feat(plugin): run plugin-provided commands in a worker-side application

A same-FQCN Composer\Console\Application, hand-written under the new
php/runtime/ tree, hosts CommandProvider commands inside the PHP worker:
PhpCommandProxy overrides run() and forwards the stringified input, so the
real Symfony machinery binds, validates and executes against the live
command object, while help/list render Rust-side from a definition read
back at construction. Reverse \Shirabe\RustCommandStub rows let a plugin
command invoke built-in commands back in the Rust process, keeping every
command on the side whose helper set it was written for.

Composer\EventDispatcher\Event moves from a generated stub to a dual-mode
runtime class: the real BaseCommand::initialize constructs a
PreCommandRunEvent natively in the worker, which a proxy-only constructor
guard rejected. Its PRE_COMMAND_RUN dispatch reaches a new EventDispatcher
stub whose dispatch supports the observably-no-op no-listener case and
fails explicitly otherwise. The stub generator now accepts runtime-provided
classes as stub bases (never as targets) and cross-checks the Application
handoff property table against the real class.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

7 files changed, 476 insertions, 73 deletions

diff --git a/crates/shirabe-php-rpc/php/runtime/Composer/Console/Application.php b/crates/shirabe-php-rpc/php/runtime/Composer/Console/Application.php
new file mode 100644
index 00000000..50ea31b1
--- /dev/null
+++ b/crates/shirabe-php-rpc/php/runtime/Composer/Console/Application.php
@@ -0,0 +1,142 @@
+<?php
+
+// Shirabe's own definition of Composer\Console\Application for the plugin worker. The real
+// class file is never autoloaded in this process: plugin-provided commands run here under a
+// genuine Symfony console application, and this class supplies the Composer-specific surface
+// (getIO()/getComposer()/...) backed by the Rust process over RPC. Defining the same FQCN
+// instead of subclassing the real class keeps both `instanceof` and strict `get_class()`
+// comparisons identical to upstream.
+//
+// Unlike the files under stubs/, the classes under runtime/ are hand-written: they are
+// two-world implementations with behavior of their own, not mechanical proxies, so the stub
+// generator does not manage them.
+
+namespace Composer\Console;
+
+use Composer\Composer;
+use Composer\IO\IOInterface;
+use Symfony\Component\Console\Application as BaseApplication;
+use Symfony\Component\Console\Input\InputDefinition;
+use Symfony\Component\Console\Input\InputOption;
+
+class Application extends BaseApplication
+{
+    private static bool $shirabeConstructing = false;
+
+    /** @var Composer|null */
+    private $shirabeComposer = null;
+    /** @var IOInterface */
+    private $shirabeIo;
+    /** @var string|null */
+    private $shirabeInitialWorkingDirectory = null;
+    private bool $shirabeDisablePluginsByDefault = false;
+    private bool $shirabeDisableScriptsByDefault = false;
+
+    /**
+     * Builds the worker-side application from the Rust-side handoff. $config keys:
+     * `composer` (Composer proxy stub or null), `io` (IO proxy stub),
+     * `initialWorkingDirectory` (?string), `disablePluginsByDefault` (bool),
+     * `disableScriptsByDefault` (bool), `rustCommands` (metadata rows for
+     * \Shirabe\RustCommandStub), `pluginCommands` (live command entities from the P table).
+     */
+    public static function __shirabeBoot(array $config): self
+    {
+        self::$shirabeConstructing = true;
+        try {
+            $app = new self();
+        } finally {
+            self::$shirabeConstructing = false;
+        }
+        $app->setAutoExit(false);
+        // A command failure must reach the Rust side as an RPC throw, not get rendered here.
+        $app->setCatchExceptions(false);
+        $app->shirabeComposer = $config['composer'];
+        $app->shirabeIo = $config['io'];
+        $app->shirabeInitialWorkingDirectory = $config['initialWorkingDirectory'];
+        $app->shirabeDisablePluginsByDefault = $config['disablePluginsByDefault'];
+        $app->shirabeDisableScriptsByDefault = $config['disableScriptsByDefault'];
+        foreach ($config['rustCommands'] as $meta) {
+            $app->add(new \Shirabe\RustCommandStub($meta));
+        }
+        foreach ($config['pluginCommands'] as $command) {
+            $app->add($command);
+        }
+
+        return $app;
+    }
+
+    public function __construct(string $name = 'Composer', string $version = '')
+    {
+        if (!self::$shirabeConstructing) {
+            // TODO(plugin): a plugin constructing its own Composer\Console\Application would
+            // run commands outside the Rust-side orchestration; whether and how to support
+            // that is undecided, so fail loudly instead of handing out a half-wired instance.
+            throw new \RuntimeException(
+                'Shirabe does not support constructing Composer\Console\Application inside the plugin process yet'
+            );
+        }
+        parent::__construct($name, $version !== '' ? $version : Composer::getVersion());
+    }
+
+    public function getIO(): IOInterface
+    {
+        return $this->shirabeIo;
+    }
+
+    public function getComposer(bool $required = true, ?bool $disablePlugins = null, ?bool $disableScripts = null): ?Composer
+    {
+        if (null === $this->shirabeComposer && $required) {
+            // TODO(plugin): creating a Composer instance from scratch here would need
+            // Factory::create over RPC; the handoff currently always carries the instance the
+            // Rust side already built, so this only fires after resetComposer-style flows.
+            throw new \RuntimeException(
+                'Shirabe cannot create a new Composer instance inside the plugin process yet'
+            );
+        }
+
+        return $this->shirabeComposer;
+    }
+
+    public function resetComposer(): void
+    {
+        // TODO(plugin): the Composer instance is owned by the Rust process; dropping only the
+        // worker-side reference would desynchronize the two worlds, so this needs a
+        // reset-and-refetch round trip that does not exist yet.
+        throw new \RuntimeException(
+            'Shirabe does not support resetComposer() inside the plugin process yet'
+        );
+    }
+
+    /**
+     * @return string|null
+     */
+    public function getInitialWorkingDirectory()
+    {
+        return $this->shirabeInitialWorkingDirectory;
+    }
+
+    public function getDisablePluginsByDefault(): bool
+    {
+        return $this->shirabeDisablePluginsByDefault;
+    }
+
+    public function getDisableScriptsByDefault(): bool
+    {
+        return $this->shirabeDisableScriptsByDefault;
+    }
+
+    // Same as the real class: without Composer's global options in the definition, binding a
+    // forwarded command line that carries e.g. --working-dir would fail here even though the
+    // Rust side already consumed the option.
+    protected function getDefaultInputDefinition(): InputDefinition
+    {
+        $definition = parent::getDefaultInputDefinition();
+        $definition->addOption(new InputOption('--profile', null, InputOption::VALUE_NONE, 'Display timing and memory usage information'));
+        $definition->addOption(new InputOption('--no-plugins', null, InputOption::VALUE_NONE, 'Whether to disable plugins.'));
+        $definition->addOption(new InputOption('--no-scripts', null, InputOption::VALUE_NONE, 'Skips the execution of all scripts defined in composer.json file.'));
+        $definition->addOption(new InputOption('--working-dir', '-d', InputOption::VALUE_REQUIRED, 'If specified, use the given directory as working directory.'));
+        $definition->addOption(new InputOption('--no-cache', null, InputOption::VALUE_NONE, 'Prevent use of the cache'));
+
+        return $definition;
+    }
+}
diff --git a/crates/shirabe-php-rpc/php/runtime/Composer/EventDispatcher/Event.php b/crates/shirabe-php-rpc/php/runtime/Composer/EventDispatcher/Event.php
new file mode 100644
index 00000000..0d35ac55
--- /dev/null
+++ b/crates/shirabe-php-rpc/php/runtime/Composer/EventDispatcher/Event.php
@@ -0,0 +1,120 @@
+<?php
+
+// Shirabe's own definition of Composer\EventDispatcher\Event for the plugin worker. This class
+// lives in both worlds at once: an instance revived from a Rust handle proxies every call over
+// RPC (like a generated stub), while an instance constructed natively — real Composer code in
+// this process does `new PreCommandRunEvent(...)`, whose parent constructor lands here — is a
+// faithful in-process port of the real base class. The two modes are told apart by the
+// constructor arguments; `__shirabeRustHandleDescriptor()` returns null in native mode so the
+// wire codec registers the object in the P table instead of treating it as a Rust handle.
+
+namespace Composer\EventDispatcher;
+
+class Event implements \ShirabeRustStub
+{
+    /** @var int|null Null in native mode. */
+    protected $__rhandle;
+    /** @var int */
+    protected $__epoch = 0;
+
+    /** @var string This event's name (native mode) */
+    protected $name;
+
+    /** @var string[] Arguments passed by the user, these will be forwarded to CLI script handlers (native mode) */
+    protected $args;
+
+    /** @var mixed[] Flags usable in PHP script handlers (native mode) */
+    protected $flags;
+
+    /** @var bool Whether the event should not be passed to more listeners (native mode) */
+    private $propagationStopped = false;
+
+    /**
+     * Proxy revival passes (int $rhandle, int $epoch); the real class's constructor is
+     * (string $name, array $args = [], array $flags = []).
+     */
+    public function __construct($name = null, $args = [], $flags = [])
+    {
+        if (is_int($name) && func_num_args() === 2 && is_int($args)) {
+            $this->__rhandle = $name;
+            $this->__epoch = $args;
+
+            return;
+        }
+        if (!is_string($name)) {
+            throw new \RuntimeException(
+                'Shirabe does not support constructing ' . static::class . ' inside the plugin process without an event name'
+            );
+        }
+        $this->__rhandle = null;
+        $this->name = $name;
+        $this->args = $args;
+        $this->flags = $flags;
+    }
+
+    public function __destruct()
+    {
+        if ($this->__rhandle !== null) {
+            \ShirabeRustObjectRegistry::release($this->__rhandle);
+        }
+    }
+
+    public function __shirabeRustHandleDescriptor(): ?array
+    {
+        if ($this->__rhandle === null) {
+            return null;
+        }
+
+        return [
+            '__rhandle' => $this->__rhandle,
+            '__class' => static::class,
+            '__epoch' => $this->__epoch,
+        ];
+    }
+
+    public function getName(): string
+    {
+        if ($this->__rhandle !== null) {
+            return \ShirabeRpcRuntime::callRust($this->__rhandle, 'getName', []);
+        }
+
+        return $this->name;
+    }
+
+    public function getArguments(): array
+    {
+        if ($this->__rhandle !== null) {
+            return \ShirabeRpcRuntime::callRust($this->__rhandle, 'getArguments', []);
+        }
+
+        return $this->args;
+    }
+
+    public function getFlags(): array
+    {
+        if ($this->__rhandle !== null) {
+            return \ShirabeRpcRuntime::callRust($this->__rhandle, 'getFlags', []);
+        }
+
+        return $this->flags;
+    }
+
+    public function isPropagationStopped(): bool
+    {
+        if ($this->__rhandle !== null) {
+            return \ShirabeRpcRuntime::callRust($this->__rhandle, 'isPropagationStopped', []);
+        }
+
+        return $this->propagationStopped;
+    }
+
+    public function stopPropagation(): void
+    {
+        if ($this->__rhandle !== null) {
+            \ShirabeRpcRuntime::callRust($this->__rhandle, 'stopPropagation', []);
+
+            return;
+        }
+        $this->propagationStopped = true;
+    }
+}
diff --git a/crates/shirabe-php-rpc/php/runtime/Shirabe/RustCommandStub.php b/crates/shirabe-php-rpc/php/runtime/Shirabe/RustCommandStub.php
new file mode 100644
index 00000000..23ebfc04
--- /dev/null
+++ b/crates/shirabe-php-rpc/php/runtime/Shirabe/RustCommandStub.php
@@ -0,0 +1,34 @@
+<?php
+
+// Worker-side stand-in for a Rust-implemented (built-in) command: it carries only the list
+// metadata, and running it forwards the raw input line back to the Rust process, where the
+// real implementation executes against its own application state (helper set included). This
+// is how a plugin command that invokes a built-in command crosses back over the process
+// boundary; each command always runs on the side that owns its implementation, so a helper
+// lookup always resolves against the helper set of the world the command was written for.
+
+namespace Shirabe;
+
+use Composer\Command\BaseCommand;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+class RustCommandStub extends BaseCommand
+{
+    /** @param array{name: string, description: string, aliases: list<string>, hidden: bool} $meta */
+    public function __construct(array $meta)
+    {
+        parent::__construct($meta['name']);
+        $this->setDescription($meta['description']);
+        $this->setAliases($meta['aliases']);
+        $this->setHidden($meta['hidden']);
+        // The real input definition lives on the Rust side and the raw tokens are forwarded
+        // untouched, so nothing may be validated (or consumed) here.
+        $this->ignoreValidationErrors();
+    }
+
+    public function run(InputInterface $input, OutputInterface $output): int
+    {
+        return (int) \ShirabeRpcRuntime::callRust(0, '__shirabe_run_rust_command', [$this->getName(), (string) $input]);
+    }
+}
diff --git a/crates/shirabe-php-rpc/php/stubs/Composer/EventDispatcher/Event.php b/crates/shirabe-php-rpc/php/stubs/Composer/EventDispatcher/Event.php
deleted file mode 100644
index fea84c75..00000000
--- a/crates/shirabe-php-rpc/php/stubs/Composer/EventDispatcher/Event.php
+++ /dev/null
@@ -1,67 +0,0 @@
-<?php
-
-// Generated by scripts/plugin-stub-generator; do not edit by hand.
-// Proxy stub for Composer\EventDispatcher\Event: the public surface forwards to the Rust-side entity over RPC.
-
-namespace Composer\EventDispatcher;
-
-class Event implements \ShirabeRustStub
-{
-    /** @var int */
-    protected $__rhandle;
-    /** @var int */
-    protected $__epoch;
-
-    public function __construct(int $rhandle = 0, int $epoch = 0)
-    {
-        if (func_num_args() < 2) {
-            // Constructing the class from plugin code (a common idiom for e.g. `new BufferIO()`)
-            // is an open question of the plugin design; only proxy instantiation passes a
-            // Rust handle. Fail with a diagnosable message instead of an ArgumentCountError.
-            throw new \RuntimeException(
-                'Shirabe does not support constructing ' . static::class . ' inside the plugin process yet'
-            );
-        }
-        $this->__rhandle = $rhandle;
-        $this->__epoch = $epoch;
-    }
-
-    public function __destruct()
-    {
-        \ShirabeRustObjectRegistry::release($this->__rhandle);
-    }
-
-    public function __shirabeRustHandleDescriptor(): array
-    {
-        return [
-            '__rhandle' => $this->__rhandle,
-            '__class' => static::class,
-            '__epoch' => $this->__epoch,
-        ];
-    }
-
-    public function getName(): string
-    {
-        return \ShirabeRpcRuntime::callRust($this->__rhandle, 'getName', []);
-    }
-
-    public function getArguments(): array
-    {
-        return \ShirabeRpcRuntime::callRust($this->__rhandle, 'getArguments', []);
-    }
-
-    public function getFlags(): array
-    {
-        return \ShirabeRpcRuntime::callRust($this->__rhandle, 'getFlags', []);
-    }
-
-    public function isPropagationStopped(): bool
-    {
-        return \ShirabeRpcRuntime::callRust($this->__rhandle, 'isPropagationStopped', []);
-    }
-
-    public function stopPropagation(): void
-    {
-        \ShirabeRpcRuntime::callRust($this->__rhandle, 'stopPropagation', []);
-    }
-}
diff --git a/crates/shirabe-php-rpc/php/stubs/Composer/EventDispatcher/EventDispatcher.php b/crates/shirabe-php-rpc/php/stubs/Composer/EventDispatcher/EventDispatcher.php
new file mode 100644
index 00000000..c0651081
--- /dev/null
+++ b/crates/shirabe-php-rpc/php/stubs/Composer/EventDispatcher/EventDispatcher.php
@@ -0,0 +1,92 @@
+<?php
+
+// Generated by scripts/plugin-stub-generator; do not edit by hand.
+// Proxy stub for Composer\EventDispatcher\EventDispatcher: the public surface forwards to the Rust-side entity over RPC.
+
+namespace Composer\EventDispatcher;
+
+use Composer\DependencyResolver\Transaction;
+use Composer\DependencyResolver\Operation\OperationInterface;
+use Composer\Repository\RepositoryInterface;
+
+class EventDispatcher implements \ShirabeRustStub
+{
+    /** @var int */
+    protected $__rhandle;
+    /** @var int */
+    protected $__epoch;
+
+    public function __construct(int $rhandle = 0, int $epoch = 0)
+    {
+        if (func_num_args() < 2) {
+            // Constructing the class from plugin code (a common idiom for e.g. `new BufferIO()`)
+            // is an open question of the plugin design; only proxy instantiation passes a
+            // Rust handle. Fail with a diagnosable message instead of an ArgumentCountError.
+            throw new \RuntimeException(
+                'Shirabe does not support constructing ' . static::class . ' inside the plugin process yet'
+            );
+        }
+        $this->__rhandle = $rhandle;
+        $this->__epoch = $epoch;
+    }
+
+    public function __destruct()
+    {
+        \ShirabeRustObjectRegistry::release($this->__rhandle);
+    }
+
+    public function __shirabeRustHandleDescriptor(): array
+    {
+        return [
+            '__rhandle' => $this->__rhandle,
+            '__class' => static::class,
+            '__epoch' => $this->__epoch,
+        ];
+    }
+
+    public function setRunScripts(bool $runScripts = true): self
+    {
+        \ShirabeRpcRuntime::callRust($this->__rhandle, 'setRunScripts', [$runScripts]);
+        return $this;
+    }
+
+    public function dispatch(?string $eventName, ?Event $event = null): int
+    {
+        return \ShirabeRpcRuntime::callRust($this->__rhandle, 'dispatch', [$eventName, $event]);
+    }
+
+    public function dispatchScript(string $eventName, bool $devMode = false, array $additionalArgs = [], array $flags = []): int
+    {
+        return \ShirabeRpcRuntime::callRust($this->__rhandle, 'dispatchScript', [$eventName, $devMode, $additionalArgs, $flags]);
+    }
+
+    public function dispatchPackageEvent(string $eventName, bool $devMode, RepositoryInterface $localRepo, array $operations, OperationInterface $operation): int
+    {
+        return \ShirabeRpcRuntime::callRust($this->__rhandle, 'dispatchPackageEvent', [$eventName, $devMode, $localRepo, $operations, $operation]);
+    }
+
+    public function dispatchInstallerEvent(string $eventName, bool $devMode, bool $executeOperations, Transaction $transaction): int
+    {
+        return \ShirabeRpcRuntime::callRust($this->__rhandle, 'dispatchInstallerEvent', [$eventName, $devMode, $executeOperations, $transaction]);
+    }
+
+    public function addListener(string $eventName, $listener, int $priority = 0): void
+    {
+        \ShirabeRpcRuntime::callRust($this->__rhandle, 'addListener', [$eventName, $listener, $priority]);
+    }
+
+    public function removeListener($listener): void
+    {
+        \ShirabeRpcRuntime::callRust($this->__rhandle, 'removeListener', [$listener]);
+    }
+
+    public function addSubscriber(EventSubscriberInterface $subscriber): void
+    {
+        \ShirabeRpcRuntime::callRust($this->__rhandle, 'addSubscriber', [$subscriber]);
+    }
+
+    public function hasEventListeners(Event $event): bool
+    {
+        return \ShirabeRpcRuntime::callRust($this->__rhandle, 'hasEventListeners', [$event]);
+    }
+}
diff --git a/crates/shirabe-php-rpc/php/worker.php b/crates/shirabe-php-rpc/php/worker.php
index 50e9ef76..241dad57 100644
--- a/crates/shirabe-php-rpc/php/worker.php
+++ b/crates/shirabe-php-rpc/php/worker.php
@@ -18,8 +18,13 @@ const SHIRABE_MAX_FRAME_LEN = 268435456; // 256 MiB, mirrored on the Rust side.
 /** Marker interface every Rust-proxy stub class implements. */
 interface ShirabeRustStub
 {
-    /** @return array{__rhandle: int, __class: string, __epoch: int} */
-    public function __shirabeRustHandleDescriptor(): array;
+    /**
+     * Null when this instance holds no Rust handle: a dual-mode class (see php/runtime/) that
+     * was constructed natively in this process crosses the wire as a P-table entity instead.
+     *
+     * @return ?array{__rhandle: int, __class: string, __epoch: int}
+     */
+    public function __shirabeRustHandleDescriptor(): ?array;
 }
 
 /** Interns proxy stubs so the same Rust handle always yields the same stub instance. */
@@ -199,7 +204,11 @@ final class ShirabeRpcRuntime
     public static function toWire($value)
     {
         if ($value instanceof ShirabeRustStub) {
-            return $value->__shirabeRustHandleDescriptor();
+            $descriptor = $value->__shirabeRustHandleDescriptor();
+            if ($descriptor !== null) {
+                return $descriptor;
+            }
+            // A natively-constructed dual-mode instance falls through to the P table below.
         }
         if (is_object($value)) {
             return ShirabePhpObjectRegistry::descriptor($value);
@@ -616,6 +625,61 @@ ShirabeRpcRuntime::$dispatch = [
         }
         return $obj->{$args[1]};
     },
+    // Builds the worker-side Composer\Console\Application (the runtime/ definition, not the
+    // real class) from the Rust handoff; the caller keeps the returned handle and runs
+    // plugin-provided commands through __shirabe_run_console_application.
+    '__shirabe_console_application_boot' => static function ($args) {
+        return \Composer\Console\Application::__shirabeBoot($args[0]);
+    },
+    // Runs one command line (the stringified input of the Rust-side run) through a booted
+    // worker-side application; output goes to the inherited stdio, the exit code returns
+    // over the wire, and a command failure propagates as an RPC throw (catchExceptions is
+    // off on the booted application).
+    '__shirabe_run_console_application' => static function ($args) {
+        [$app, $inputString] = $args;
+        if (!$app instanceof \Composer\Console\Application) {
+            throw new RuntimeException('__shirabe_run_console_application expects an application handle');
+        }
+        return $app->run(new \Symfony\Component\Console\Input\StringInput($inputString));
+    },
+    // Reads a command's input definition (plus help text and extra usages) as plain data, so
+    // the Rust side can mirror it for `help`/`list` rendering without executing anything.
+    '__shirabe_read_command_definition' => static function ($args) {
+        $command = $args[0];
+        if (!$command instanceof \Symfony\Component\Console\Command\Command) {
+            throw new RuntimeException('__shirabe_read_command_definition expects a command handle');
+        }
+        $definition = $command->getDefinition();
+        $arguments = [];
+        foreach ($definition->getArguments() as $argument) {
+            $arguments[] = [
+                'name' => $argument->getName(),
+                'required' => $argument->isRequired(),
+                'isArray' => $argument->isArray(),
+                'description' => $argument->getDescription(),
+                'default' => $argument->getDefault(),
+            ];
+        }
+        $options = [];
+        foreach ($definition->getOptions() as $option) {
+            $options[] = [
+                'name' => $option->getName(),
+                'shortcut' => $option->getShortcut(),
+                'acceptValue' => $option->acceptValue(),
+                'isValueRequired' => $option->isValueRequired(),
+                'isArray' => $option->isArray(),
+                'isNegatable' => $option->isNegatable(),
+                'description' => $option->getDescription(),
+                'default' => $option->getDefault(),
+            ];
+        }
+        return [
+            'arguments' => $arguments,
+            'options' => $options,
+            'help' => $command->getHelp(),
+            'usages' => $command->getUsages(),
+        ];
+    },
 ];
 
 ShirabeRpcRuntime::serveForever();
diff --git a/crates/shirabe-php-rpc/src/lib.rs b/crates/shirabe-php-rpc/src/lib.rs
index ba5443d2..ef11d542 100644
--- a/crates/shirabe-php-rpc/src/lib.rs
+++ b/crates/shirabe-php-rpc/src/lib.rs
@@ -563,8 +563,8 @@ const GLUE_SCRIPT: &str = include_str!("../php/worker.php");
 /// generator's `--check` mode verifies both the file contents and this list).
 const STUB_FILES: &[(&str, &str)] = &[
     (
-        "Composer/EventDispatcher/Event.php",
-        include_str!("../php/stubs/Composer/EventDispatcher/Event.php"),
+        "Composer/EventDispatcher/EventDispatcher.php",
+        include_str!("../php/stubs/Composer/EventDispatcher/EventDispatcher.php"),
     ),
     (
         "Composer/Script/Event.php",
@@ -640,6 +640,24 @@ const STUB_FILES: &[(&str, &str)] = &[
     ),
 ];
 
+/// Hand-written worker-side classes (two-world implementations with behavior of their own, not
+/// mechanical proxies), written into the same autoload directory as the generated stubs so the
+/// prepended stub autoloader resolves their FQCNs ahead of any real class file.
+const RUNTIME_FILES: &[(&str, &str)] = &[
+    (
+        "Composer/Console/Application.php",
+        include_str!("../php/runtime/Composer/Console/Application.php"),
+    ),
+    (
+        "Composer/EventDispatcher/Event.php",
+        include_str!("../php/runtime/Composer/EventDispatcher/Event.php"),
+    ),
+    (
+        "Shirabe/RustCommandStub.php",
+        include_str!("../php/runtime/Shirabe/RustCommandStub.php"),
+    ),
+];
+
 struct Worker {
     stream: UnixStream,
     // Also queried for its exit status when a socket read/write fails, to tell a dead worker
@@ -707,7 +725,7 @@ fn spawn_worker() -> anyhow::Result<Worker> {
     std::fs::write(&script_path, GLUE_SCRIPT)?;
 
     let stubs_dir = tempdir.path().join("stubs");
-    for (relative_path, contents) in STUB_FILES {
+    for (relative_path, contents) in STUB_FILES.iter().chain(RUNTIME_FILES) {
         let path = stubs_dir.join(relative_path);
         std::fs::create_dir_all(path.parent().expect("stub paths have a parent"))?;
         std::fs::write(&path, contents)?;