Tax calculations performed for VAT and/or sales taxes have been abstracted into so-called “tax modules”. An example of a custom tax module can be found in the directory utils/wa-tax-service in the source repository.
Before tax modules can be used, they need to be registered in the taxmodule table.
Important: Please note that there is a tight integration between the database ”pointing” to the tax module and the web server which expects to be able to load this Perl code to perform the prescribed calculations. If for some reason the application looses the ability to load the Perl module, this will break the ability to create or view invoices.