Yup. Smithy is from a lineage of internal tools that have been in use at Amazon since the early 2000s. From my dive into software archaeology at Amazon (I work there), there was a bit of SOAP in use in the 2000s, and some other internal model formats that are now obsolete claimed to be SOAP like. As the years went on, other internal formats came out to replace other formats, until the internal model format became something distantly inspired by SOAP, but very practical and tuned for cross language code generation so it could power AWS (that’s my take at least). That was in use for well over a decade before we built Smithy to improve on and open source the internal format.