++ b/deptrac.baseline.yaml
@@ -1,8 +1,2 @@
 deptrac:
   skip_violations:
-    /src/Extension/Propagator/B3/_register.php:
-      - OpenTelemetry\SDK\Registry
-    /src/Extension/Propagator/CloudTrace/_register.php:
-      - OpenTelemetry\SDK\Registry
-    /src/Extension/Propagator/Jaeger/_register.php:
-      - OpenTelemetry\SDK\Registry
diff --git a/deptrac.yaml b/deptrac.yaml
index 3cca3903c..f32203c5a 100644
--- a/deptrac.yaml
+++ b/deptrac.yaml
@@ -131,6 +131,7 @@ deptrac:
       SDK:
           - +API
           - ConfigSDK
+          - Extension
           - SemConv
           - PsrHttp
           - HttpPlug
diff --git a/docs/upgrading.md b/docs/upgrading.md
new file mode 100644
index 000000000..c25931b2f
--- /dev/null
+++ b/docs/upgrading.md
@@ -0,0 +1,27 @@
+# Upgrading notes for major versions
+
+## 1.x -> 2.x
+
+### SDK
+
+#### SDK\Registry removed
+`SDK\Registry` has been removed, and the technique of registering components (eg propagators, transports,
+auto-instrumentations) has been replaced with [Nevay/SPI](https://github.com/Nevay/spi/) ServiceLoader.
+
+The ServiceLoader should be configured through existing `_register.php` files, which should *only* contain calls to
+SPI's `ServiceLoader::register()` method.
+
+SPI has a composer plugin which will scan for `ServiceLoader::register()` calls in `autoload.files` and generate a
+`GeneratedServiceProviderData.php` file in `vendor/composer/`. The plugin will then remove those `autoload.files` entries
+from composer's generated output to avoid double-loading.
+Pre-generating the services in this way avoids a race-condition in 1.x where composer's `autoload.files` are executed in an
+undefined order, and services may not be registered in time for the SDK to use them.
+
+For SPI to work correctly, the composer plugin _should_ be allowed to run. If the plugin is not allowed to run, then
+services will still register at runtime, however this might still suffer from the same race-condition as `1.x`.
+
+#### FactoryInterfaces updated
+Various component factory interfaces (eg `TextMapPropagatorFactoryInterface`, `TransportFactoryInterface`) have been
+updated to include `priority()` and `type()` methods. These are used in conjunction with SPI ServiceLoader to associate
+a type (eg `otlp`) with a factory, and to allow SDK-provided factories to be replaced by user-provided factories (by
+providing a higher priority for the same type).
diff --git a/examples/autoload_sdk_with_custom_transport.php b/examples/autoload_sdk_with_custom_transport.php
index 28d742caf..e53969f33 100644
--- a/examples/autoload_sdk_with_custom_transport.php
+++ b/examples/autoload_sdk_with_custom_transport.php
@@ -4,6 +4,9 @@
 
 namespace OpenTelemetry\Example;
 
+use Nevay\SPI\ServiceLoader;
+use OpenTelemetry\SDK\Common\Export\TransportFactoryInterface;
+
 putenv('OTEL_PHP_AUTOLOAD_ENABLED=true');
 putenv('OTEL_TRACES_EXPORTER=otlp');
 putenv('OTEL_EXPORTER_OTLP_PROTOCOL=grpc');
@@ -45,9 +48,19 @@ public function forceFlush(?\OpenTelemetry\SDK\Common\Future\CancellationInterfa
             }
         };
     }
+
+    public function type(): string
+    {
+        return 'grpc';
+    }
+
+    public function priority(): int
+    {
+        return 100;
+    }
 };
 
-\OpenTelemetry\SDK\Registry::registerTransportFactory('grpc', $factory, true);
+ServiceLoader::register(TransportFactoryInterface::class, $factory::class);
 
 $instrumentation = new \OpenTelemetry\API\Instrumentation\CachedInstrumentation('demo');
 
diff --git a/examples/logs/exporters/otlp_http.php b/examples/logs/exporters/otlp_http.php
index 27af3a6ca..870b967d5 100644
--- a/examples/logs/exporters/otlp_http.php
+++ b/examples/logs/exporters/otlp_http.php
@@ -7,7 +7,7 @@
 use OpenTelemetry\API\Logs\LogRecord;
 use OpenTelemetry\API\Logs\Severity;
 use OpenTelemetry\Contrib\Otlp\LogsExporter;
-use OpenTelemetry\Contrib\Otlp\OtlpHttpTransportFactory;
+use OpenTelemetry\SDK\Common\Export\Http\PsrTransportFactory;
 use OpenTelemetry\SDK\Common\Instrumentation\InstrumentationScopeFactory;
 use OpenTelemetry\SDK\Logs\EventLoggerProvider;
 use OpenTelemetry\SDK\Logs\LoggerProvider;
@@ -16,7 +16,7 @@
 
 require __DIR__ . '/../../../vendor/autoload.php';
 
-$transport = (new OtlpHttpTransportFactory())->create('http://collector:4318/v1/logs', 'application/json');
+$transport = (new PsrTransportFactory())->create('http://collector:4318/v1/logs', 'application/json');
 $exporter = new LogsExporter($transport);
 
 $loggerProvider = new LoggerProvider(
diff --git a/examples/src/ExampleConfig.php b/examples/src/ExampleConfig.php
index e2385bd4f..8afba601d 100644
--- a/examples/src/ExampleConfig.php
+++ b/examples/src/ExampleConfig.php
@@ -13,4 +13,9 @@ public function __construct(
         public readonly bool $enabled = true,
     ) {
     }
+
+    public static function default(): self
+    {
+        return new self('example');
+    }
 }
diff --git a/examples/src/ExampleInstrumentation.php b/examples/src/ExampleInstrumentation.php
index d1ccf73a3..bef052547 100644
--- a/examples/src/ExampleInstrumentation.php
+++ b/examples/src/ExampleInstrumentation.php
@@ -4,7 +4,6 @@
 
 namespace OpenTelemetry\Example;
 
-use Exception;
 use OpenTelemetry\API\Configuration\ConfigProperties;
 use OpenTelemetry\API\Instrumentation\AutoInstrumentation\Context as InstrumentationContext;
 use OpenTelemetry\API\Instrumentation\AutoInstrumentation\HookManagerInterface;
@@ -16,7 +15,7 @@ final class ExampleInstrumentation implements Instrumentation
 {
     public function register(HookManagerInterface $hookManager, ConfigProperties $configuration, InstrumentationContext $context): void
     {
-        $config = $configuration->get(ExampleConfig::class) ?? throw new Exception('example instrumentation must be configured');
+        $config = $configuration->get(ExampleConfig::class) ?? ExampleConfig::default();
         if (!$config->enabled) {
             return;
         }
diff --git a/examples/src/TestResourceDetector.php b/examples/src/TestResourceDetector.php
new file mode 100644
index 000000000..3dbf1ee3a
--- /dev/null
+++ b/examples/src/TestResourceDetector.php
@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\Example;
+
+use OpenTelemetry\SDK\Common\Attribute\Attributes;
+use OpenTelemetry\SDK\Resource\ResourceDetectorInterface;
+use OpenTelemetry\SDK\Resource\ResourceInfo;
+use OpenTelemetry\SemConv\ResourceAttributes;
+
+class TestResourceDetector implements ResourceDetectorInterface
+{
+    public function getResource(): ResourceInfo
+    {
+        $attributes = [
+            'test-resource' => 'test-value',
+        ];
+
+        return ResourceInfo::create(Attributes::create($attributes), ResourceAttributes::SCHEMA_URL);
+    }
+}
diff --git a/examples/src/TestResourceDetectorFactory.php b/examples/src/TestResourceDetectorFactory.php
new file mode 100644
index 000000000..f1bac2d30
--- /dev/null
+++ b/examples/src/TestResourceDetectorFactory.php
@@ -0,0 +1,26 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\Example;
+
+use OpenTelemetry\SDK\Resource\ResourceDetectorFactoryInterface;
+use OpenTelemetry\SDK\Resource\ResourceDetectorInterface;
+
+class TestResourceDetectorFactory implements ResourceDetectorFactoryInterface
+{
+    public function create(): ResourceDetectorInterface
+    {
+        return new TestResourceDetector();
+    }
+
+    public function type(): string
+    {
+        return 'test';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+}
diff --git a/examples/src/_register.php b/examples/src/_register.php
new file mode 100644
index 000000000..8bcebd4af
--- /dev/null
+++ b/examples/src/_register.php
@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+use Nevay\SPI\ServiceLoader;
+use OpenTelemetry\API\Instrumentation\AutoInstrumentation\Instrumentation;
+use OpenTelemetry\Config\SDK\Configuration\ComponentProvider;
+use OpenTelemetry\Example\ExampleConfigProvider;
+use OpenTelemetry\Example\ExampleInstrumentation;
+use OpenTelemetry\Example\TestResourceDetectorFactory;
+use OpenTelemetry\SDK\Resource\ResourceDetectorFactoryInterface;
+
+ServiceLoader::register(Instrumentation::class, ExampleInstrumentation::class);
+ServiceLoader::register(ResourceDetectorFactoryInterface::class, TestResourceDetectorFactory::class);
+ServiceLoader::register(ComponentProvider::class, ExampleConfigProvider::class);
diff --git a/examples/traces/exporters/otlp_http.php b/examples/traces/exporters/otlp_http.php
index 19d5cb678..f6d988e8e 100644
--- a/examples/traces/exporters/otlp_http.php
+++ b/examples/traces/exporters/otlp_http.php
@@ -6,12 +6,12 @@
 
 require __DIR__ . '/../../../vendor/autoload.php';
 
-use OpenTelemetry\Contrib\Otlp\OtlpHttpTransportFactory;
 use OpenTelemetry\Contrib\Otlp\SpanExporter;
+use OpenTelemetry\SDK\Common\Export\Http\PsrTransportFactory;
 use OpenTelemetry\SDK\Trace\SpanProcessor\SimpleSpanProcessor;
 use OpenTelemetry\SDK\Trace\TracerProvider;
 
-$transport = (new OtlpHttpTransportFactory())->create('http://collector:4318/v1/traces', 'application/x-protobuf');
+$transport = (new PsrTransportFactory())->create('http://collector:4318/v1/traces', 'application/x-protobuf');
 $exporter = new SpanExporter($transport);
 
 echo 'Starting OTLP example';
diff --git a/examples/traces/exporters/otlp_http_json.php b/examples/traces/exporters/otlp_http_json.php
index c89c267a6..e33bb78eb 100644
--- a/examples/traces/exporters/otlp_http_json.php
+++ b/examples/traces/exporters/otlp_http_json.php
@@ -7,12 +7,12 @@
 require __DIR__ . '/../../../vendor/autoload.php';
 
 use OpenTelemetry\Contrib\Otlp\ContentTypes;
-use OpenTelemetry\Contrib\Otlp\OtlpHttpTransportFactory;
 use OpenTelemetry\Contrib\Otlp\SpanExporter;
+use OpenTelemetry\SDK\Common\Export\Http\PsrTransportFactory;
 use OpenTelemetry\SDK\Trace\SpanProcessor\SimpleSpanProcessor;
 use OpenTelemetry\SDK\Trace\TracerProvider;
 
-$transport = (new OtlpHttpTransportFactory())->create('http://collector:4318/v1/traces', ContentTypes::JSON);
+$transport = (new PsrTransportFactory())->create('http://collector:4318/v1/traces', ContentTypes::JSON);
 $exporter = new SpanExporter($transport);
 
 echo 'Starting OTLP+json example';
diff --git a/examples/traces/features/auto_root_span.php b/examples/traces/features/auto_root_span.php
index 5ac62379b..3051a2636 100644
--- a/examples/traces/features/auto_root_span.php
+++ b/examples/traces/features/auto_root_span.php
@@ -11,8 +11,11 @@
 putenv('OTEL_TRACES_EXPORTER=console');
 putenv('OTEL_METRICS_EXPORTER=none');
 putenv('OTEL_LOGS_EXPORTER=console');
+putenv('OTEL_EXPORTER_OTLP_ENDPOINT=http://collector:4318');
+putenv('OTEL_EXPORTER_OTLP_PROTOCOL=http/protobuf');
 putenv('OTEL_PROPAGATORS=tracecontext');
 putenv('OTEL_PHP_EXPERIMENTAL_AUTO_ROOT_SPAN=true');
+putenv('OTEL_PHP_DETECTORS=sdk,test');
 
 //Usage: php -S localhost:8080 examples/traces/features/auto_root_span.php
 
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index 807247557..da5316b39 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -50,4 +50,4 @@ parameters:
         -
             message: "#.*return with type T is not subtype.*#"
             paths:
-                - src/SDK/Common/InstrumentationScope
\ No newline at end of file
+                - src/SDK/Common/InstrumentationScope
diff --git a/src/API/_register.php b/src/API/_register.php
new file mode 100644
index 000000000..aefc26f03
--- /dev/null
+++ b/src/API/_register.php
@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+use Nevay\SPI\ServiceLoader;
+use OpenTelemetry\API\Instrumentation\AutoInstrumentation\ExtensionHookManager;
+use OpenTelemetry\API\Instrumentation\AutoInstrumentation\HookManagerInterface;
+
+ServiceLoader::register(HookManagerInterface::class, ExtensionHookManager::class);
diff --git a/src/API/composer.json b/src/API/composer.json
index 6cd29f6fa..ea66d5f05 100644
--- a/src/API/composer.json
+++ b/src/API/composer.json
@@ -19,7 +19,8 @@
     "require": {
         "php": "^8.2",
         "open-telemetry/context": "^1.0|^2.0",
-        "psr/log": "^1.1|^2.0|^3.0"
+        "psr/log": "^1.1|^2.0|^3.0",
+        "tbachert/spi": "^1.0.1"
     },
     "conflict": {
         "open-telemetry/sdk": "<=1.0.8"
@@ -29,6 +30,7 @@
             "OpenTelemetry\\API\\": "."
         },
         "files": [
+            "_register.php",
             "Trace/functions.php"
         ]
     },
@@ -37,10 +39,11 @@
             "dev-main": "1.1.x-dev",
             "dev-2.x": "2.x-dev"
         },
-        "spi": {
-            "OpenTelemetry\\API\\Instrumentation\\AutoInstrumentation\\HookManagerInterface": [
-                "OpenTelemetry\\API\\Instrumentation\\AutoInstrumentation\\ExtensionHookManager"
-            ]
+        "spi-config": {
+            "autoload-files": [
+                "_register.php"
+            ],
+            "prune-autoload-files": true
         }
     }
 }
diff --git a/src/Config/SDK/ComponentProvider/Logs/LogRecordExporterConsole.php b/src/Config/SDK/ComponentProvider/Logs/LogRecordExporterConsole.php
index 2341cd95b..4d16875e2 100644
--- a/src/Config/SDK/ComponentProvider/Logs/LogRecordExporterConsole.php
+++ b/src/Config/SDK/ComponentProvider/Logs/LogRecordExporterConsole.php
@@ -7,9 +7,9 @@
 use OpenTelemetry\Config\SDK\Configuration\ComponentProvider;
 use OpenTelemetry\Config\SDK\Configuration\ComponentProviderRegistry;
 use OpenTelemetry\Config\SDK\Configuration\Context;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Logs\Exporter\ConsoleExporter;
 use OpenTelemetry\SDK\Logs\LogRecordExporterInterface;
-use OpenTelemetry\SDK\Registry;
 use Symfony\Component\Config\Definition\Builder\ArrayNodeDefinition;
 use Symfony\Component\Config\Definition\Builder\NodeBuilder;
 
@@ -23,7 +23,7 @@ final class LogRecordExporterConsole implements ComponentProvider
      */
     public function createPlugin(array $properties, Context $context): LogRecordExporterInterface
     {
-        return new ConsoleExporter(Registry::transportFactory('stream')->create(
+        return new ConsoleExporter(Loader::transportFactory('stream')->create(
             endpoint: 'php://stdout',
             contentType: 'application/json',
         ));
diff --git a/src/Config/SDK/ComponentProvider/Logs/LogRecordExporterOtlp.php b/src/Config/SDK/ComponentProvider/Logs/LogRecordExporterOtlp.php
index e580e7782..baec95070 100644
--- a/src/Config/SDK/ComponentProvider/Logs/LogRecordExporterOtlp.php
+++ b/src/Config/SDK/ComponentProvider/Logs/LogRecordExporterOtlp.php
@@ -14,8 +14,8 @@
 use OpenTelemetry\Contrib\Otlp\OtlpUtil;
 use OpenTelemetry\Contrib\Otlp\Protocols;
 use OpenTelemetry\SDK\Common\Configuration\Parser\MapParser;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Logs\LogRecordExporterInterface;
-use OpenTelemetry\SDK\Registry;
 use Symfony\Component\Config\Definition\Builder\ArrayNodeDefinition;
 use Symfony\Component\Config\Definition\Builder\NodeBuilder;
 
@@ -45,7 +45,7 @@ public function createPlugin(array $properties, Context $context): LogRecordExpo
 
         $headers = array_column($properties['headers'], 'value', 'name') + MapParser::parse($properties['headers_list']);
 
-        return new LogsExporter(Registry::transportFactory($protocol)->create(
+        return new LogsExporter(Loader::transportFactory($protocol)->create(
             endpoint: $properties['endpoint'] . OtlpUtil::path(Signals::LOGS, $protocol),
             contentType: Protocols::contentType($protocol),
             headers: $headers,
diff --git a/src/Config/SDK/ComponentProvider/Metrics/MetricExporterOtlp.php b/src/Config/SDK/ComponentProvider/Metrics/MetricExporterOtlp.php
index f92872b49..ce0855898 100644
--- a/src/Config/SDK/ComponentProvider/Metrics/MetricExporterOtlp.php
+++ b/src/Config/SDK/ComponentProvider/Metrics/MetricExporterOtlp.php
@@ -14,9 +14,9 @@
 use OpenTelemetry\Contrib\Otlp\OtlpUtil;
 use OpenTelemetry\Contrib\Otlp\Protocols;
 use OpenTelemetry\SDK\Common\Configuration\Parser\MapParser;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Metrics\Data\Temporality;
 use OpenTelemetry\SDK\Metrics\MetricExporterInterface;
-use OpenTelemetry\SDK\Registry;
 use Symfony\Component\Config\Definition\Builder\ArrayNodeDefinition;
 use Symfony\Component\Config\Definition\Builder\NodeBuilder;
 
@@ -54,7 +54,7 @@ public function createPlugin(array $properties, Context $context): MetricExporte
             'lowmemory' => null,
         };
 
-        return new MetricExporter(Registry::transportFactory($protocol)->create(
+        return new MetricExporter(Loader::transportFactory($protocol)->create(
             endpoint: $properties['endpoint'] . OtlpUtil::path(Signals::METRICS, $protocol),
             contentType: Protocols::contentType($protocol),
             headers: $headers,
diff --git a/src/Config/SDK/ComponentProvider/Propagator/TextMapPropagatorCloudTrace.php b/src/Config/SDK/ComponentProvider/Propagator/TextMapPropagatorCloudTrace.php
new file mode 100644
index 000000000..5e69b10f3
--- /dev/null
+++ b/src/Config/SDK/ComponentProvider/Propagator/TextMapPropagatorCloudTrace.php
@@ -0,0 +1,34 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\Config\SDK\ComponentProvider\Propagator;
+
+use Nevay\SPI\ServiceProviderDependency\PackageDependency;
+use OpenTelemetry\Config\SDK\Configuration\ComponentProvider;
+use OpenTelemetry\Config\SDK\Configuration\ComponentProviderRegistry;
+use OpenTelemetry\Config\SDK\Configuration\Context;
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\Extension\Propagator\CloudTrace\CloudTracePropagator;
+use Symfony\Component\Config\Definition\Builder\ArrayNodeDefinition;
+use Symfony\Component\Config\Definition\Builder\NodeBuilder;
+
+/**
+ * @implements ComponentProvider<TextMapPropagatorInterface>
+ */
+#[PackageDependency('open-telemetry/extension-propagator-cloudtrace', '^0.0.4')]
+final class TextMapPropagatorCloudTrace implements ComponentProvider
+{
+    /**
+     * @param array{} $properties
+     */
+    public function createPlugin(array $properties, Context $context): TextMapPropagatorInterface
+    {
+        return CloudTracePropagator::getInstance();
+    }
+
+    public function getConfig(ComponentProviderRegistry $registry, NodeBuilder $builder): ArrayNodeDefinition
+    {
+        return $builder->arrayNode('cloudtrace');
+    }
+}
diff --git a/src/Config/SDK/ComponentProvider/Propagator/TextMapPropagatorJaeger.php b/src/Config/SDK/ComponentProvider/Propagator/TextMapPropagatorJaeger.php
index 39eed7948..d17be129a 100644
--- a/src/Config/SDK/ComponentProvider/Propagator/TextMapPropagatorJaeger.php
+++ b/src/Config/SDK/ComponentProvider/Propagator/TextMapPropagatorJaeger.php
@@ -16,7 +16,7 @@
 /**
  * @implements ComponentProvider<TextMapPropagatorInterface>
  */
-#[PackageDependency('open-telemetry/extension-propagator-jaeger', '^0.0.2')]
+#[PackageDependency('open-telemetry/extension-propagator-jaeger', '^0.0.3')]
 final class TextMapPropagatorJaeger implements ComponentProvider
 {
     /**
diff --git a/src/Config/SDK/ComponentProvider/Trace/SpanExporterConsole.php b/src/Config/SDK/ComponentProvider/Trace/SpanExporterConsole.php
index 6596b014d..e9fdc006b 100644
--- a/src/Config/SDK/ComponentProvider/Trace/SpanExporterConsole.php
+++ b/src/Config/SDK/ComponentProvider/Trace/SpanExporterConsole.php
@@ -7,7 +7,7 @@
 use OpenTelemetry\Config\SDK\Configuration\ComponentProvider;
 use OpenTelemetry\Config\SDK\Configuration\ComponentProviderRegistry;
 use OpenTelemetry\Config\SDK\Configuration\Context;
-use OpenTelemetry\SDK\Registry;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Trace\SpanExporter\ConsoleSpanExporter;
 use OpenTelemetry\SDK\Trace\SpanExporterInterface;
 use Symfony\Component\Config\Definition\Builder\ArrayNodeDefinition;
@@ -23,7 +23,7 @@ final class SpanExporterConsole implements ComponentProvider
      */
     public function createPlugin(array $properties, Context $context): SpanExporterInterface
     {
-        return new ConsoleSpanExporter(Registry::transportFactory('stream')->create(
+        return new ConsoleSpanExporter(Loader::transportFactory('stream')->create(
             endpoint: 'php://stdout',
             contentType: 'application/json',
         ));
diff --git a/src/Config/SDK/ComponentProvider/Trace/SpanExporterOtlp.php b/src/Config/SDK/ComponentProvider/Trace/SpanExporterOtlp.php
index 83140c5fd..e94247d15 100644
--- a/src/Config/SDK/ComponentProvider/Trace/SpanExporterOtlp.php
+++ b/src/Config/SDK/ComponentProvider/Trace/SpanExporterOtlp.php
@@ -14,7 +14,7 @@
 use OpenTelemetry\Contrib\Otlp\Protocols;
 use OpenTelemetry\Contrib\Otlp\SpanExporter;
 use OpenTelemetry\SDK\Common\Configuration\Parser\MapParser;
-use OpenTelemetry\SDK\Registry;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Trace\SpanExporterInterface;
 use Symfony\Component\Config\Definition\Builder\ArrayNodeDefinition;
 use Symfony\Component\Config\Definition\Builder\NodeBuilder;
@@ -45,7 +45,7 @@ public function createPlugin(array $properties, Context $context): SpanExporterI
 
         $headers = array_column($properties['headers'], 'value', 'name') + MapParser::parse($properties['headers_list']);
 
-        return new SpanExporter(Registry::transportFactory($protocol)->create(
+        return new SpanExporter(Loader::transportFactory($protocol)->create(
             endpoint: $properties['endpoint'] . OtlpUtil::path(Signals::TRACE, $protocol),
             contentType: Protocols::contentType($protocol),
             headers: $headers,
diff --git a/src/Config/SDK/ComponentProvider/Trace/SpanExporterZipkin.php b/src/Config/SDK/ComponentProvider/Trace/SpanExporterZipkin.php
index 4451ef151..936a5efee 100644
--- a/src/Config/SDK/ComponentProvider/Trace/SpanExporterZipkin.php
+++ b/src/Config/SDK/ComponentProvider/Trace/SpanExporterZipkin.php
@@ -10,7 +10,7 @@
 use OpenTelemetry\Config\SDK\Configuration\Context;
 use OpenTelemetry\Config\SDK\Configuration\Validation;
 use OpenTelemetry\Contrib\Zipkin;
-use OpenTelemetry\SDK\Registry;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Trace\SpanExporterInterface;
 use Symfony\Component\Config\Definition\Builder\ArrayNodeDefinition;
 use Symfony\Component\Config\Definition\Builder\NodeBuilder;
@@ -29,7 +29,7 @@ final class SpanExporterZipkin implements ComponentProvider
      */
     public function createPlugin(array $properties, Context $context): SpanExporterInterface
     {
-        return new Zipkin\Exporter(Registry::transportFactory('http')->create(
+        return new Zipkin\Exporter(Loader::transportFactory('http')->create(
             endpoint: $properties['endpoint'],
             contentType: 'application/json',
             timeout: $properties['timeout'],
diff --git a/src/Config/SDK/_register.php b/src/Config/SDK/_register.php
new file mode 100644
index 000000000..a2201f5cb
--- /dev/null
+++ b/src/Config/SDK/_register.php
@@ -0,0 +1,64 @@
+<?php
+
+declare(strict_types=1);
+
+use Nevay\SPI\ServiceLoader;
+use OpenTelemetry\Config\SDK\ComponentProvider\Instrumentation\General\HttpConfigProvider;
+use OpenTelemetry\Config\SDK\ComponentProvider\Instrumentation\General\PeerConfigProvider;
+use OpenTelemetry\Config\SDK\ComponentProvider\Logs\LogRecordExporterConsole;
+use OpenTelemetry\Config\SDK\ComponentProvider\Logs\LogRecordExporterOtlp;
+use OpenTelemetry\Config\SDK\ComponentProvider\Logs\LogRecordProcessorBatch;
+use OpenTelemetry\Config\SDK\ComponentProvider\Logs\LogRecordProcessorSimple;
+use OpenTelemetry\Config\SDK\ComponentProvider\Metrics\AggregationResolverDefault;
+use OpenTelemetry\Config\SDK\ComponentProvider\Metrics\MetricExporterConsole;
+use OpenTelemetry\Config\SDK\ComponentProvider\Metrics\MetricExporterOtlp;
+use OpenTelemetry\Config\SDK\ComponentProvider\Metrics\MetricReaderPeriodic;
+use OpenTelemetry\Config\SDK\ComponentProvider\Propagator\TextMapPropagatorB3;
+use OpenTelemetry\Config\SDK\ComponentProvider\Propagator\TextMapPropagatorB3Multi;
+use OpenTelemetry\Config\SDK\ComponentProvider\Propagator\TextMapPropagatorBaggage;
+use OpenTelemetry\Config\SDK\ComponentProvider\Propagator\TextMapPropagatorCloudTrace;
+use OpenTelemetry\Config\SDK\ComponentProvider\Propagator\TextMapPropagatorComposite;
+use OpenTelemetry\Config\SDK\ComponentProvider\Propagator\TextMapPropagatorJaeger;
+use OpenTelemetry\Config\SDK\ComponentProvider\Propagator\TextMapPropagatorTraceContext;
+use OpenTelemetry\Config\SDK\ComponentProvider\Trace\SamplerAlwaysOff;
+use OpenTelemetry\Config\SDK\ComponentProvider\Trace\SamplerAlwaysOn;
+use OpenTelemetry\Config\SDK\ComponentProvider\Trace\SamplerParentBased;
+use OpenTelemetry\Config\SDK\ComponentProvider\Trace\SamplerTraceIdRatioBased;
+use OpenTelemetry\Config\SDK\ComponentProvider\Trace\SpanExporterConsole;
+use OpenTelemetry\Config\SDK\ComponentProvider\Trace\SpanExporterOtlp;
+use OpenTelemetry\Config\SDK\ComponentProvider\Trace\SpanExporterZipkin;
+use OpenTelemetry\Config\SDK\ComponentProvider\Trace\SpanProcessorBatch;
+use OpenTelemetry\Config\SDK\ComponentProvider\Trace\SpanProcessorSimple;
+use OpenTelemetry\Config\SDK\Configuration\ComponentProvider;
+
+ServiceLoader::register(ComponentProvider::class, TextMapPropagatorB3::class);
+ServiceLoader::register(ComponentProvider::class, TextMapPropagatorB3Multi::class);
+ServiceLoader::register(ComponentProvider::class, TextMapPropagatorBaggage::class);
+ServiceLoader::register(ComponentProvider::class, TextMapPropagatorComposite::class);
+ServiceLoader::register(ComponentProvider::class, TextMapPropagatorCloudTrace::class);
+ServiceLoader::register(ComponentProvider::class, TextMapPropagatorJaeger::class);
+ServiceLoader::register(ComponentProvider::class, TextMapPropagatorTraceContext::class);
+
+ServiceLoader::register(ComponentProvider::class, SamplerAlwaysOff::class);
+ServiceLoader::register(ComponentProvider::class, SamplerAlwaysOn::class);
+ServiceLoader::register(ComponentProvider::class, SamplerParentBased::class);
+ServiceLoader::register(ComponentProvider::class, SamplerTraceIdRatioBased::class);
+
+ServiceLoader::register(ComponentProvider::class, SpanExporterConsole::class);
+ServiceLoader::register(ComponentProvider::class, SpanExporterOtlp::class);
+ServiceLoader::register(ComponentProvider::class, SpanExporterZipkin::class);
+ServiceLoader::register(ComponentProvider::class, SpanProcessorBatch::class);
+ServiceLoader::register(ComponentProvider::class, SpanProcessorSimple::class);
+
+ServiceLoader::register(ComponentProvider::class, AggregationResolverDefault::class);
+ServiceLoader::register(ComponentProvider::class, MetricExporterConsole::class);
+ServiceLoader::register(ComponentProvider::class, MetricExporterOtlp::class);
+ServiceLoader::register(ComponentProvider::class, MetricReaderPeriodic::class);
+
+ServiceLoader::register(ComponentProvider::class, LogRecordExporterConsole::class);
+ServiceLoader::register(ComponentProvider::class, LogRecordExporterOtlp::class);
+ServiceLoader::register(ComponentProvider::class, LogRecordProcessorBatch::class);
+ServiceLoader::register(ComponentProvider::class, LogRecordProcessorSimple::class);
+
+ServiceLoader::register(ComponentProvider::class, HttpConfigProvider::class);
+ServiceLoader::register(ComponentProvider::class, PeerConfigProvider::class);
diff --git a/src/Config/SDK/composer.json b/src/Config/SDK/composer.json
index 5b55dd969..58b80d8a9 100644
--- a/src/Config/SDK/composer.json
+++ b/src/Config/SDK/composer.json
@@ -24,6 +24,9 @@
         "tbachert/spi": "^1.0.1"
     },
     "autoload": {
+        "files": [
+            "_register.php"
+        ],
         "psr-4": {
             "OpenTelemetry\\Config\\SDK\\": ""
         }
@@ -38,38 +41,9 @@
             "dev-main": "0.1.x-dev",
             "dev-2.x": "2.x-dev"
         },
-        "spi": {
-            "OpenTelemetry\\Config\\SDK\\Configuration\\ComponentProvider": [
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorB3",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorB3Multi",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorBaggage",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorComposite",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorJaeger",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Propagator\\TextMapPropagatorTraceContext",
-
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SamplerAlwaysOff",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SamplerAlwaysOn",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SamplerParentBased",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SamplerTraceIdRatioBased",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SpanExporterConsole",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SpanExporterOtlp",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SpanExporterZipkin",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SpanProcessorBatch",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Trace\\SpanProcessorSimple",
-
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Metrics\\AggregationResolverDefault",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Metrics\\MetricExporterConsole",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Metrics\\MetricExporterOtlp",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Metrics\\MetricReaderPeriodic",
-
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Logs\\LogRecordExporterConsole",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Logs\\LogRecordExporterOtlp",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Logs\\LogRecordProcessorBatch",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Logs\\LogRecordProcessorSimple",
-
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Instrumentation\\General\\HttpConfigProvider",
-                "OpenTelemetry\\Config\\SDK\\ComponentProvider\\Instrumentation\\General\\PeerConfigProvider"
-            ]
+        "spi-config": {
+            "autoload-files": true,
+            "prune-autoload-files": true
         }
     }
 }
diff --git a/src/Contrib/Grpc/GrpcTransportFactory.php b/src/Contrib/Grpc/GrpcTransportFactory.php
index 246b0cacb..4774acf9d 100644
--- a/src/Contrib/Grpc/GrpcTransportFactory.php
+++ b/src/Contrib/Grpc/GrpcTransportFactory.php
@@ -157,4 +157,14 @@ private static function fileGetContents(?string $file): ?string
 
         return $content;
     }
+
+    public function type(): string
+    {
+        return 'grpc';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/Contrib/Grpc/_register.php b/src/Contrib/Grpc/_register.php
index 94883eebf..127e69fd4 100644
--- a/src/Contrib/Grpc/_register.php
+++ b/src/Contrib/Grpc/_register.php
@@ -1,4 +1,9 @@
 <?php
 
 declare(strict_types=1);
-\OpenTelemetry\SDK\Registry::registerTransportFactory('grpc', \OpenTelemetry\Contrib\Grpc\GrpcTransportFactory::class);
+
+use Nevay\SPI\ServiceLoader;
+use OpenTelemetry\Contrib\Grpc\GrpcTransportFactory;
+use OpenTelemetry\SDK\Common\Export\TransportFactoryInterface;
+
+ServiceLoader::register(TransportFactoryInterface::class, GrpcTransportFactory::class);
diff --git a/src/Contrib/Grpc/composer.json b/src/Contrib/Grpc/composer.json
index f9034533e..4888bb6c1 100644
--- a/src/Contrib/Grpc/composer.json
+++ b/src/Contrib/Grpc/composer.json
@@ -21,7 +21,8 @@
     "ext-grpc": "*",
     "grpc/grpc": "*",
     "open-telemetry/sdk": "^1.0|^2.0",
-    "open-telemetry/exporter-otlp": "^1.0|^2.0"
+    "open-telemetry/exporter-otlp": "^1.0|^2.0",
+    "tbachert/spi": "^1.0.1"
   },
   "autoload": {
     "psr-4": {
@@ -32,6 +33,10 @@
     ]
   },
   "extra": {
+    "spi-config": {
+      "autoload-files": true,
+      "prune-autoload-files": true
+    },
     "branch-alias": {
       "dev-main": "1.0.x-dev",
       "dev-2.x": "2.x-dev"
diff --git a/src/Contrib/Otlp/LogsExporterFactory.php b/src/Contrib/Otlp/LogsExporterFactory.php
index a92cffa3b..32d7489b8 100644
--- a/src/Contrib/Otlp/LogsExporterFactory.php
+++ b/src/Contrib/Otlp/LogsExporterFactory.php
@@ -10,9 +10,9 @@
 use OpenTelemetry\SDK\Common\Configuration\Variables;
 use OpenTelemetry\SDK\Common\Export\TransportFactoryInterface;
 use OpenTelemetry\SDK\Common\Export\TransportInterface;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Logs\LogRecordExporterFactoryInterface;
 use OpenTelemetry\SDK\Logs\LogRecordExporterInterface;
-use OpenTelemetry\SDK\Registry;
 
 class LogsExporterFactory implements LogRecordExporterFactoryInterface
 {
@@ -34,6 +34,16 @@ public function create(): LogRecordExporterInterface
         return new LogsExporter($this->buildTransport($protocol));
     }
 
+    public function type(): string
+    {
+        return 'otlp';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+
     /**
      * @psalm-suppress UndefinedClass
      */
@@ -45,8 +55,7 @@ private function buildTransport(string $protocol): TransportInterface
         $compression = $this->getCompression();
         $timeout = $this->getTimeout();
 
-        $factoryClass = Registry::transportFactory($protocol);
-        $factory = $this->transportFactory ?: new $factoryClass();
+        $factory = $this->transportFactory ?? Loader::transportFactory($protocol);
 
         return $factory->create(
             $endpoint,
diff --git a/src/Contrib/Otlp/MetricExporterFactory.php b/src/Contrib/Otlp/MetricExporterFactory.php
index 1ba7488f3..7bd9d28c7 100644
--- a/src/Contrib/Otlp/MetricExporterFactory.php
+++ b/src/Contrib/Otlp/MetricExporterFactory.php
@@ -10,10 +10,10 @@
 use OpenTelemetry\SDK\Common\Configuration\Variables;
 use OpenTelemetry\SDK\Common\Export\TransportFactoryInterface;
 use OpenTelemetry\SDK\Common\Export\TransportInterface;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Metrics\Data\Temporality;
 use OpenTelemetry\SDK\Metrics\MetricExporterFactoryInterface;
 use OpenTelemetry\SDK\Metrics\MetricExporterInterface;
-use OpenTelemetry\SDK\Registry;
 
 class MetricExporterFactory implements MetricExporterFactoryInterface
 {
@@ -36,6 +36,16 @@ public function create(): MetricExporterInterface
         return new MetricExporter($this->buildTransport($protocol), $temporality);
     }
 
+    public function type(): string
+    {
+        return 'otlp';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+
     /**
      * @psalm-suppress UndefinedClass
      */
@@ -51,8 +61,7 @@ private function buildTransport(string $protocol): TransportInterface
         $compression = $this->getCompression();
         $timeout = $this->getTimeout();
 
-        $factoryClass = Registry::transportFactory($protocol);
-        $factory = $this->transportFactory ?: new $factoryClass();
+        $factory = $this->transportFactory ?? Loader::transportFactory($protocol);
 
         return $factory->create(
             $endpoint,
diff --git a/src/Contrib/Otlp/OtlpHttpTransportFactory.php b/src/Contrib/Otlp/OtlpHttpTransportFactory.php
deleted file mode 100644
index f40af681a..000000000
--- a/src/Contrib/Otlp/OtlpHttpTransportFactory.php
+++ /dev/null
@@ -1,34 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace OpenTelemetry\Contrib\Otlp;
-
-use OpenTelemetry\SDK\Common\Export\Http\PsrTransport;
-use OpenTelemetry\SDK\Common\Export\Http\PsrTransportFactory;
-use OpenTelemetry\SDK\Common\Export\TransportFactoryInterface;
-
-class OtlpHttpTransportFactory implements TransportFactoryInterface
-{
-    private const DEFAULT_COMPRESSION = 'none';
-
-    public function create(
-        string $endpoint,
-        string $contentType,
-        array $headers = [],
-        $compression = null,
-        float $timeout = 10.,
-        int $retryDelay = 100,
-        int $maxRetries = 3,
-        ?string $cacert = null,
-        ?string $cert = null,
-        ?string $key = null,
-    ): PsrTransport {
-        if ($compression === self::DEFAULT_COMPRESSION) {
-            $compression = null;
-        }
-
-        return (new PsrTransportFactory())
-            ->create($endpoint, $contentType, $headers, $compression, $timeout, $retryDelay, $maxRetries, $cacert, $cert, $key);
-    }
-}
diff --git a/src/Contrib/Otlp/SpanExporterFactory.php b/src/Contrib/Otlp/SpanExporterFactory.php
index 1ef7d49aa..ac77c3ec4 100644
--- a/src/Contrib/Otlp/SpanExporterFactory.php
+++ b/src/Contrib/Otlp/SpanExporterFactory.php
@@ -11,7 +11,7 @@
 use OpenTelemetry\SDK\Common\Configuration\Variables;
 use OpenTelemetry\SDK\Common\Export\TransportFactoryInterface;
 use OpenTelemetry\SDK\Common\Export\TransportInterface;
-use OpenTelemetry\SDK\Registry;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Trace\SpanExporter\SpanExporterFactoryInterface;
 use OpenTelemetry\SDK\Trace\SpanExporterInterface;
 
@@ -48,8 +48,7 @@ private function buildTransport(): TransportInterface
         $compression = $this->getCompression();
         $timeout = $this->getTimeout();
 
-        $factoryClass = Registry::transportFactory($protocol);
-        $factory = $this->transportFactory ?: new $factoryClass();
+        $factory = $this->transportFactory ?? Loader::transportFactory($protocol);
 
         return $factory->create($endpoint, $contentType, $headers, $compression, $timeout);
     }
@@ -91,4 +90,14 @@ private function getTimeout(): float
 
         return $value/1000;
     }
+
+    public function type(): string
+    {
+        return 'otlp';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/Contrib/Otlp/StdoutLogsExporterFactory.php b/src/Contrib/Otlp/StdoutLogsExporterFactory.php
index d39c71e6a..8a8a7fde3 100644
--- a/src/Contrib/Otlp/StdoutLogsExporterFactory.php
+++ b/src/Contrib/Otlp/StdoutLogsExporterFactory.php
@@ -16,4 +16,14 @@ public function create(): LogRecordExporterInterface
 
         return new LogsExporter($transport);
     }
+
+    public function type(): string
+    {
+        return 'otlp/stdout';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/Contrib/Otlp/StdoutMetricExporterFactory.php b/src/Contrib/Otlp/StdoutMetricExporterFactory.php
index 3eeba09e2..73fac05c8 100644
--- a/src/Contrib/Otlp/StdoutMetricExporterFactory.php
+++ b/src/Contrib/Otlp/StdoutMetricExporterFactory.php
@@ -16,4 +16,14 @@ public function create(): MetricExporterInterface
 
         return new MetricExporter($transport);
     }
+
+    public function type(): string
+    {
+        return 'otlp/stdout';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/Contrib/Otlp/StdoutSpanExporterFactory.php b/src/Contrib/Otlp/StdoutSpanExporterFactory.php
index d51cbaa75..831fbfc50 100644
--- a/src/Contrib/Otlp/StdoutSpanExporterFactory.php
+++ b/src/Contrib/Otlp/StdoutSpanExporterFactory.php
@@ -16,4 +16,14 @@ public function create(): SpanExporterInterface
 
         return new SpanExporter($transport);
     }
+
+    public function type(): string
+    {
+        return 'otlp/stdout';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/Contrib/Otlp/_register.php b/src/Contrib/Otlp/_register.php
index 5f9d15af6..31060a6b2 100644
--- a/src/Contrib/Otlp/_register.php
+++ b/src/Contrib/Otlp/_register.php
@@ -1,13 +1,23 @@
 <?php
 
 declare(strict_types=1);
-\OpenTelemetry\SDK\Registry::registerSpanExporterFactory('otlp', \OpenTelemetry\Contrib\Otlp\SpanExporterFactory::class);
-\OpenTelemetry\SDK\Registry::registerSpanExporterFactory('otlp/stdout', \OpenTelemetry\Contrib\Otlp\StdoutSpanExporterFactory::class);
 
-\OpenTelemetry\SDK\Registry::registerMetricExporterFactory('otlp', \OpenTelemetry\Contrib\Otlp\MetricExporterFactory::class);
-\OpenTelemetry\SDK\Registry::registerMetricExporterFactory('otlp/stdout', \OpenTelemetry\Contrib\Otlp\StdoutMetricExporterFactory::class);
+use Nevay\SPI\ServiceLoader;
+use OpenTelemetry\Contrib\Otlp\LogsExporterFactory;
+use OpenTelemetry\Contrib\Otlp\MetricExporterFactory;
+use OpenTelemetry\Contrib\Otlp\SpanExporterFactory;
+use OpenTelemetry\Contrib\Otlp\StdoutLogsExporterFactory;
+use OpenTelemetry\Contrib\Otlp\StdoutMetricExporterFactory;
+use OpenTelemetry\Contrib\Otlp\StdoutSpanExporterFactory;
+use OpenTelemetry\SDK\Logs\LogRecordExporterFactoryInterface;
+use OpenTelemetry\SDK\Metrics\MetricExporterFactoryInterface;
+use OpenTelemetry\SDK\Trace\SpanExporter\SpanExporterFactoryInterface;
 
-\OpenTelemetry\SDK\Registry::registerTransportFactory('http', \OpenTelemetry\Contrib\Otlp\OtlpHttpTransportFactory::class);
+ServiceLoader::register(SpanExporterFactoryInterface::class, SpanExporterFactory::class);
+ServiceLoader::register(SpanExporterFactoryInterface::class, StdoutSpanExporterFactory::class);
 
-\OpenTelemetry\SDK\Registry::registerLogRecordExporterFactory('otlp', \OpenTelemetry\Contrib\Otlp\LogsExporterFactory::class);
-\OpenTelemetry\SDK\Registry::registerLogRecordExporterFactory('otlp/stdout', \OpenTelemetry\Contrib\Otlp\StdoutLogsExporterFactory::class);
+ServiceLoader::register(MetricExporterFactoryInterface::class, MetricExporterFactory::class);
+ServiceLoader::register(MetricExporterFactoryInterface::class, StdoutMetricExporterFactory::class);
+
+ServiceLoader::register(LogRecordExporterFactoryInterface::class, LogsExporterFactory::class);
+ServiceLoader::register(LogRecordExporterFactoryInterface::class, StdoutLogsExporterFactory::class);
diff --git a/src/Contrib/Otlp/composer.json b/src/Contrib/Otlp/composer.json
index c653dc18d..be792c76b 100644
--- a/src/Contrib/Otlp/composer.json
+++ b/src/Contrib/Otlp/composer.json
@@ -21,7 +21,8 @@
     "php-http/discovery": "^1.14",
     "open-telemetry/gen-otlp-protobuf": "^1.1",
     "open-telemetry/api": "^1.0|^2.0",
-    "open-telemetry/sdk": "^1.0|^2.0"
+    "open-telemetry/sdk": "^1.0|^2.0",
+    "tbachert/spi": "^1.0.1"
   },
   "suggest": {
   },
@@ -37,6 +38,10 @@
     "branch-alias": {
       "dev-main": "1.0.x-dev",
       "dev-2.x": "2.x-dev"
+    },
+    "spi-config": {
+      "autoload-files": true,
+      "prune-autoload-files": true
     }
   }
 }
diff --git a/src/Contrib/Zipkin/SpanExporterFactory.php b/src/Contrib/Zipkin/SpanExporterFactory.php
index 0714d48da..d8de8d2a7 100644
--- a/src/Contrib/Zipkin/SpanExporterFactory.php
+++ b/src/Contrib/Zipkin/SpanExporterFactory.php
@@ -20,4 +20,14 @@ public function create(): SpanExporterInterface
 
         return new Exporter($transport);
     }
+
+    public function type(): string
+    {
+        return 'zipkin';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/Contrib/Zipkin/_register.php b/src/Contrib/Zipkin/_register.php
index 3fcb692fb..45f4aa9ec 100644
--- a/src/Contrib/Zipkin/_register.php
+++ b/src/Contrib/Zipkin/_register.php
@@ -2,4 +2,8 @@
 
 declare(strict_types=1);
 
-\OpenTelemetry\SDK\Registry::registerSpanExporterFactory('zipkin', \OpenTelemetry\Contrib\Zipkin\SpanExporterFactory::class);
+use Nevay\SPI\ServiceLoader;
+use OpenTelemetry\Contrib\Zipkin\SpanExporterFactory;
+use OpenTelemetry\SDK\Trace\SpanExporter\SpanExporterFactoryInterface;
+
+ServiceLoader::register(SpanExporterFactoryInterface::class, SpanExporterFactory::class);
diff --git a/src/Contrib/Zipkin/composer.json b/src/Contrib/Zipkin/composer.json
index ba9896d30..4d8bed531 100644
--- a/src/Contrib/Zipkin/composer.json
+++ b/src/Contrib/Zipkin/composer.json
@@ -22,7 +22,8 @@
     "open-telemetry/sdk": "^1.0|^2.0",
     "php-http/async-client-implementation": "^1.0",
     "php-http/discovery": "^1.14",
-    "psr/http-factory-implementation": "^1.0"
+    "psr/http-factory-implementation": "^1.0",
+    "tbachert/spi": "^1.0.1"
   },
   "autoload": {
     "psr-4": {
@@ -36,6 +37,10 @@
     "branch-alias": {
       "dev-main": "1.0.x-dev",
       "dev-2.x": "2.x-dev"
+    },
+    "spi-config": {
+      "autoload-files": true,
+      "prune-autoload-files": true
     }
   }
 }
diff --git a/src/Extension/Propagator/B3/_register.php b/src/Extension/Propagator/B3/_register.php
deleted file mode 100644
index 72e30cee0..000000000
--- a/src/Extension/Propagator/B3/_register.php
+++ /dev/null
@@ -1,19 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-use OpenTelemetry\Extension\Propagator\B3\B3Propagator;
-use OpenTelemetry\SDK\Registry;
-
-if (!class_exists(Registry::class)) {
-    return;
-}
-
-Registry::registerTextMapPropagator(
-    'b3',
-    B3Propagator::getB3SingleHeaderInstance()
-);
-Registry::registerTextMapPropagator(
-    'b3multi',
-    B3Propagator::getB3MultiHeaderInstance()
-);
diff --git a/src/Extension/Propagator/B3/composer.json b/src/Extension/Propagator/B3/composer.json
index 790ca173c..abd16023b 100644
--- a/src/Extension/Propagator/B3/composer.json
+++ b/src/Extension/Propagator/B3/composer.json
@@ -24,10 +24,7 @@
     "autoload": {
         "psr-4": {
             "OpenTelemetry\\Extension\\Propagator\\B3\\": "."
-        },
-        "files": [
-            "_register.php"
-        ]
+        }
     },
     "extra": {
         "branch-alias": {
diff --git a/src/Extension/Propagator/CloudTrace/_register.php b/src/Extension/Propagator/CloudTrace/_register.php
deleted file mode 100644
index 5fcac7243..000000000
--- a/src/Extension/Propagator/CloudTrace/_register.php
+++ /dev/null
@@ -1,20 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-use OpenTelemetry\Extension\Propagator\CloudTrace\CloudTracePropagator;
-use OpenTelemetry\SDK\Registry;
-
-if (!class_exists(Registry::class)) {
-    return;
-}
-
-Registry::registerTextMapPropagator(
-    'cloudtrace',
-    CloudTracePropagator::getInstance()
-);
-
-Registry::registerTextMapPropagator(
-    'cloudtrace-oneway',
-    CloudTracePropagator::getOneWayInstance()
-);
diff --git a/src/Extension/Propagator/CloudTrace/composer.json b/src/Extension/Propagator/CloudTrace/composer.json
index 818ee206d..bbc1b55d9 100644
--- a/src/Extension/Propagator/CloudTrace/composer.json
+++ b/src/Extension/Propagator/CloudTrace/composer.json
@@ -24,10 +24,7 @@
     "autoload": {
         "psr-4": {
             "OpenTelemetry\\Extension\\Propagator\\CloudTrace\\": "."
-        },
-        "files": [
-            "_register.php"
-        ]
+        }
     },
     "extra": {
         "branch-alias": {
diff --git a/src/Extension/Propagator/Jaeger/_register.php b/src/Extension/Propagator/Jaeger/_register.php
deleted file mode 100644
index f1b7eb2c6..000000000
--- a/src/Extension/Propagator/Jaeger/_register.php
+++ /dev/null
@@ -1,21 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-use OpenTelemetry\Extension\Propagator\Jaeger\JaegerBaggagePropagator;
-use OpenTelemetry\Extension\Propagator\Jaeger\JaegerPropagator;
-use OpenTelemetry\SDK\Registry;
-
-if (!class_exists(Registry::class)) {
-    return;
-}
-
-Registry::registerTextMapPropagator(
-    'jaeger',
-    JaegerPropagator::getInstance()
-);
-
-Registry::registerTextMapPropagator(
-    'jaeger-baggage',
-    JaegerBaggagePropagator::getInstance()
-);
diff --git a/src/Extension/Propagator/Jaeger/composer.json b/src/Extension/Propagator/Jaeger/composer.json
index 6a8808392..c8dbbca4c 100644
--- a/src/Extension/Propagator/Jaeger/composer.json
+++ b/src/Extension/Propagator/Jaeger/composer.json
@@ -24,10 +24,7 @@
     "autoload": {
         "psr-4": {
             "OpenTelemetry\\Extension\\Propagator\\Jaeger\\": "."
-        },
-        "files": [
-            "_register.php"
-        ]
+        }
     },
     "extra": {
         "branch-alias": {
diff --git a/src/SDK/Common/Export/Http/PsrTransportFactory.php b/src/SDK/Common/Export/Http/PsrTransportFactory.php
index 433ef7c31..918762e25 100644
--- a/src/SDK/Common/Export/Http/PsrTransportFactory.php
+++ b/src/SDK/Common/Export/Http/PsrTransportFactory.php
@@ -74,4 +74,14 @@ public static function discover(): self
             Psr17FactoryDiscovery::findStreamFactory(),
         );
     }
+
+    public function type(): string
+    {
+        return 'http';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/SDK/Common/Export/Http/PsrUtils.php b/src/SDK/Common/Export/Http/PsrUtils.php
index 1639ba471..349090c6d 100644
--- a/src/SDK/Common/Export/Http/PsrUtils.php
+++ b/src/SDK/Common/Export/Http/PsrUtils.php
@@ -115,9 +115,9 @@ public static function decode(string $value, array $encodings): string
     public static function compression($compression): array
     {
         if (is_array($compression)) {
-            return $compression;
+            return array_filter($compression, fn ($value): bool => $value !== 'none');
         }
-        if (!$compression) {
+        if ($compression === 'none' || !$compression) {
             return [];
         }
         if (!str_contains((string) $compression, ',')) {
diff --git a/src/SDK/Common/Export/Stream/StreamTransportFactory.php b/src/SDK/Common/Export/Stream/StreamTransportFactory.php
index c6544bbe5..1568e78fc 100644
--- a/src/SDK/Common/Export/Stream/StreamTransportFactory.php
+++ b/src/SDK/Common/Export/Stream/StreamTransportFactory.php
@@ -116,4 +116,14 @@ private static function createHeaderArray(string $contentType, array $headers):
 
         return $header;
     }
+
+    public function type(): string
+    {
+        return 'stream';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/SDK/Common/Export/TransportFactoryInterface.php b/src/SDK/Common/Export/TransportFactoryInterface.php
index a2dd3a1e1..92ad49876 100644
--- a/src/SDK/Common/Export/TransportFactoryInterface.php
+++ b/src/SDK/Common/Export/TransportFactoryInterface.php
@@ -4,7 +4,9 @@
 
 namespace OpenTelemetry\SDK\Common\Export;
 
-interface TransportFactoryInterface
+use OpenTelemetry\SDK\Common\Services\SpiLoadableInterface;
+
+interface TransportFactoryInterface extends SpiLoadableInterface
 {
     public const COMPRESSION_GZIP = 'gzip';
     public const COMPRESSION_DEFLATE = 'deflate';
diff --git a/src/SDK/Common/Services/Loader.php b/src/SDK/Common/Services/Loader.php
new file mode 100644
index 000000000..b4915a1cc
--- /dev/null
+++ b/src/SDK/Common/Services/Loader.php
@@ -0,0 +1,99 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Common\Services;
+
+use Nevay\SPI\ServiceLoader;
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\SDK\Common\Export\TransportFactoryInterface;
+use OpenTelemetry\SDK\Logs\LogRecordExporterFactoryInterface;
+use OpenTelemetry\SDK\Metrics\MetricExporterFactoryInterface;
+use OpenTelemetry\SDK\Propagation\TextMapPropagatorFactoryInterface;
+use OpenTelemetry\SDK\Resource\ResourceDetectorFactoryInterface;
+use OpenTelemetry\SDK\Resource\ResourceDetectorInterface;
+use OpenTelemetry\SDK\Trace\SpanExporter\SpanExporterFactoryInterface;
+use RuntimeException;
+
+/**
+ * Loads services from SPI, handling type and priority.
+ */
+class Loader
+{
+    /**
+     * @param class-string<SpiLoadableInterface> $class
+     * @phan-suppress PhanTypeNonVarPassByRef
+     */
+    private static function getFactory(string $class, string $type): mixed
+    {
+        $factories = iterator_to_array(ServiceLoader::load($class));
+        array_multisort(
+            array_map(static fn ($factory) => $factory->priority(), $factories),
+            SORT_DESC,
+            $factories,
+        );
+        foreach ($factories as $factory) {
+            if ($factory->type() === $type) {
+                return $factory;
+            }
+        }
+
+        return null;
+    }
+
+    public static function spanExporterFactory(string $exporter): SpanExporterFactoryInterface
+    {
+        return self::getFactory(SpanExporterFactoryInterface::class, $exporter)
+            ?? throw new RuntimeException('Span exporter factory not defined for: ' . $exporter);
+    }
+
+    public static function logRecordExporterFactory(string $exporter): LogRecordExporterFactoryInterface
+    {
+        return self::getFactory(LogRecordExporterFactoryInterface::class, $exporter)
+            ?? throw new RuntimeException('LogRecord exporter factory not defined for: ' . $exporter);
+    }
+
+    /**
+     * Get transport factory registered for protocol. If $protocol contains a content-type eg `http/xyz` then
+     * only the first part, `http`, is used.
+     */
+    public static function transportFactory(string $protocol): TransportFactoryInterface
+    {
+        $type = explode('/', $protocol)[0];
+
+        return self::getFactory(TransportFactoryInterface::class, $type)
+            ?? throw new RuntimeException('Transport factory not defined for protocol: ' . $type);
+    }
+
+    public static function metricExporterFactory(string $exporter): MetricExporterFactoryInterface
+    {
+        return self::getFactory(MetricExporterFactoryInterface::class, $exporter)
+            ?? throw new RuntimeException('Metric exporter factory not registered for protocol: ' . $exporter);
+    }
+
+    public static function textMapPropagator(string $name): TextMapPropagatorInterface
+    {
+        $factory = self::getFactory(TextMapPropagatorFactoryInterface::class, $name)
+            ?? throw new RuntimeException('Text map propagator not registered for: ' . $name);
+
+        return $factory->create();
+    }
+
+    public static function resourceDetector(string $name): ResourceDetectorInterface
+    {
+        $factory = self::getFactory(ResourceDetectorFactoryInterface::class, $name)
+            ?? throw new RuntimeException('Resource detector not registered for: ' . $name);
+
+        return $factory->create();
+    }
+
+    /**
+     * @return ResourceDetectorInterface[]
+     */
+    public static function resourceDetectors(): array
+    {
+        $factories = iterator_to_array(ServiceLoader::load(ResourceDetectorFactoryInterface::class));
+
+        return array_map(fn (ResourceDetectorFactoryInterface $factory) => $factory->create(), $factories);
+    }
+}
diff --git a/src/SDK/Common/Services/SpiLoadableInterface.php b/src/SDK/Common/Services/SpiLoadableInterface.php
new file mode 100644
index 000000000..714e412a1
--- /dev/null
+++ b/src/SDK/Common/Services/SpiLoadableInterface.php
@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Common\Services;
+
+interface SpiLoadableInterface
+{
+    public function type(): string;
+    public function priority(): int;
+}
diff --git a/src/SDK/Logs/Exporter/ConsoleExporterFactory.php b/src/SDK/Logs/Exporter/ConsoleExporterFactory.php
index a959540a0..f43435632 100644
--- a/src/SDK/Logs/Exporter/ConsoleExporterFactory.php
+++ b/src/SDK/Logs/Exporter/ConsoleExporterFactory.php
@@ -4,16 +4,26 @@
 
 namespace OpenTelemetry\SDK\Logs\Exporter;
 
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Logs\LogRecordExporterFactoryInterface;
 use OpenTelemetry\SDK\Logs\LogRecordExporterInterface;
-use OpenTelemetry\SDK\Registry;
 
 class ConsoleExporterFactory implements LogRecordExporterFactoryInterface
 {
     public function create(): LogRecordExporterInterface
     {
-        $transport = Registry::transportFactory('stream')->create('php://stdout', 'application/json');
+        $transport = Loader::transportFactory('stream')->create('php://stdout', 'application/json');
 
         return new ConsoleExporter($transport);
     }
+
+    public function type(): string
+    {
+        return 'console';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/SDK/Logs/Exporter/InMemoryExporterFactory.php b/src/SDK/Logs/Exporter/InMemoryExporterFactory.php
index 6f24defe0..aad5389d4 100644
--- a/src/SDK/Logs/Exporter/InMemoryExporterFactory.php
+++ b/src/SDK/Logs/Exporter/InMemoryExporterFactory.php
@@ -13,4 +13,14 @@ public function create(): LogRecordExporterInterface
     {
         return new InMemoryExporter();
     }
+
+    public function type(): string
+    {
+        return 'memory';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/SDK/Logs/Exporter/_register.php b/src/SDK/Logs/Exporter/_register.php
deleted file mode 100644
index 96958baa8..000000000
--- a/src/SDK/Logs/Exporter/_register.php
+++ /dev/null
@@ -1,6 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-\OpenTelemetry\SDK\Registry::registerLogRecordExporterFactory('console', \OpenTelemetry\SDK\Logs\Exporter\ConsoleExporterFactory::class);
-\OpenTelemetry\SDK\Registry::registerLogRecordExporterFactory('memory', \OpenTelemetry\SDK\Logs\Exporter\InMemoryExporterFactory::class);
diff --git a/src/SDK/Logs/ExporterFactory.php b/src/SDK/Logs/ExporterFactory.php
index ecd4af7ff..ceda9ba39 100644
--- a/src/SDK/Logs/ExporterFactory.php
+++ b/src/SDK/Logs/ExporterFactory.php
@@ -7,8 +7,8 @@
 use InvalidArgumentException;
 use OpenTelemetry\SDK\Common\Configuration\Configuration;
 use OpenTelemetry\SDK\Common\Configuration\Variables;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Logs\Exporter\NoopExporter;
-use OpenTelemetry\SDK\Registry;
 
 class ExporterFactory
 {
@@ -22,7 +22,7 @@ public function create(): LogRecordExporterInterface
         if ($exporter === 'none') {
             return new NoopExporter();
         }
-        $factory = Registry::logRecordExporterFactory($exporter);
+        $factory = Loader::logRecordExporterFactory($exporter);
 
         return $factory->create();
     }
diff --git a/src/SDK/Logs/LogRecordExporterFactoryInterface.php b/src/SDK/Logs/LogRecordExporterFactoryInterface.php
index 523bec1ba..153be9989 100644
--- a/src/SDK/Logs/LogRecordExporterFactoryInterface.php
+++ b/src/SDK/Logs/LogRecordExporterFactoryInterface.php
@@ -4,7 +4,9 @@
 
 namespace OpenTelemetry\SDK\Logs;
 
-interface LogRecordExporterFactoryInterface
+use OpenTelemetry\SDK\Common\Services\SpiLoadableInterface;
+
+interface LogRecordExporterFactoryInterface extends SpiLoadableInterface
 {
     public function create(): LogRecordExporterInterface;
 }
diff --git a/src/SDK/Metrics/MeterProviderFactory.php b/src/SDK/Metrics/MeterProviderFactory.php
index 0f62cec5f..993812b61 100644
--- a/src/SDK/Metrics/MeterProviderFactory.php
+++ b/src/SDK/Metrics/MeterProviderFactory.php
@@ -9,13 +9,13 @@
 use OpenTelemetry\SDK\Common\Configuration\Configuration;
 use OpenTelemetry\SDK\Common\Configuration\KnownValues;
 use OpenTelemetry\SDK\Common\Configuration\Variables;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Metrics\Exemplar\ExemplarFilter\AllExemplarFilter;
 use OpenTelemetry\SDK\Metrics\Exemplar\ExemplarFilter\NoneExemplarFilter;
 use OpenTelemetry\SDK\Metrics\Exemplar\ExemplarFilter\WithSampledTraceExemplarFilter;
 use OpenTelemetry\SDK\Metrics\Exemplar\ExemplarFilterInterface;
 use OpenTelemetry\SDK\Metrics\MetricExporter\NoopMetricExporter;
 use OpenTelemetry\SDK\Metrics\MetricReader\ExportingReader;
-use OpenTelemetry\SDK\Registry;
 use OpenTelemetry\SDK\Resource\ResourceInfo;
 use OpenTelemetry\SDK\Resource\ResourceInfoFactory;
 use OpenTelemetry\SDK\Sdk;
@@ -42,7 +42,7 @@ public function create(?ResourceInfo $resource = null): MeterProviderInterface
         $exporterName = $exporters[0];
 
         try {
-            $factory = Registry::metricExporterFactory($exporterName);
+            $factory = Loader::metricExporterFactory($exporterName);
             $exporter = $factory->create();
         } catch (\Throwable $t) {
             self::logWarning(sprintf('Unable to create %s meter provider: %s', $exporterName, $t->getMessage()));
diff --git a/src/SDK/Metrics/MetricExporter/ConsoleMetricExporterFactory.php b/src/SDK/Metrics/MetricExporter/ConsoleMetricExporterFactory.php
index 19088738d..df29ce3ac 100644
--- a/src/SDK/Metrics/MetricExporter/ConsoleMetricExporterFactory.php
+++ b/src/SDK/Metrics/MetricExporter/ConsoleMetricExporterFactory.php
@@ -13,4 +13,14 @@ public function create(): MetricExporterInterface
     {
         return new ConsoleMetricExporter();
     }
+
+    public function type(): string
+    {
+        return 'console';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/SDK/Metrics/MetricExporter/InMemoryExporterFactory.php b/src/SDK/Metrics/MetricExporter/InMemoryExporterFactory.php
index c72c7b169..f95eaa923 100644
--- a/src/SDK/Metrics/MetricExporter/InMemoryExporterFactory.php
+++ b/src/SDK/Metrics/MetricExporter/InMemoryExporterFactory.php
@@ -13,4 +13,14 @@ public function create(): MetricExporterInterface
     {
         return new InMemoryExporter();
     }
+
+    public function type(): string
+    {
+        return 'memory';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/SDK/Metrics/MetricExporter/NoopMetricExporterFactory.php b/src/SDK/Metrics/MetricExporter/NoopMetricExporterFactory.php
index ab2ab2af3..7abe564c1 100644
--- a/src/SDK/Metrics/MetricExporter/NoopMetricExporterFactory.php
+++ b/src/SDK/Metrics/MetricExporter/NoopMetricExporterFactory.php
@@ -13,4 +13,14 @@ public function create(): MetricExporterInterface
     {
         return new NoopMetricExporter();
     }
+
+    public function type(): string
+    {
+        return 'none';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/SDK/Metrics/MetricExporter/_register.php b/src/SDK/Metrics/MetricExporter/_register.php
deleted file mode 100644
index fba543d02..000000000
--- a/src/SDK/Metrics/MetricExporter/_register.php
+++ /dev/null
@@ -1,7 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-\OpenTelemetry\SDK\Registry::registerMetricExporterFactory('memory', \OpenTelemetry\SDK\Metrics\MetricExporter\InMemoryExporterFactory::class);
-\OpenTelemetry\SDK\Registry::registerMetricExporterFactory('console', \OpenTelemetry\SDK\Metrics\MetricExporter\ConsoleMetricExporterFactory::class);
-\OpenTelemetry\SDK\Registry::registerMetricExporterFactory('none', \OpenTelemetry\SDK\Metrics\MetricExporter\NoopMetricExporterFactory::class);
diff --git a/src/SDK/Metrics/MetricExporterFactoryInterface.php b/src/SDK/Metrics/MetricExporterFactoryInterface.php
index 0d2541821..452793af2 100644
--- a/src/SDK/Metrics/MetricExporterFactoryInterface.php
+++ b/src/SDK/Metrics/MetricExporterFactoryInterface.php
@@ -4,7 +4,9 @@
 
 namespace OpenTelemetry\SDK\Metrics;
 
-interface MetricExporterFactoryInterface
+use OpenTelemetry\SDK\Common\Services\SpiLoadableInterface;
+
+interface MetricExporterFactoryInterface extends SpiLoadableInterface
 {
     public function create(): MetricExporterInterface;
 }
diff --git a/src/SDK/Propagation/B3MultiPropagatorFactory.php b/src/SDK/Propagation/B3MultiPropagatorFactory.php
new file mode 100644
index 000000000..0d1e276fb
--- /dev/null
+++ b/src/SDK/Propagation/B3MultiPropagatorFactory.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Propagation;
+
+use Nevay\SPI\ServiceProviderDependency\PackageDependency;
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\Extension\Propagator\B3\B3Propagator;
+
+#[PackageDependency('open-telemetry/extension-propagator-b3', '^1')]
+class B3MultiPropagatorFactory implements TextMapPropagatorFactoryInterface
+{
+    public function create(): TextMapPropagatorInterface
+    {
+        return B3Propagator::getB3MultiHeaderInstance();
+    }
+
+    public function type(): string
+    {
+        return 'b3multi';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+}
diff --git a/src/SDK/Propagation/B3PropagatorFactory.php b/src/SDK/Propagation/B3PropagatorFactory.php
new file mode 100644
index 000000000..8cb8bd2f5
--- /dev/null
+++ b/src/SDK/Propagation/B3PropagatorFactory.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Propagation;
+
+use Nevay\SPI\ServiceProviderDependency\PackageDependency;
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\Extension\Propagator\B3\B3Propagator;
+
+#[PackageDependency('open-telemetry/extension-propagator-b3', '^1')]
+class B3PropagatorFactory implements TextMapPropagatorFactoryInterface
+{
+    public function create(): TextMapPropagatorInterface
+    {
+        return B3Propagator::getB3SingleHeaderInstance();
+    }
+
+    public function type(): string
+    {
+        return 'b3';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+}
diff --git a/src/SDK/Propagation/BaggagePropagatorFactory.php b/src/SDK/Propagation/BaggagePropagatorFactory.php
new file mode 100644
index 000000000..1bd1a26c8
--- /dev/null
+++ b/src/SDK/Propagation/BaggagePropagatorFactory.php
@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Propagation;
+
+;
+
+use OpenTelemetry\API\Baggage\Propagation\BaggagePropagator;
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\SDK\Common\Configuration\KnownValues;
+
+class BaggagePropagatorFactory implements TextMapPropagatorFactoryInterface
+{
+    public function create(): TextMapPropagatorInterface
+    {
+        return BaggagePropagator::getInstance();
+    }
+
+    public function type(): string
+    {
+        return KnownValues::VALUE_BAGGAGE;
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+}
diff --git a/src/SDK/Propagation/CloudTraceOneWayPropagatorFactory.php b/src/SDK/Propagation/CloudTraceOneWayPropagatorFactory.php
new file mode 100644
index 000000000..634c9ad0b
--- /dev/null
+++ b/src/SDK/Propagation/CloudTraceOneWayPropagatorFactory.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Propagation;
+
+use Nevay\SPI\ServiceProviderDependency\PackageDependency;
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\Extension\Propagator\CloudTrace\CloudTracePropagator;
+
+#[PackageDependency('open-telemetry/extension-propagator-cloudtrace', '^0')]
+class CloudTraceOneWayPropagatorFactory implements TextMapPropagatorFactoryInterface
+{
+    public function create(): TextMapPropagatorInterface
+    {
+        return CloudTracePropagator::getOneWayInstance();
+    }
+
+    public function type(): string
+    {
+        return 'cloudtrace-oneway';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+}
diff --git a/src/SDK/Propagation/CloudTracePropagatorFactory.php b/src/SDK/Propagation/CloudTracePropagatorFactory.php
new file mode 100644
index 000000000..4b632ed95
--- /dev/null
+++ b/src/SDK/Propagation/CloudTracePropagatorFactory.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Propagation;
+
+use Nevay\SPI\ServiceProviderDependency\PackageDependency;
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\Extension\Propagator\CloudTrace\CloudTracePropagator;
+
+#[PackageDependency('open-telemetry/extension-propagator-cloudtrace', '^0')]
+class CloudTracePropagatorFactory implements TextMapPropagatorFactoryInterface
+{
+    public function create(): TextMapPropagatorInterface
+    {
+        return CloudTracePropagator::getInstance();
+    }
+
+    public function type(): string
+    {
+        return 'cloudtrace';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+}
diff --git a/src/SDK/Propagation/JaegerBaggagePropagatorFactory.php b/src/SDK/Propagation/JaegerBaggagePropagatorFactory.php
new file mode 100644
index 000000000..5dbbda2b4
--- /dev/null
+++ b/src/SDK/Propagation/JaegerBaggagePropagatorFactory.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Propagation;
+
+use Nevay\SPI\ServiceProviderDependency\PackageDependency;
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\Extension\Propagator\Jaeger\JaegerBaggagePropagator;
+
+#[PackageDependency('open-telemetry/extension-propagator-jaeger', '^0')]
+class JaegerBaggagePropagatorFactory implements TextMapPropagatorFactoryInterface
+{
+    public function create(): TextMapPropagatorInterface
+    {
+        return JaegerBaggagePropagator::getInstance();
+    }
+
+    public function type(): string
+    {
+        return 'jaeger-baggage';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+}
diff --git a/src/SDK/Propagation/JaegerPropagatorFactory.php b/src/SDK/Propagation/JaegerPropagatorFactory.php
new file mode 100644
index 000000000..6884064ed
--- /dev/null
+++ b/src/SDK/Propagation/JaegerPropagatorFactory.php
@@ -0,0 +1,28 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Propagation;
+
+use Nevay\SPI\ServiceProviderDependency\PackageDependency;
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\Extension\Propagator\Jaeger\JaegerPropagator;
+
+#[PackageDependency('open-telemetry/extension-propagator-jaeger', '^0')]
+class JaegerPropagatorFactory implements TextMapPropagatorFactoryInterface
+{
+    public function create(): TextMapPropagatorInterface
+    {
+        return JaegerPropagator::getInstance();
+    }
+
+    public function type(): string
+    {
+        return 'jaeger';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+}
diff --git a/src/SDK/Propagation/PropagatorFactory.php b/src/SDK/Propagation/PropagatorFactory.php
index 66160aad3..f78915ff5 100644
--- a/src/SDK/Propagation/PropagatorFactory.php
+++ b/src/SDK/Propagation/PropagatorFactory.php
@@ -9,8 +9,9 @@
 use OpenTelemetry\Context\Propagation\NoopTextMapPropagator;
 use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
 use OpenTelemetry\SDK\Common\Configuration\Configuration;
+use OpenTelemetry\SDK\Common\Configuration\KnownValues;
 use OpenTelemetry\SDK\Common\Configuration\Variables;
-use OpenTelemetry\SDK\Registry;
+use OpenTelemetry\SDK\Common\Services\Loader;
 
 class PropagatorFactory
 {
@@ -42,10 +43,16 @@ private function buildPropagators(array $names): array
 
     private function buildPropagator(string $name): TextMapPropagatorInterface
     {
-        try {
-            return Registry::textMapPropagator($name);
-        } catch (\RuntimeException $e) {
-            self::logWarning($e->getMessage());
+        switch ($name) {
+            case KnownValues::VALUE_NOOP:
+            case KnownValues::VALUE_NONE:
+                return NoopTextMapPropagator::getInstance();
+            default:
+                try {
+                    return Loader::textMapPropagator($name);
+                } catch (\RuntimeException $e) {
+                    self::logWarning($e->getMessage());
+                }
         }
 
         return NoopTextMapPropagator::getInstance();
diff --git a/src/SDK/Propagation/TextMapPropagatorFactoryInterface.php b/src/SDK/Propagation/TextMapPropagatorFactoryInterface.php
new file mode 100644
index 000000000..02858063f
--- /dev/null
+++ b/src/SDK/Propagation/TextMapPropagatorFactoryInterface.php
@@ -0,0 +1,13 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Propagation;
+
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\SDK\Common\Services\SpiLoadableInterface;
+
+interface TextMapPropagatorFactoryInterface extends SpiLoadableInterface
+{
+    public function create(): TextMapPropagatorInterface;
+}
diff --git a/src/SDK/Propagation/TraceContextPropagatorFactory.php b/src/SDK/Propagation/TraceContextPropagatorFactory.php
new file mode 100644
index 000000000..19361ea08
--- /dev/null
+++ b/src/SDK/Propagation/TraceContextPropagatorFactory.php
@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Propagation;
+
+;
+
+use OpenTelemetry\API\Trace\Propagation\TraceContextPropagator;
+use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\SDK\Common\Configuration\KnownValues;
+
+class TraceContextPropagatorFactory implements TextMapPropagatorFactoryInterface
+{
+    public function create(): TextMapPropagatorInterface
+    {
+        return TraceContextPropagator::getInstance();
+    }
+
+    public function type(): string
+    {
+        return KnownValues::VALUE_TRACECONTEXT;
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
+}
diff --git a/src/SDK/Propagation/_register.php b/src/SDK/Propagation/_register.php
deleted file mode 100644
index fd90da184..000000000
--- a/src/SDK/Propagation/_register.php
+++ /dev/null
@@ -1,16 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-\OpenTelemetry\SDK\Registry::registerTextMapPropagator(
-    \OpenTelemetry\SDK\Common\Configuration\KnownValues::VALUE_BAGGAGE,
-    \OpenTelemetry\API\Baggage\Propagation\BaggagePropagator::getInstance()
-);
-\OpenTelemetry\SDK\Registry::registerTextMapPropagator(
-    \OpenTelemetry\SDK\Common\Configuration\KnownValues::VALUE_TRACECONTEXT,
-    \OpenTelemetry\API\Trace\Propagation\TraceContextPropagator::getInstance()
-);
-\OpenTelemetry\SDK\Registry::registerTextMapPropagator(
-    \OpenTelemetry\SDK\Common\Configuration\KnownValues::VALUE_NONE,
-    \OpenTelemetry\Context\Propagation\NoopTextMapPropagator::getInstance()
-);
diff --git a/src/SDK/Registry.php b/src/SDK/Registry.php
deleted file mode 100644
index 300a8a40c..000000000
--- a/src/SDK/Registry.php
+++ /dev/null
@@ -1,205 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace OpenTelemetry\SDK;
-
-use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
-use OpenTelemetry\SDK\Common\Export\TransportFactoryInterface;
-use OpenTelemetry\SDK\Logs\LogRecordExporterFactoryInterface;
-use OpenTelemetry\SDK\Metrics\MetricExporterFactoryInterface;
-use OpenTelemetry\SDK\Resource\ResourceDetectorInterface;
-use OpenTelemetry\SDK\Trace\SpanExporter\SpanExporterFactoryInterface;
-use RuntimeException;
-use TypeError;
-
-/**
- * A registry to enable central registration of components that the SDK requires but which may be provided
- * by non-SDK modules, such as contrib and extension.
- * @todo [breaking] deprecate this mechanism of setting up components, in favor of using SPI.
- */
-class Registry
-{
-    private static array $spanExporterFactories = [];
-    private static array $transportFactories = [];
-    private static array $metricExporterFactories = [];
-    private static array $textMapPropagators = [];
-    private static array $logRecordExporterFactories = [];
-    private static array $resourceDetectors = [];
-
-    /**
-     * @param TransportFactoryInterface|class-string<TransportFactoryInterface> $factory
-     * @throws TypeError
-     */
-    public static function registerTransportFactory(string $protocol, TransportFactoryInterface|string $factory, bool $clobber = false): void
-    {
-        if (!$clobber && array_key_exists($protocol, self::$transportFactories)) {
-            return;
-        }
-        if (!is_subclass_of($factory, TransportFactoryInterface::class)) {
-            throw new TypeError(
-                sprintf(
-                    'Cannot register transport factory: %s must exist and implement %s',
-                    is_string($factory) ? $factory : $factory::class,
-                    TransportFactoryInterface::class
-                )
-            );
-        }
-        self::$transportFactories[$protocol] = $factory;
-    }
-
-    /**
-     * @param SpanExporterFactoryInterface|class-string<SpanExporterFactoryInterface> $factory
-     * @throws TypeError
-     */
-    public static function registerSpanExporterFactory(string $exporter, SpanExporterFactoryInterface|string $factory, bool $clobber = false): void
-    {
-        if (!$clobber && array_key_exists($exporter, self::$spanExporterFactories)) {
-            return;
-        }
-        if (!is_subclass_of($factory, SpanExporterFactoryInterface::class)) {
-            throw new TypeError(
-                sprintf(
-                    'Cannot register span exporter factory: %s must exist and implement %s',
-                    is_string($factory) ? $factory : $factory::class,
-                    SpanExporterFactoryInterface::class
-                )
-            );
-        }
-        self::$spanExporterFactories[$exporter] = $factory;
-    }
-
-    /**
-     * @param MetricExporterFactoryInterface|class-string<MetricExporterFactoryInterface> $factory
-     * @throws TypeError
-     */
-    public static function registerMetricExporterFactory(string $exporter, MetricExporterFactoryInterface|string $factory, bool $clobber = false): void
-    {
-        if (!$clobber && array_key_exists($exporter, self::$metricExporterFactories)) {
-            return;
-        }
-        if (!is_subclass_of($factory, MetricExporterFactoryInterface::class)) {
-            throw new TypeError(
-                sprintf(
-                    'Cannot register metric factory: %s must exist and implement %s',
-                    is_string($factory) ? $factory : $factory::class,
-                    MetricExporterFactoryInterface::class
-                )
-            );
-        }
-        self::$metricExporterFactories[$exporter] = $factory;
-    }
-
-    /**
-     * @param LogRecordExporterFactoryInterface|class-string<LogRecordExporterFactoryInterface> $factory
-     * @throws TypeError
-     */
-    public static function registerLogRecordExporterFactory(string $exporter, LogRecordExporterFactoryInterface|string $factory, bool $clobber = false): void
-    {
-        if (!$clobber && array_key_exists($exporter, self::$logRecordExporterFactories)) {
-            return;
-        }
-        if (!is_subclass_of($factory, LogRecordExporterFactoryInterface::class)) {
-            throw new TypeError(
-                sprintf(
-                    'Cannot register LogRecord exporter factory: %s must exist and implement %s',
-                    is_string($factory) ? $factory : $factory::class,
-                    LogRecordExporterFactoryInterface::class
-                )
-            );
-        }
-        self::$logRecordExporterFactories[$exporter] = $factory;
-    }
-
-    public static function registerTextMapPropagator(string $name, TextMapPropagatorInterface $propagator, bool $clobber = false): void
-    {
-        if (!$clobber && array_key_exists($name, self::$textMapPropagators)) {
-            return;
-        }
-        self::$textMapPropagators[$name] = $propagator;
-    }
-
-    public static function registerResourceDetector(string $name, ResourceDetectorInterface $detector): void
-    {
-        self::$resourceDetectors[$name] = $detector;
-    }
-
-    public static function spanExporterFactory(string $exporter): SpanExporterFactoryInterface
-    {
-        if (!array_key_exists($exporter, self::$spanExporterFactories)) {
-            throw new RuntimeException('Span exporter factory not defined for: ' . $exporter);
-        }
-        $class = self::$spanExporterFactories[$exporter];
-        $factory = (is_callable($class)) ? $class : new $class();
-        assert($factory instanceof SpanExporterFactoryInterface);
-
-        return $factory;
-    }
-
-    public static function logRecordExporterFactory(string $exporter): LogRecordExporterFactoryInterface
-    {
-        if (!array_key_exists($exporter, self::$logRecordExporterFactories)) {
-            throw new RuntimeException('LogRecord exporter factory not defined for: ' . $exporter);
-        }
-        $class = self::$logRecordExporterFactories[$exporter];
-        $factory = (is_callable($class)) ? $class : new $class();
-        assert($factory instanceof LogRecordExporterFactoryInterface);
-
-        return $factory;
-    }
-
-    /**
-     * Get transport factory registered for protocol. If $protocol contains a content-type eg `http/xyz` then
-     * only the first part, `http`, is used.
-     */
-    public static function transportFactory(string $protocol): TransportFactoryInterface
-    {
-        $protocol = explode('/', $protocol)[0];
-        if (!array_key_exists($protocol, self::$transportFactories)) {
-            throw new RuntimeException('Transport factory not defined for protocol: ' . $protocol);
-        }
-        $class = self::$transportFactories[$protocol];
-        $factory = (is_callable($class)) ? $class : new $class();
-        assert($factory instanceof TransportFactoryInterface);
-
-        return $factory;
-    }
-
-    public static function metricExporterFactory(string $exporter): MetricExporterFactoryInterface
-    {
-        if (!array_key_exists($exporter, self::$metricExporterFactories)) {
-            throw new RuntimeException('Metric exporter factory not registered for protocol: ' . $exporter);
-        }
-        $class = self::$metricExporterFactories[$exporter];
-        $factory = (is_callable($class)) ? $class : new $class();
-        assert($factory instanceof MetricExporterFactoryInterface);
-
-        return $factory;
-    }
-
-    public static function textMapPropagator(string $name): TextMapPropagatorInterface
-    {
-        if (!array_key_exists($name, self::$textMapPropagators)) {
-            throw new RuntimeException('Text map propagator not registered for: ' . $name);
-        }
-
-        return self::$textMapPropagators[$name];
-    }
-
-    public static function resourceDetector(string $name): ResourceDetectorInterface
-    {
-        if (!array_key_exists($name, self::$resourceDetectors)) {
-            throw new RuntimeException('Resource detector not registered for: ' . $name);
-        }
-
-        return self::$resourceDetectors[$name];
-    }
-
-    /**
-     * @return array<int, ResourceDetectorInterface>
-     */
-    public static function resourceDetectors(): array
-    {
-        return array_values(self::$resourceDetectors);
-    }
-}
diff --git a/src/SDK/Resource/ResourceDetectorFactoryInterface.php b/src/SDK/Resource/ResourceDetectorFactoryInterface.php
new file mode 100644
index 000000000..fd2698897
--- /dev/null
+++ b/src/SDK/Resource/ResourceDetectorFactoryInterface.php
@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenTelemetry\SDK\Resource;
+
+use OpenTelemetry\SDK\Common\Services\SpiLoadableInterface;
+
+interface ResourceDetectorFactoryInterface extends SpiLoadableInterface
+{
+    public function create(): ResourceDetectorInterface;
+}
diff --git a/src/SDK/Resource/ResourceInfoFactory.php b/src/SDK/Resource/ResourceInfoFactory.php
index 62759ddb0..5ae27f6fb 100644
--- a/src/SDK/Resource/ResourceInfoFactory.php
+++ b/src/SDK/Resource/ResourceInfoFactory.php
@@ -10,7 +10,7 @@
 use OpenTelemetry\SDK\Common\Configuration\Configuration;
 use OpenTelemetry\SDK\Common\Configuration\KnownValues as Values;
 use OpenTelemetry\SDK\Common\Configuration\Variables as Env;
-use OpenTelemetry\SDK\Registry;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use RuntimeException;
 
 class ResourceInfoFactory
@@ -33,7 +33,7 @@ public static function defaultResource(): ResourceInfo
                 new Detectors\Sdk(),
                 new Detectors\SdkProvided(),
                 new Detectors\Composer(),
-                ...Registry::resourceDetectors(),
+                ...Loader::resourceDetectors(),
                 new Detectors\Environment(),
             ]))->getResource();
         }
@@ -84,7 +84,7 @@ public static function defaultResource(): ResourceInfo
                     break;
                 default:
                     try {
-                        $resourceDetectors[] = Registry::resourceDetector($detector);
+                        $resourceDetectors[] = Loader::resourceDetector($detector);
                     } catch (RuntimeException $e) {
                         self::logWarning($e->getMessage());
                     }
diff --git a/src/SDK/Trace/ExporterFactory.php b/src/SDK/Trace/ExporterFactory.php
index 9b652cc2f..eb3efadb2 100644
--- a/src/SDK/Trace/ExporterFactory.php
+++ b/src/SDK/Trace/ExporterFactory.php
@@ -7,7 +7,7 @@
 use InvalidArgumentException;
 use OpenTelemetry\SDK\Common\Configuration\Configuration;
 use OpenTelemetry\SDK\Common\Configuration\Variables;
-use OpenTelemetry\SDK\Registry;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use RuntimeException;
 
 class ExporterFactory
@@ -25,7 +25,7 @@ public function create(): ?SpanExporterInterface
         if ($exporter === 'none') {
             return null;
         }
-        $factory = Registry::spanExporterFactory($exporter);
+        $factory = Loader::spanExporterFactory($exporter);
 
         return $factory->create();
     }
diff --git a/src/SDK/Trace/SpanExporter/ConsoleSpanExporterFactory.php b/src/SDK/Trace/SpanExporter/ConsoleSpanExporterFactory.php
index 7e45fb549..40b04cbd2 100644
--- a/src/SDK/Trace/SpanExporter/ConsoleSpanExporterFactory.php
+++ b/src/SDK/Trace/SpanExporter/ConsoleSpanExporterFactory.php
@@ -4,15 +4,25 @@
 
 namespace OpenTelemetry\SDK\Trace\SpanExporter;
 
-use OpenTelemetry\SDK\Registry;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Trace\SpanExporterInterface;
 
 class ConsoleSpanExporterFactory implements SpanExporterFactoryInterface
 {
     public function create(): SpanExporterInterface
     {
-        $transport = Registry::transportFactory('stream')->create('php://stdout', 'application/json');
+        $transport = Loader::transportFactory('stream')->create('php://stdout', 'application/json');
 
         return new ConsoleSpanExporter($transport);
     }
+
+    public function type(): string
+    {
+        return 'console';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/SDK/Trace/SpanExporter/InMemorySpanExporterFactory.php b/src/SDK/Trace/SpanExporter/InMemorySpanExporterFactory.php
index c19686fac..473a82fc5 100644
--- a/src/SDK/Trace/SpanExporter/InMemorySpanExporterFactory.php
+++ b/src/SDK/Trace/SpanExporter/InMemorySpanExporterFactory.php
@@ -12,4 +12,14 @@ public function create(): SpanExporterInterface
     {
         return new InMemoryExporter();
     }
+
+    public function type(): string
+    {
+        return 'memory';
+    }
+
+    public function priority(): int
+    {
+        return 0;
+    }
 }
diff --git a/src/SDK/Trace/SpanExporter/SpanExporterFactoryInterface.php b/src/SDK/Trace/SpanExporter/SpanExporterFactoryInterface.php
index 8d44b35eb..98d24bd51 100644
--- a/src/SDK/Trace/SpanExporter/SpanExporterFactoryInterface.php
+++ b/src/SDK/Trace/SpanExporter/SpanExporterFactoryInterface.php
@@ -4,9 +4,10 @@
 
 namespace OpenTelemetry\SDK\Trace\SpanExporter;
 
+use OpenTelemetry\SDK\Common\Services\SpiLoadableInterface;
 use OpenTelemetry\SDK\Trace\SpanExporterInterface;
 
-interface SpanExporterFactoryInterface
+interface SpanExporterFactoryInterface extends SpiLoadableInterface
 {
     public function create(): SpanExporterInterface;
 }
diff --git a/src/SDK/Trace/SpanExporter/_register.php b/src/SDK/Trace/SpanExporter/_register.php
deleted file mode 100644
index aad07be42..000000000
--- a/src/SDK/Trace/SpanExporter/_register.php
+++ /dev/null
@@ -1,7 +0,0 @@
-<?php
-
-declare(strict_types=1);
-\OpenTelemetry\SDK\Registry::registerSpanExporterFactory('console', \OpenTelemetry\SDK\Trace\SpanExporter\ConsoleSpanExporterFactory::class);
-\OpenTelemetry\SDK\Registry::registerSpanExporterFactory('memory', \OpenTelemetry\SDK\Trace\SpanExporter\InMemorySpanExporterFactory::class);
-
-\OpenTelemetry\SDK\Registry::registerTransportFactory('stream', \OpenTelemetry\SDK\Common\Export\Stream\StreamTransportFactory::class);
diff --git a/src/SDK/_register.php b/src/SDK/_register.php
new file mode 100644
index 000000000..297edc750
--- /dev/null
+++ b/src/SDK/_register.php
@@ -0,0 +1,45 @@
+<?php
+
+declare(strict_types=1);
+
+use Nevay\SPI\ServiceLoader;
+use OpenTelemetry\SDK\Common\Export\Http\PsrTransportFactory;
+use OpenTelemetry\SDK\Common\Export\Stream\StreamTransportFactory;
+use OpenTelemetry\SDK\Common\Export\TransportFactoryInterface;
+use OpenTelemetry\SDK\Logs\Exporter as LogsExporter;
+use OpenTelemetry\SDK\Logs\LogRecordExporterFactoryInterface;
+use OpenTelemetry\SDK\Metrics\MetricExporter;
+use OpenTelemetry\SDK\Metrics\MetricExporterFactoryInterface;
+use OpenTelemetry\SDK\Propagation\B3MultiPropagatorFactory;
+use OpenTelemetry\SDK\Propagation\B3PropagatorFactory;
+use OpenTelemetry\SDK\Propagation\BaggagePropagatorFactory;
+use OpenTelemetry\SDK\Propagation\CloudTraceOneWayPropagatorFactory;
+use OpenTelemetry\SDK\Propagation\CloudTracePropagatorFactory;
+use OpenTelemetry\SDK\Propagation\JaegerBaggagePropagatorFactory;
+use OpenTelemetry\SDK\Propagation\JaegerPropagatorFactory;
+use OpenTelemetry\SDK\Propagation\TextMapPropagatorFactoryInterface;
+use OpenTelemetry\SDK\Propagation\TraceContextPropagatorFactory;
+use OpenTelemetry\SDK\Trace\SpanExporter;
+use OpenTelemetry\SDK\Trace\SpanExporter\SpanExporterFactoryInterface;
+
+ServiceLoader::register(TextMapPropagatorFactoryInterface::class, BaggagePropagatorFactory::class);
+ServiceLoader::register(TextMapPropagatorFactoryInterface::class, TraceContextPropagatorFactory::class);
+ServiceLoader::register(TextMapPropagatorFactoryInterface::class, B3PropagatorFactory::class);
+ServiceLoader::register(TextMapPropagatorFactoryInterface::class, B3MultiPropagatorFactory::class);
+ServiceLoader::register(TextMapPropagatorFactoryInterface::class, CloudTracePropagatorFactory::class);
+ServiceLoader::register(TextMapPropagatorFactoryInterface::class, CloudTraceOneWayPropagatorFactory::class);
+ServiceLoader::register(TextMapPropagatorFactoryInterface::class, JaegerPropagatorFactory::class);
+ServiceLoader::register(TextMapPropagatorFactoryInterface::class, JaegerBaggagePropagatorFactory::class);
+
+ServiceLoader::register(LogRecordExporterFactoryInterface::class, LogsExporter\ConsoleExporterFactory::class);
+ServiceLoader::register(LogRecordExporterFactoryInterface::class, LogsExporter\InMemoryExporterFactory::class);
+
+ServiceLoader::register(MetricExporterFactoryInterface::class, MetricExporter\InMemoryExporterFactory::class);
+ServiceLoader::register(MetricExporterFactoryInterface::class, MetricExporter\ConsoleMetricExporterFactory::class);
+ServiceLoader::register(MetricExporterFactoryInterface::class, MetricExporter\NoopMetricExporterFactory::class);
+
+ServiceLoader::register(SpanExporterFactoryInterface::class, SpanExporter\ConsoleSpanExporterFactory::class);
+ServiceLoader::register(SpanExporterFactoryInterface::class, SpanExporter\InMemorySpanExporterFactory::class);
+
+ServiceLoader::register(TransportFactoryInterface::class, StreamTransportFactory::class);
+ServiceLoader::register(TransportFactoryInterface::class, PsrTransportFactory::class);
diff --git a/src/SDK/composer.json b/src/SDK/composer.json
index f6bfeb4f4..102f750e5 100644
--- a/src/SDK/composer.json
+++ b/src/SDK/composer.json
@@ -39,10 +39,7 @@
         },
         "files": [
             "Common/Util/functions.php",
-            "Logs/Exporter/_register.php",
-            "Metrics/MetricExporter/_register.php",
-            "Propagation/_register.php",
-            "Trace/SpanExporter/_register.php",
+            "_register.php",
             "Common/Dev/Compatibility/_load.php",
             "_autoload.php"
         ]
@@ -57,10 +54,11 @@
             "dev-main": "1.0.x-dev",
             "dev-2.x": "2.x-dev"
         },
-        "spi": {
-            "OpenTelemetry\\API\\Instrumentation\\AutoInstrumentation\\HookManagerInterface": [
-                "OpenTelemetry\\API\\Instrumentation\\AutoInstrumentation\\ExtensionHookManager"
-            ]
+        "spi-config": {
+            "autoload-files": [
+                "_register.php"
+            ],
+            "prune-autoload-files": true
         }
     }
 }
diff --git a/tests/Unit/Contrib/Grpc/GrpcTransportFactoryTest.php b/tests/Unit/Contrib/Grpc/GrpcTransportFactoryTest.php
index 50fa771b0..3cb87f1cc 100644
--- a/tests/Unit/Contrib/Grpc/GrpcTransportFactoryTest.php
+++ b/tests/Unit/Contrib/Grpc/GrpcTransportFactoryTest.php
@@ -19,4 +19,16 @@ public function test_grpc_transport_create(): void
 
         $this->assertInstanceOf(TransportInterface::class, $transport);
     }
+
+    public function test_type(): void
+    {
+        $factory = new GrpcTransportFactory();
+        $this->assertSame('grpc', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new GrpcTransportFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/Contrib/Otlp/LogsExporterFactoryTest.php b/tests/Unit/Contrib/Otlp/LogsExporterFactoryTest.php
index 9a2d22f57..ae374a711 100644
--- a/tests/Unit/Contrib/Otlp/LogsExporterFactoryTest.php
+++ b/tests/Unit/Contrib/Otlp/LogsExporterFactoryTest.php
@@ -171,4 +171,16 @@ public static function configProvider(): array
             ],
         ];
     }
+
+    public function test_type(): void
+    {
+        $factory = new LogsExporterFactory();
+        $this->assertSame('otlp', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new LogsExporterFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/Contrib/Otlp/MetricExporterFactoryTest.php b/tests/Unit/Contrib/Otlp/MetricExporterFactoryTest.php
index 774800dd4..faaf33ded 100644
--- a/tests/Unit/Contrib/Otlp/MetricExporterFactoryTest.php
+++ b/tests/Unit/Contrib/Otlp/MetricExporterFactoryTest.php
@@ -229,4 +229,16 @@ public static function configProvider(): array
             ],
         ];
     }
+
+    public function test_type(): void
+    {
+        $factory = new MetricExporterFactory();
+        $this->assertSame('otlp', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new MetricExporterFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/Contrib/Otlp/OtlpHttpTransportFactoryTest.php b/tests/Unit/Contrib/Otlp/OtlpHttpTransportFactoryTest.php
deleted file mode 100644
index a0c11ddeb..000000000
--- a/tests/Unit/Contrib/Otlp/OtlpHttpTransportFactoryTest.php
+++ /dev/null
@@ -1,27 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace OpenTelemetry\Tests\Unit\Contrib\Otlp;
-
-use OpenTelemetry\Contrib\Otlp\OtlpHttpTransportFactory;
-use OpenTelemetry\SDK\Common\Export\Http\PsrTransport;
-use PHPUnit\Framework\Attributes\CoversClass;
-use PHPUnit\Framework\TestCase;
-
-#[CoversClass(OtlpHttpTransportFactory::class)]
-class OtlpHttpTransportFactoryTest extends TestCase
-{
-    private OtlpHttpTransportFactory $factory;
-
-    public function setUp(): void
-    {
-        $this->factory = new OtlpHttpTransportFactory();
-    }
-
-    public function test_factory_creates_psr_transport(): void
-    {
-        $transport = $this->factory->create('http://example.com', 'application/x-protobuf');
-        $this->assertInstanceOf(PsrTransport::class, $transport);
-    }
-}
diff --git a/tests/Unit/Contrib/Otlp/SpanExporterFactoryTest.php b/tests/Unit/Contrib/Otlp/SpanExporterFactoryTest.php
index 015801562..e055797dc 100644
--- a/tests/Unit/Contrib/Otlp/SpanExporterFactoryTest.php
+++ b/tests/Unit/Contrib/Otlp/SpanExporterFactoryTest.php
@@ -174,4 +174,16 @@ public static function configProvider(): array
             ],
         ];
     }
+
+    public function test_type(): void
+    {
+        $factory = new SpanExporterFactory();
+        $this->assertSame('otlp', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new SpanExporterFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/SDK/Common/Export/Http/PsrTransportTest.php b/tests/Unit/SDK/Common/Export/Http/PsrTransportTest.php
index dab731d93..800a1b094 100644
--- a/tests/Unit/SDK/Common/Export/Http/PsrTransportTest.php
+++ b/tests/Unit/SDK/Common/Export/Http/PsrTransportTest.php
@@ -203,4 +203,14 @@ public function test_force_flush_closed_returns_false(): void
 
         $this->assertFalse($transport->forceFlush());
     }
+
+    public function test_type(): void
+    {
+        $this->assertSame('http', $this->factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $this->assertSame(0, $this->factory->priority());
+    }
 }
diff --git a/tests/Unit/SDK/Common/Export/Http/PsrUtilsTest.php b/tests/Unit/SDK/Common/Export/Http/PsrUtilsTest.php
index c47430eef..b215148e3 100644
--- a/tests/Unit/SDK/Common/Export/Http/PsrUtilsTest.php
+++ b/tests/Unit/SDK/Common/Export/Http/PsrUtilsTest.php
@@ -108,9 +108,11 @@ public static function compressionProvider(): array
         return [
             ['gzip', ['gzip']],
             ['', []],
+            ['none', []],
             ['gzip,br', ['gzip','br']],
             ['gzip , brotli', ['gzip','brotli']],
             [['gzip'], ['gzip']],
+            [['gzip', 'none'], ['gzip']],
         ];
     }
 }
diff --git a/tests/Unit/SDK/Common/Export/Stream/StreamTransportFactoryTest.php b/tests/Unit/SDK/Common/Export/Stream/StreamTransportFactoryTest.php
index cd6b2cc0a..cc30a3d05 100644
--- a/tests/Unit/SDK/Common/Export/Stream/StreamTransportFactoryTest.php
+++ b/tests/Unit/SDK/Common/Export/Stream/StreamTransportFactoryTest.php
@@ -18,4 +18,16 @@ public function test_creates_stream(): void
         $this->expectOutputString('payload');
         $transport->send('payload')->await();
     }
+
+    public function test_type(): void
+    {
+        $factory = new StreamTransportFactory();
+        $this->assertSame('stream', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new StreamTransportFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/SDK/FactoryRegistryTest.php b/tests/Unit/SDK/Common/Services/LoaderTest.php
similarity index 51%
rename from tests/Unit/SDK/FactoryRegistryTest.php
rename to tests/Unit/SDK/Common/Services/LoaderTest.php
index d58842375..50f30d048 100644
--- a/tests/Unit/SDK/FactoryRegistryTest.php
+++ b/tests/Unit/SDK/Common/Services/LoaderTest.php
@@ -2,26 +2,33 @@
 
 declare(strict_types=1);
 
-namespace OpenTelemetry\Tests\Unit\SDK;
+namespace OpenTelemetry\Tests\Unit\SDK\Common\Services;
 
+use Nevay\SPI\ServiceLoader;
 use OpenTelemetry\Context\Propagation\TextMapPropagatorInterface;
+use OpenTelemetry\SDK\Common\Attribute\Attributes;
 use OpenTelemetry\SDK\Common\Export\TransportFactoryInterface;
+use OpenTelemetry\SDK\Common\Services\Loader;
 use OpenTelemetry\SDK\Logs\LogRecordExporterFactoryInterface;
 use OpenTelemetry\SDK\Metrics\MetricExporterFactoryInterface;
-use OpenTelemetry\SDK\Registry;
+use OpenTelemetry\SDK\Resource\ResourceDetectorFactoryInterface;
+use OpenTelemetry\SDK\Resource\ResourceDetectorInterface;
+use OpenTelemetry\SDK\Resource\ResourceInfo;
 use OpenTelemetry\SDK\Trace\SpanExporter\SpanExporterFactoryInterface;
+use OpenTelemetry\Tests\TestState;
 use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
-use TypeError;
 
-#[CoversClass(Registry::class)]
-class FactoryRegistryTest extends TestCase
+#[CoversClass(Loader::class)]
+class LoaderTest extends TestCase
 {
+    use TestState;
+
     #[DataProvider('transportProtocolsProvider')]
     public function test_default_transport_factories(string $name): void
     {
-        $factory = Registry::transportFactory($name);
+        $factory = Loader::transportFactory($name);
         $this->assertInstanceOf(TransportFactoryInterface::class, $factory);
     }
 
@@ -40,7 +47,7 @@ public static function transportProtocolsProvider(): array
     #[DataProvider('spanExporterProvider')]
     public function test_default_span_exporter_factories(string $name): void
     {
-        $factory = Registry::spanExporterFactory($name);
+        $factory = Loader::spanExporterFactory($name);
         $this->assertInstanceOf(SpanExporterFactoryInterface::class, $factory);
     }
 
@@ -57,7 +64,7 @@ public static function spanExporterProvider(): array
     #[DataProvider('metricExporterProvider')]
     public function test_default_metric_exporter_factories(string $name): void
     {
-        $factory = Registry::metricExporterFactory($name);
+        $factory = Loader::metricExporterFactory($name);
         $this->assertInstanceOf(MetricExporterFactoryInterface::class, $factory);
     }
 
@@ -73,7 +80,7 @@ public static function metricExporterProvider(): array
     #[DataProvider('logRecordExporterProvider')]
     public function test_default_log_record_exporter_factories(string $name): void
     {
-        $factory = Registry::logRecordExporterFactory($name);
+        $factory = Loader::logRecordExporterFactory($name);
         $this->assertInstanceOf(LogRecordExporterFactoryInterface::class, $factory);
     }
 
@@ -88,7 +95,7 @@ public static function logRecordExporterProvider(): array
     #[DataProvider('textMapPropagator')]
     public function test_default_text_map_propagator(string $name): void
     {
-        $propagator = Registry::textMapPropagator($name);
+        $propagator = Loader::textMapPropagator($name);
         $this->assertInstanceOf(TextMapPropagatorInterface::class, $propagator);
     }
 
@@ -106,39 +113,56 @@ public static function textMapPropagator(): array
         ];
     }
 
-    #[DataProvider('invalidFactoryProvider')]
-    public function test_register_invalid_transport_factory($factory): void
+    public function test_retrieve_from_spi(): void
     {
-        $this->expectException(TypeError::class);
-        Registry::registerTransportFactory('http', $factory, true);
+        $this->assertFileExists(dirname(__DIR__, 5) . '/vendor/composer/GeneratedServiceProviderData.php');
+        $this->assertInstanceOf(ResourceDetectorInterface::class, Loader::resourceDetector('test'));
     }
 
-    #[DataProvider('invalidFactoryProvider')]
-    public function test_register_invalid_span_exporter_factory($factory): void
+    public function test_add_to_spi(): void
     {
-        $this->expectException(TypeError::class);
-        Registry::registerSpanExporterFactory('foo', $factory, true);
+        $factory = new class() implements ResourceDetectorFactoryInterface {
+            public function create(): ResourceDetectorInterface
+            {
+                return new class() implements ResourceDetectorInterface {
+                    public function getResource(): ResourceInfo
+                    {
+                        return ResourceInfo::create(Attributes::create(['foo-resource' => 'foo']));
+                    }
+                };
+            }
+            public function type(): string
+            {
+                return 'foo';
+            }
+            public function priority(): int
+            {
+                return 99;
+            }
+        };
+        ServiceLoader::register(ResourceDetectorFactoryInterface::class, $factory::class);
+
+        $detector = Loader::resourceDetector('foo');
+        $this->assertInstanceOf(ResourceDetectorInterface::class, $detector);
+        $this->assertTrue($detector->getResource()->getAttributes()->has('foo-resource'));
+        $this->assertSame('foo', $detector->getResource()->getAttributes()->get('foo-resource'));
     }
 
-    #[DataProvider('invalidFactoryProvider')]
-    public function test_register_invalid_metric_exporter_factory($factory): void
+    public function test_get_all_resource_detectors(): void
     {
-        $this->expectException(TypeError::class);
-        Registry::registerMetricExporterFactory('foo', $factory, true);
+        $detectors = Loader::resourceDetectors();
+        $this->assertNotEmpty($detectors);
     }
 
-    #[DataProvider('invalidFactoryProvider')]
-    public function test_register_invalid_log_record_exporter_factory($factory): void
+    public function test_missing_propagator(): void
     {
-        $this->expectException(TypeError::class);
-        Registry::registerLogRecordExporterFactory('foo', $factory, true);
+        $this->expectException(\RuntimeException::class);
+        Loader::textMapPropagator('missing');
     }
 
-    public static function invalidFactoryProvider(): array
+    public function test_missing_detector(): void
     {
-        return [
-            [new \stdClass()],
-            ['\stdClass'],
-        ];
+        $this->expectException(\RuntimeException::class);
+        Loader::resourceDetector('missing');
     }
 }
diff --git a/tests/Unit/SDK/Logs/Exporter/ConsoleExporterFactoryTest.php b/tests/Unit/SDK/Logs/Exporter/ConsoleExporterFactoryTest.php
index 0d8625132..fd7970948 100644
--- a/tests/Unit/SDK/Logs/Exporter/ConsoleExporterFactoryTest.php
+++ b/tests/Unit/SDK/Logs/Exporter/ConsoleExporterFactoryTest.php
@@ -18,4 +18,16 @@ public function test_create(): void
 
         $this->assertInstanceOf(ConsoleExporter::class, $factory->create());
     }
+
+    public function test_type(): void
+    {
+        $factory = new ConsoleExporterFactory();
+        $this->assertSame('console', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new ConsoleExporterFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/SDK/Logs/Exporter/InMemoryExporterFactoryTest.php b/tests/Unit/SDK/Logs/Exporter/InMemoryExporterFactoryTest.php
index 6150049bb..18d8bd5cb 100644
--- a/tests/Unit/SDK/Logs/Exporter/InMemoryExporterFactoryTest.php
+++ b/tests/Unit/SDK/Logs/Exporter/InMemoryExporterFactoryTest.php
@@ -17,4 +17,15 @@ public function test_create(): void
         $factory = new InMemoryExporterFactory();
         $this->assertInstanceOf(LogRecordExporterInterface::class, $factory->create());
     }
+    public function test_type(): void
+    {
+        $factory = new InMemoryExporterFactory();
+        $this->assertSame('memory', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new InMemoryExporterFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/SDK/Metrics/MetricExporter/ConsoleMetricExporterFactoryTest.php b/tests/Unit/SDK/Metrics/MetricExporter/ConsoleMetricExporterFactoryTest.php
index 5087e2044..4148d89f1 100644
--- a/tests/Unit/SDK/Metrics/MetricExporter/ConsoleMetricExporterFactoryTest.php
+++ b/tests/Unit/SDK/Metrics/MetricExporter/ConsoleMetricExporterFactoryTest.php
@@ -17,4 +17,16 @@ public function test_create(): void
         $exporter = (new ConsoleMetricExporterFactory())->create();
         $this->assertInstanceOf(MetricExporterInterface::class, $exporter);
     }
+
+    public function test_type(): void
+    {
+        $factory = new ConsoleMetricExporterFactory();
+        $this->assertSame('console', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new ConsoleMetricExporterFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/SDK/Metrics/MetricExporter/InMemoryExporterFactoryTest.php b/tests/Unit/SDK/Metrics/MetricExporter/InMemoryExporterFactoryTest.php
index dac703047..5a64e99e3 100644
--- a/tests/Unit/SDK/Metrics/MetricExporter/InMemoryExporterFactoryTest.php
+++ b/tests/Unit/SDK/Metrics/MetricExporter/InMemoryExporterFactoryTest.php
@@ -17,4 +17,16 @@ public function test_create(): void
         $exporter = (new InMemoryExporterFactory())->create();
         $this->assertInstanceOf(MetricExporterInterface::class, $exporter);
     }
+
+    public function test_type(): void
+    {
+        $factory = new InMemoryExporterFactory();
+        $this->assertSame('memory', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new InMemoryExporterFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/SDK/Metrics/MetricExporter/NoopMetricExporterFactoryTest.php b/tests/Unit/SDK/Metrics/MetricExporter/NoopMetricExporterFactoryTest.php
index d928a5887..1dd26282f 100644
--- a/tests/Unit/SDK/Metrics/MetricExporter/NoopMetricExporterFactoryTest.php
+++ b/tests/Unit/SDK/Metrics/MetricExporter/NoopMetricExporterFactoryTest.php
@@ -17,4 +17,16 @@ public function test_create(): void
         $exporter = (new NoopMetricExporterFactory())->create();
         $this->assertInstanceOf(MetricExporterInterface::class, $exporter);
     }
+
+    public function test_type(): void
+    {
+        $factory = new NoopMetricExporterFactory();
+        $this->assertSame('none', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new NoopMetricExporterFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/SDK/Resource/ResourceInfoFactoryTest.php b/tests/Unit/SDK/Resource/ResourceInfoFactoryTest.php
index bb4d6a80e..2f30e2599 100644
--- a/tests/Unit/SDK/Resource/ResourceInfoFactoryTest.php
+++ b/tests/Unit/SDK/Resource/ResourceInfoFactoryTest.php
@@ -9,8 +9,6 @@
 use OpenTelemetry\API\Behavior\Internal\Logging;
 use OpenTelemetry\API\Behavior\Internal\LogWriter\LogWriterInterface;
 use OpenTelemetry\SDK\Common\Attribute\Attributes;
-use OpenTelemetry\SDK\Registry;
-use OpenTelemetry\SDK\Resource\ResourceDetectorInterface;
 use OpenTelemetry\SDK\Resource\ResourceInfo;
 use OpenTelemetry\SDK\Resource\ResourceInfoFactory;
 use OpenTelemetry\Tests\TestState;
@@ -120,36 +118,22 @@ public function test_resource_from_environment_resource_attribute_takes_preceden
         $this->assertEquals('foo', $resource->getAttributes()->get('service.name'));
     }
 
-    public function test_resource_from_registry(): void
-    {
-        $this->setEnvironmentVariable('OTEL_PHP_DETECTORS', 'foo');
-        $detector = $this->createMock(ResourceDetectorInterface::class);
-        $detector->expects($this->once())->method('getResource')->willReturn($this->createMock(ResourceInfo::class));
-
-        Registry::registerResourceDetector('foo', $detector);
-        ResourceInfoFactory::defaultResource();
-    }
-
-    public function test_all_resources_uses_extra_resource_from_registry(): void
+    public function test_all_resources_uses_extra_resource_from_spi(): void
     {
         $this->setEnvironmentVariable('OTEL_PHP_DETECTORS', 'all');
-        $detector = $this->createMock(ResourceDetectorInterface::class);
-        $resource = $this->createMock(ResourceInfo::class);
-        $detector->expects($this->once())->method('getResource')->willReturn($resource);
 
-        Registry::registerResourceDetector('foo', $detector);
-        ResourceInfoFactory::defaultResource();
+        $resource = ResourceInfoFactory::defaultResource();
+        $this->assertTrue($resource->getAttributes()->has('test-resource'));
+        $this->assertSame('test-value', $resource->getAttributes()->get('test-resource'));
     }
 
-    public function test_composite_default_with_extra_resource_from_registry(): void
+    public function test_composite_default_with_extra_resource_from_spi(): void
     {
-        $this->setEnvironmentVariable('OTEL_PHP_DETECTORS', 'foo,env');
-        $resource = $this->createMock(ResourceInfo::class);
-        $detector = $this->createMock(ResourceDetectorInterface::class);
-        $detector->expects($this->once())->method('getResource')->willReturn($resource);
+        $this->setEnvironmentVariable('OTEL_PHP_DETECTORS', 'test,sdk');
+        $resource = ResourceInfoFactory::defaultResource();
 
-        Registry::registerResourceDetector('foo', $detector);
-        ResourceInfoFactory::defaultResource();
+        $this->assertTrue($resource->getAttributes()->has('test-resource'));
+        $this->assertTrue($resource->getAttributes()->has('telemetry.sdk.language'));
     }
 
     public function test_default_with_all_sdk_detectors(): void
diff --git a/tests/Unit/SDK/Trace/SpanExporter/ConsoleSpanExporterFactoryTest.php b/tests/Unit/SDK/Trace/SpanExporter/ConsoleSpanExporterFactoryTest.php
index 280d44c1f..002e6b582 100644
--- a/tests/Unit/SDK/Trace/SpanExporter/ConsoleSpanExporterFactoryTest.php
+++ b/tests/Unit/SDK/Trace/SpanExporter/ConsoleSpanExporterFactoryTest.php
@@ -17,4 +17,16 @@ public function test_create(): void
         $exporter = (new ConsoleSpanExporterFactory())->create();
         $this->assertInstanceOf(SpanExporterInterface::class, $exporter);
     }
+
+    public function test_type(): void
+    {
+        $factory = new ConsoleSpanExporterFactory();
+        $this->assertSame('console', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new ConsoleSpanExporterFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/Unit/SDK/Trace/SpanExporter/InMemorySpanExporterFactoryTest.php b/tests/Unit/SDK/Trace/SpanExporter/InMemorySpanExporterFactoryTest.php
index dec657b28..6e6cf58de 100644
--- a/tests/Unit/SDK/Trace/SpanExporter/InMemorySpanExporterFactoryTest.php
+++ b/tests/Unit/SDK/Trace/SpanExporter/InMemorySpanExporterFactoryTest.php
@@ -17,4 +17,16 @@ public function test_create(): void
         $exporter = (new InMemorySpanExporterFactory())->create();
         $this->assertInstanceOf(SpanExporterInterface::class, $exporter);
     }
+
+    public function test_type(): void
+    {
+        $factory = new InMemorySpanExporterFactory();
+        $this->assertSame('memory', $factory->type());
+    }
+
+    public function test_priority(): void
+    {
+        $factory = new InMemorySpanExporterFactory();
+        $this->assertSame(0, $factory->priority());
+    }
 }
diff --git a/tests/_register.php b/tests/_register.php
new file mode 100644
index 000000000..0bc55e402
--- /dev/null
+++ b/tests/_register.php
@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+use Nevay\SPI\ServiceLoader;
+use OpenTelemetry\Config\SDK\Configuration\ComponentProvider;
+use OpenTelemetry\Example\ExampleConfigProvider;
+use OpenTelemetry\Tests\Integration\Config\ComponentProvider\Metrics\AggregationResolverExplicitBucketHistogram;
+use OpenTelemetry\Tests\Integration\Config\ComponentProvider\Metrics\MetricExporterPrometheus;
+use OpenTelemetry\Tests\Integration\Config\ComponentProvider\Metrics\MetricReaderPull;
+use OpenTelemetry\Tests\Integration\Config\ComponentProvider\Propagator\TextMapPropagatorOtTrace;
+use OpenTelemetry\Tests\Integration\Config\ComponentProvider\Propagator\TextMapPropagatorXray;
+
+ServiceLoader::register(ComponentProvider::class, ExampleConfigProvider::class);
+ServiceLoader::register(ComponentProvider::class, AggregationResolverExplicitBucketHistogram::class);
+ServiceLoader::register(ComponentProvider::class, MetricExporterPrometheus::class);
+ServiceLoader::register(ComponentProvider::class, MetricReaderPull::class);
+ServiceLoader::register(ComponentProvider::class, TextMapPropagatorXray::class);
+ServiceLoader::register(ComponentProvider::class, TextMapPropagatorOtTrace::class);
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
index 6408be93a..7f505c7e3 100644
--- a/tests/bootstrap.php
+++ b/tests/bootstrap.php
@@ -6,4 +6,4 @@
 
 require_once __DIR__ . '/../vendor/autoload.php';
 
-BypassFinals::enable();
+BypassFinals::enable(bypassReadOnly: false);