EDI is the part of API history that humbles me, and it should humble the industry. Electronic Data Interchange is the exchange of structured business documents between trading partners in a standardized format — purchase orders, invoices, shipping notices — and it has been running global commerce since long before anyone said “API.”
It is, quite literally, the original API: a technical basis for automated commercial conversation between two organizations, complete with message formats, transmission, and the software to handle it. Trillions of dollars still move through it every year.
Three lessons worth carrying. First, the hard part of B2B integration was never the transport; it was agreeing on the meaning of the documents, and EDI’s standards work on that took decades. Modern APIs have mostly skipped that agreement and are paying for it in bespoke integration. Second, longevity comes from standards plus contractual relationships, not from developer enthusiasm — EDI has outlasted every hype cycle since the 1970s. Third, the sheer volume still flowing through EDI tells you the API economy is much earlier in its life than the conference circuit suggests.
And a caution: APIs are often a façade over a legacy view of the world. Putting JSON in front of an EDI process without rethinking the model gives you a modern-looking interface to a 1985 design.
