add credits

Author: jethrodaniel

README.md

@@ -130,3 +130,12 @@ Bug reports and pull requests are welcome at https://github.com/jethrodaniel/mru
 ## License
 
 [MIT](https://spdx.org/licenses/MIT.html), same as [MRuby](https://github.com/mruby/mruby).
+
+## Credits
+
+This project is inspired by https://github.com/dantecatalfamo/mruby-zig (MIT):
+
+Some differences:
+
+- we use `@cImport` instead of zig bindings
+- we use `zig build` instead of `rake`