# For developers Powermail can be extended in similar ways. If you want to execute something on a submit, look at the Finisher Classes. If you want to add own spamshield methods, look in this chapter, etc... * [AddFinisherClasses](/ForDevelopers/AddFinisherClasses.md) * [AddSpamshieldMethods](/ForDevelopers/AddSpamshieldMethods.md) * [DisableSpamshield](/ForDevelopers/DisableSpamshield.md) * [EventDispatcher](/ForDevelopers/EventDispatcher.md) * [AddNewFields](/ForDevelopers/AddNewFields.md) * [AddNewFieldProperties](/ForDevelopers/AddNewFieldProperties.md) * [AddNewFlexFormProperties](/ForDevelopers/AddNewFlexFormProperties.md) * [WriteOwnValidators](/ForDevelopers/WriteOwnValidators.md) * [AddDataProcessors](/ForDevelopers/AddDataProcessors.md) * [UserfuncsWithCobject](/ForDevelopers/UserfuncsWithCobject.md) * [DatabaseModel](/ForDevelopers/DatabaseModel.md) * [Local Development with Docker](/ForDevelopers/LocalDevelopment.md)