I think Wave Apps (Free Financial Tracking) can link with Zapier.
Just be sure to double check with Zapier’s list of linkable apps.
Waveapps is something I’ve recently started using to do bookkeeping and Invoicing for multiple businesses and so far it looks like something that would work well with Beeminder via Zapier.
Something simple like datapoints linked to the balance of individual savings accounts and also to debt accounts should do the trick, they update on Waveapps, just like they do on Mint.com
Hope this is helpful. 
Good luck with your goals!!