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 # cmath3d
 3d math library for C. Vectors, 3x3 matrices, quaternions. 32-bit floats.
 
+## motivation
 This library is intended for embedded projects where C++ is not used.
 In the author's opinion, C++'s feature set enables dramatically
 more readable 3d math code. However, many embedded projects stick with C
@@ -8,6 +9,7 @@ by necessity or preference. The goal of this project is to create the
 best possible programmer experience within the constraints of C syntax.
 **If cmath3d is missing something you need, feature requests are encouraged.**
 
+## design choices
 Unlike many other C libraries of this type, `cmath3d` passes arguments
 and returns results by value instead of by pointer and pointer-to-output.
 This choice has several motivations:
@@ -27,3 +29,7 @@ more stack memory than it should.
 I am currently researching ways to fix this problem, since I believe
 a SSA compiler with the ability to destructure structs should produce
 optimal code from this library.
+
+## note for users
+If you use `cmath3d` in your project,
+I would very much appreciate it if you leave a comment in #2.