As per the design doc: UpsertConfig can also include customMergeStrategies if Groovy mergers is enabled.

{
   "upsertConfig":{
      "mode":"PARTIAL",
      "globalUpsertStategy": "OVERWRITE",
      "customMergeStrategies":{
         "field3":"Groovy({firstName+' '+lastName}, firstName, lastName)"
      },}
}

so these customMergeStrategies is executed before or after transformConfigs?

I think its after transform cc @User

It’s not implemented yet, but it will be after transform

ok, thanks