Chase offers a sample NACHA file to look at. Notice the rows padded with 9s. It’s an artifact of a 1970s rule about magnetic tape, "always fill the block". To this day, total line count *must* be a multiple of ten; otherwise the bank will drop the transaction.

Of course, larger Fintech firms (think Stripe) wrap it up with modern APIs, but SFTP is the default for most US Banks. Hilariously, NACHA rules don’t clarify *how* transactions should be encrypted. Only that “commercially reasonable” cryptography should be used.

Legally, not much is stopping you from writing your own txt file, putting it on a gameboy, and transferring $1 Million to a Federal Bank. As long as its: 1. Electronic 2. “reasonably” encrypted It meets minimum NACHA operating rules. The medium doesn’t matter, as long as

@lauriewired Could we... get like a non technical tweet from you every once and a while? Just so we know you're still human.

@DogeStoned35151

@lauriewired SFTP is built on top of FTP which was built atop RFC 959 built in part atop "TAC" atop RFC 931 atop old railways atop ancient Roman roads designed for two horses but we'll keep supporting all of it because it kinda sorta works well enough and who knows the horses might come back.

@lauriewired cost 0.2 cent but change you >$10 for the connivence

@lauriewired Other than the quirky magnetic tape 9 track format, this is about what any data protocol would carry. A modern protocol would also be in plain text, also encrypted. The big question is whether anyone can submit this, or do the banks have authentication as well to ensure only

@lauriewired s/quirky/batshit/

@lauriewired I found this out the first week of working at a fintech company. We literally just upload NACHA files to Chase via SFTP like it’s a freaking mailbox 😭

@lauriewired same thing with the 2003 Congressional Check 21 Act allows you to send encrypted digital checks! I built a Open Source solution for this 👇 https://checkard.com

@lauriewired @grok explain how blockchains are better than this

@lauriewired Blew my SOC2 off!

@lauriewired @spandrell4 The original Internet protocols were well designed. Just needed to slap an s on them. In fact, I’m wishing some of them would make a comeback, like nntp.

@lauriewired my biggest takeaway from this is laurie's name is rahul

@lauriewired Your money moves on text rails..

@lauriewired @grok please explain this to me in detail

@lauriewired I used to have to manually build nacha files for banks, shit was not fun lol

@lauriewired #updatethesystem still my favourite @coinbase meme

@lauriewired wow

@lauriewired This is the kind of autistic shit I’m here for 👍

@lauriewired Surprisingly, a lot of other important stuff happens over FTP in the financial system:

@lauriewired Not to be the guy to "defend" ACH, but a major part of it is that the ACH process includes settlement of funds at scale for the financial institutions. The amount of transactions processed vs the cost + integrated settlement actually presents an attractive design when you factor

@lauriewired People react like this is bad. Simplicity is good!

@lauriewired SFTP + Fixed Width rules the world in ways that JSON could never.

@lauriewired so much stuff still works like this it's insane, the ole EDI systems from everything to insurance, payments, purchasing, health, logistics, etc etc..

@lauriewired Filezilla. wow, that's a program I have not seen....in a long time.

@lauriewired That’s wrong. Nacha is a structured file format. The transmission protocol does not need to be sftp. the requirement is just encryption. You are also wrong about calling it a tunnel since tunneling implies encapsulation of l3 headers as opposed to a transport protocol that just

@lauriewired This is so wild! People say bitcoin is nothing. If only they knew that their paycheck that appears in their bank account is probably an SFTP transfer indicating that one bank has agreed with another bank that the transfer is legit. There’s no there there except that we believe

@lauriewired You should see how the DTCC tracks trades lol

@lauriewired Yeah, so this is the same for pharmacy reporting and lots of transactions. ETLs and things are often submitted via text over an encrypted connection. They used to not even be encrypted. I've written and created the foundational technology for this stuff for a long time.

@lauriewired And wait until you learn that SWIFT MT messages are ASCII files with breakers because it just mimics TLFX and only now is replaced by …. XML (yeah). And basically all banks do their own flavor anyway as there si many hacks in backoffice billing bank systems it is impossible to

@lauriewired This sounds like an evolution of the old "EDI" standards

@lauriewired dear god