Running TS on replicated streaming postgres read only server

[bkd]

I have set up a relocation/master to have the indexing done on a replicated postgres node.

Setup is as follows:

Main server + code base + postgres main
Replication server+ code base + postgres replica

I will execute the ts:merge on the replication server NOT the main server

Naturally doing ts:merge is hitting the read-only database and trying to update the delta. It would be great to allow any rake that modifies the data to do this on the main server instead, then allow the indexing to be done without affecting performance - any suggestions to make this work?