The verdict
If you bill through Stripe and want the straightforward route, pick Rewardful. It does a narrow job well and the vendor says set-up takes under 15 minutes.
If you run a shop, sell through several channels, want partners tied to deals in a CRM, or want an assistant to answer programme questions through an MCP server, pick Tapfiliate.
It depends on your stack, so I leave the winner open. Check the limits on each. Rewardful caps by affiliate revenue, while Tapfiliate caps clicks and conversions on the entry plan, with overage beyond that. Both move you up a tier if the programme works.