Now that sounds very cool.
Out of curiosity, do you have any plans to handle things that cannot be local first (for example with YNAB I like the Plaid Integration to pull transactions data out of banking).
Something like that for your application would need to clear through your own API right?
It's tough. I've wrestled with this for over a year. Bank syncing has to come from my server, which means by doing so you are giving us access to your transactions. No banking provider has any way for clients to contact them directly. I think this is possible with the right encryption, but nobody is working on it. I've given this feedback to Plaid but they don't care.
The majority of people need the convenience of syncing though. So I plan to launch it, and it'll go through my server, and I plan to communicate clearly the privacy that you are giving up by doing so.
I keep hoping to find a (maintained/viable) open source project that uses headless browsing to login locally and extract transaction details.
For my credit union, I "reverse engineered" the API and export multiple times throughout the day.
I wrote an extension that exports the data for CapitalOne, but I haven't gotten around to trying it either headless or even just in any automated fashion.
Easy automated export of user data, even beyond financials, is something I'd like to see more of. Feels like it could be a workaround while there's so little decentralization.
There _sort of_ is a solution where your computer directly connects to the bank. The format is called OFX (https://github.com/libofx/libofx), and there is a directory of banks that provide these files directly online. This site (https://www.ofxhome.com/) lists the URLs to use for each bank.
I used that for a while many years ago. But it's terrible and requires massive maintenance. For an app that requires connections to arbitrary banks, there's no way developers can support these direct downloads. There's always different errors in data for different banks, etc. Unfortunately, Plaid is solving a real problem