TYPO3.Flow

currently, Core\Booting\Sequence::invokeStep() looks

1$bootstrap->getSignalSlotDispatcher()->dispatch(__CLASS__, 'beforeInvokeStep', array($step));
2$identifier = $step->getIdentifier();
3$step($bootstrap);
4$bootstrap->getSignalSlotDispatcher()->dispatch(__CLASS__, 'afterInvokeStep', array($step));

This requires listening to a specific step invocation to look like this (taken from an example):

1$dispatcher->connect('TYPO3\FLOW3\Core\Booting\Sequence', 'afterInvokeStep', function(\TYPO3\FLOW3\Core\Booting\Step $step) use ($bootstrap) {
2    if ($step->getIdentifier() === 'typo3.flow3:objectmanagement:compiletime:create') {
3        $bootstrap->getObjectManager()->get('....');
4    }
5});

Due to the fact that, I claim, invoke-step-listening surely always intends to affect a specific step, I suggest to involve additional "magic" signals that take their name from the step identifier, resulting in, for example,

1$dispatcher->connect('TYPO3\FLOW3\Core\Booting\Sequence', 'afterInvokeStepTypo3Flow3ObjectmanagementCompiletimeCreate', function(\TYPO3\FLOW3\Core\Booting\Step $step) use ($bootstrap) {
2    $bootstrap->getObjectManager()->get('....');
3});