At the beginning of August, I designed a query language for Preserves documents inspired by XPath. Here’s the draft specification. To give just a taste of the language, here are a couple of example selectors:

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.annotations ^ Documentation . 0 /

// [.^ [= Test + = NondeterministicTest]] [. 1 rec]

They’re properly explained in the Examples section of the spec.

So far, I’ve used Preserves Path to access portions of network packets received from the server in an implementation of the Syndicate network protocol for bash.