I work on a web/app-based personal finance tool, and just to clarify a few things regarding data aggregators (third parties that aggregate your financial data into personal finance apps like Plaid, MX, Finicity, etc).<p>There tends to be two main ways these aggregators interface with banks. The first is via screen-scraping or reverse-engineering internal APIs. The second is via direct integration (ie Oauth-type connections). Understandably, a lot of the HN-crew is skeptical of "handing over" their credentials to third parties, but for Oauth integrations, it's worth noting that:<p><pre><code> - you're redirected to the bank to enter your credentials (ie the third party never gets a chance to see them)
- often, you get to choose which permissions to allow (ie read vs write, read only, which accounts)
- the banks have signed off on the integration
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So even if you decide you're not comfortable with the screen-scrapes / internal APIs because you don't trust the aggregators, worth considering the direct ones.