Postman which I thought worked locally on my computer, is down

If you're willing to use a CLI, you can try Hurl [1]. It's is an Open Source cli using libcurl to run and test HTTP requests with plain text. We use libcurl for the reliability, quickness and top features (HTTP/3 IPv6 for instance) and there are features like:

- requests chaining,

- capturing and passing data from a response to another request,

- response tests (JSONPath, XPath, SSL certs, redirects etc...)

There is nice syntax sugar for requesting REST/SOAP/GraphQL APIs but, at the core, it's just libcurl! You can export you files to curl commands for instance. (I'm one of the maintainers)

[1]: https://hurl.dev