diff --git a/doc/build.md b/doc/build.md
index 53fb3d5f4..a127c1678 100644
--- a/doc/build.md
+++ b/doc/build.md
@@ -7,7 +7,7 @@ Grin's programming language `rust` has build targets for most platforms.
 
 What's working so far?
 
-* Linux x86\_64 and MacOS [grin + mining + development]
+* Linux x86\_64 and macOS [grin + mining + development]
 * Not Windows 10 yet [grin kind-of builds. No mining yet. Help wanted!]
 
 ## Requirements