[heywire]

>Back-testing is also incredibly valuable: We have repositories of every conversation or transaction we've ever exchanged with the banking networks, and when making changes to parsers or interpreters, we can compare their output against the old version on all of that historical data.

Are you referring to test data or actual live transaction data? The latter would seem like a huge liability and target for hackers.

[nelhage]

Live data, but they're stored redacted, and/or with sensitive data (e.g. credit card numbers) replaced with opaque tokens that reference an encrypted store that's carefully access-controlled.

[ersii]

Do you have any policy or decision made on how long you plan on storing that data? What I'm wondering, are the transactions currently "stored indefinitely"? (I'm referring to both data stores. The tokenized and the encrypted one)