Services that are not intended for decoration or direct use must be marked with
@internal and have an appropriate comment in the docblock why they should not be used or decorated directly.
Classes marked with
@internal need not be kept compatible for third-party developers. Here the public api can change at any time.
__construct methods of services instantiated via DI container are not public API and can be changed at any time
__construct functions of Data Transfer Objects (DTO), which could therefore be instantiated by the developer himself (e.g.
QuantityPriceDefinition), are public API and must be kept backward compatible