Plaid Blog

While we were worried about event loop blockages causing outages, another more subtle problem would have been if event loop blockages doubled our user-facing latency. (If you read the section on latency ratios, you'll see that comparing parallel vs non-parallel workers was the most useful stat in figuring out how effectively we were using the event loop.) It definitely gave us peace-of-mind to know that event loop blockages wouldn't have an effect beyond the requests they're processing.

Honestly, the accounting for which would've been higher impact – investing in parallelism earlier, or adding infrastructure and having more resources to devote to other pressing needs – is difficult to do, even in retrospect. There was surprisingly little effort required to get to 4,000 node containers in an ECS cluster, other than deploy speed issues which we talked about in a previous post [1]. But it's possible this migration process would have been easier if we had done it sooner.

[1] https://blog.plaid.com/how-we-reduced-deployment-times-by-95/

web authentication is really not my area, but would you care to explain how this is safe ? For instance, I recognize when an app or a site is trying to use google to authenticate me, I am taken to google to authenticate. I'm not taken to the bank in this case. From https://blog.plaid.com/getting-started/, it looks like a curl request with plaintext password request made to plaid's servers.

Also from https://plaid.com/legal/longtail/, "You acknowledge that in accessing your data and information through the Service, your provider account access number(s), password(s), security question(s) and answer(s), account number(s), login information, and any other security or access information, and the actual data in your account(s) with such provider(s) such as bank and other account balances, credit card charges, debits and deposits (collectively, "Provider Account Data"), may be collected and stored in the Service."

Here are a couple great articles about code review that I've learned a lot from - they address the 'social' aspect of code review specifically, which I think is where you're having a hard time finding traction.

- https://blog.plaid.com/building-an-inclusive-code-review-culture/

- https://medium.freecodecamp.org/unlearning-toxic-behaviors-in-a-code-review-culture-b7c295452a3c

The takeaway is that it's a communication problem, and one of the first steps is probably setting some shared expectations. As others have mentioned, if you can't get alignment on expectations, you're not going to be happy in your job, but hopefully there's common ground somewhere, and you can all help each other level up technically and as a team.

I work at a company that is one of Plaid's largest customers and have chatted with their engineers before at a meetup in San Francisco. They were very open that they store the data themselves, and even shared this blog post with me about how they poll for data: https://blog.plaid.com/distributed-duplicate-detective/.

For what it's worth, I actually like Plaid's API compared to Yodlee, but have serious concerns about privacy. There's no way to determine if they are _just_ collecting transactions when you request the user's transactions as a dev. The user is handing over their user/pass/MFA and Plaid could be doing god knows what with that.