You can modify the container here before it is dumped to PHP code.

@param ContainerBuilder $container

@api
14660
public function process(ContainerBuilder $container)
    {
        $this->setServiceAlias( $container, HeliopsisEzFormsExtension::FACADE_SERVICE_ID );
        $this->setServiceAlias( $container, HeliopsisEzFormsExtension::FORM_PROVIDER_SERVICE_ID );
        $this->setServiceAlias( $container, HeliopsisEzFormsExtension::HANDLER_PROVIDER_SERVICE_ID );
        $this->setServiceAlias( $container, HeliopsisEzFormsExtension::RESPONSE_PROVIDER_SERVICE_ID );
    }
684112
public function process(ContainerBuilder $container)
    {
        if ($container->hasDefinition($this->loggerTag)) {
            $logger = new Reference($this->loggerTag);

            $reportBugCommandDefinition = $container->getDefinition(ReportBugCommand::class);
            $reportBugCommandDefinition->addMethodCall('setLogger', [$logger]);
        }
    }
158242
public function process(ContainerBuilder $container)
    {
        if (!$container->hasDefinition('stack_factory')) {
            return;
        }

        $stackFactory = $container->getDefinition('stack_factory');
        $stackPriority = [];

        foreach ($container->findTaggedServiceIds('stack_middleware') as $id => $attributes) {
            $priority = isset($attributes[0]['priority']) ? $attributes[0]['priority'] : 0;
            $stackPriority[$priority][] = $this->retrieveArguments($container, $id);
        }

        if (false === empty($stackPriority)) {
            $this->addMiddlewares($stackFactory, $stackPriority);
        }
    }
6099
public function process(ContainerBuilder $container)
    {
        if (!$container->hasDefinition(TaggedServices::class)) {
            return;
        }

        $manager = $container->getDefinition(TaggedServices::class);

        $definitions = $container->getDefinitions();
        foreach ($definitions as $id => $definition) {
            foreach ($definition->getTags() as $tagName => $tagAttributes) {
                $manager->addMethodCall(
                    'addSpecification',
                    [$id, $tagName, $tagAttributes[0]]
                );
            }
        }
    }
26343
public function build(ContainerBuilder $container)
    {
        $container->addCompilerPass(new CommandProcessorPass(), PassConfig::TYPE_BEFORE_REMOVING);
        $container->addCompilerPass(new PoolsPass());
        $container->addCompilerPass(new RegisterSerializerDriversPass());
        $container->addCompilerPass(new WorkerRunnersPass());
    }
1368332
public function process(ContainerBuilder $container)
    {
        $def = $container->getDefinition('zicht_admin.event_propagator');

        foreach ($container->findTaggedServiceIds('zicht_admin.event_propagation') as $id => $attributes) {
            foreach ($attributes as $attribute) {
                $def->addTag('kernel.event_listener', array('event' => $attribute['event'], 'method' => 'onEvent'));
                $def->addMethodCall('registerPropagation', array($attribute['event'], new Reference($id)));
            }
        }
    }
345437
public function process(ContainerBuilder $container)
    {
        $this->container = $container;

        foreach ($container->getDefinitions() as $definition) {
            if ($definition->isSynthetic() || $definition->isAbstract()) {
                continue;
            }

            $definition->setArguments($this->processArguments($definition->getArguments()));
            $definition->setMethodCalls($this->processArguments($definition->getMethodCalls()));
            $definition->setProperties($this->processArguments($definition->getProperties()));
            $definition->setFactory($this->processFactory($definition->getFactory()));
        }

        foreach ($container->getAliases() as $id => $alias) {
            $aliasId = (string) $alias;
            if ($aliasId !== $defId = $this->getDefinitionId($aliasId)) {
                $container->setAlias($id, new Alias($defId, $alias->isPublic()));
            }
        }
    }
291205
public function process(ContainerBuilder $container)
    {
        if (!$container->has($this->getCollectorServiceName())) {
            return;
        }

        $definition = $container->findDefinition(
            $this->getCollectorServiceName()
        );

        $taggedServices = $container->findTaggedServiceIds(
            $this->getTagName()
        );
        foreach ($taggedServices as $id => $tags) {
            $definition->addMethodCall(
                $this->getCollectorMethodName(),
                [new Reference($id)]
            );
        }
    }
653685
public function prepend(ContainerBuilder $container)
    {
        $configs = $container->getExtensionConfig($this->getAlias());
        $config = $this->processConfiguration(new Configuration(), $configs);

        $bundles = $container->getParameter('kernel.bundles');

        // Publish assetic assets if desired
        if ($config['assets']['publish'] && isset($bundles['AsseticBundle'])) {
            $container->prependExtensionConfig('assetic', array('assets' => $this->getAssets($config)));
        }
    }
698083
public function process(ContainerBuilder $container)
    {
        do {
            $this->repeat = false;
            foreach ($this->passes as $pass) {
                $pass->process($container);
            }
        } while ($this->repeat);
    }
777066
public function process(ContainerBuilder $container)
    {
        if (!$container->hasDefinition($this->subjectService)) {
            return;
        }

        $subjects = $this->findTaggedServices($container, $this->subjectTag, SubjectInterface::class, 'support', false);

        $subjectDefinition = $container->getDefinition($this->subjectService);
        $subjectDefinition->replaceArgument(0, $subjects);
    }
967242
public function prepend(ContainerBuilder $container): void
    {
        $loader = new XmlFileLoader($container, new FileLocator(__DIR__ . '/../Resources/config'));

        $this->prependTwig($container, $loader);
    }
596920
public function process(ContainerBuilder $container)
    {
        foreach ($container->findTaggedServiceIds($this->baseTag) as $id => $services) {
            foreach ((array) $services as $service) {
                $this->findAndReplaceTaggedServices($id, $service, $container);
            }
        }
    }
294609
public function loadServices(ContainerBuilder $container)
    {
        $loader = new XmlFileLoader($container, new FileLocator(__DIR__ . '/config'));
        $loader->load('services.xml');
        $this->imageDrivers = $this->driverLocator->findDrivers(
            $container,
            $this->imageDriverKeys,
            $this->imageDriverConfigs
        );
    }
588382
public function process(ContainerBuilder $container): void
    {
        $container->setParameter('service_bus.logger.echo.log_level', $this->logLevel);

        $container->addDefinitions(
            [
                StdOutHandler::class => (new Definition(StdOutHandler::class))->setArguments(['%service_bus.logger.echo.log_level%']),
            ]
        );

        (new LoggerCompilerPass())->process($container);

        $loggerDefinition = $container->getDefinition('service_bus.logger');

        $loggerDefinition->addMethodCall(
            'pushHandler',
            [new Reference(StdOutHandler::class)]
        );
    }
739713
public function process(ContainerBuilder $container)
    {
        $this->setFactoryAndServerClasses($container);
        parent::process($container);
        $this->setCasServerConfig($container);
    }
340604
public function build(ContainerBuilder $container)
    {
        parent::build($container);

        $container->addCompilerPass(new VersionCompilerPass(new PrettyVersions()));
        $container->addCompilerPass(new EnvParametersCompilerPass());
        $container->addCompilerPass(new RouteLoaderCompilerPass());
        $container->addCompilerPass(new HttpClientOptionsCompilerPass());
    }