> For the complete documentation index, see [llms.txt](https://help.besmart.software/erpc/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.besmart.software/erpc/en-consultant-manual/castomization-ec-addons.md).

# Castomization (ec addons)

If the desired behaviour cannot be achieved using Pre/Post processes, an addon for EC can be programmed - the so-called Ec Addon. This allows you to extend the functionality of the EC e.g. by:

* post/preprocessing involving general storage operations
* general connectivity to external systems
* create new commands and restrictions in Vault
* event response (available in the Vault API)
* processing of specific jobs