Is there a programming solution to the Third Party Payment Aggregator (TPPA) problem?

Our web app has hit the TPPA problem. We want to allow our users to use their own merchant account and gateway to collect payment from our user's customer. This helps us limit our chargeback liability and headaches with handling all of our user's customer's transactions.

I have seen integrations like this in web apps like formstack's payment integration and came across Braintree's multi merchant account processing which seems promising. There are old discussions on hackernews (can't link due to StackOverflow's spam prevention for new accounts) about the third party pa开发者_开发百科yment aggregation problem, but nothing besides Braintree was suggested as a solution.

Currently, are there any other solutions or competitors to Braintree?

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Full disclosure: I'm a developer for PayJunction, though I don't work directly on the payment processing system. That said, since my employer is in this space, I forwarded your question on to someone who would know. Here's what he sent me back (that third link does have some sample code I worked on):

PayJunction is a multi merchant capable gateway as well, and they have a rich user interface on top of their API. Unique credentials are issued for each merchant account and you simply send the credentials via the API for the account you want to charge. Your clients would setup their own accounts and you would have no chargeback liability.

See video's here: http://www.payjunction.com/trinity/merchant-account/videos.action

API details here: http://support.payjunction.com/trinity/support/view.action?knowledgeBase.knbKnowledgeBaseId=585

Code Samples here: http://support.payjunction.com/trinity/support/main.action?search.knowledgeBaseCategory.kbcParentId=43