Shen macros are interesting: here's an example of defining a macro to expand a func call to a call to the same func!
miniblog.
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C# has an interesting concept of second-class macros called Source Generators: https://devblogs.microsoft.com/dotnet/introducing-c-source-generators/
You can generate additional code at build time, but you can't transform existing expressions (unlike normal macros), so it's more amenable to tooling.
Linux historically used magic numbers to recognise structs being used incorrectly with void pointers. These have been increasingly replaced with type-safe macros: https://lwn.net/SubscriberLink/915163/ba83480903b82cb8/
Some of the original files were unchanged from the 90s!
Are there any noteworthy lisp dialects that don't have macros?
Macros aren't obligatory, but I'm struggling to think of any good lisp examples that lack them.