diff --git a/Makefile b/Makefile
index 8950657..9dea34f 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,7 @@
+# Linux / macOS users: This Makefile is mainly intended for BSD
+#                      systems. You probably want to look at or
+#                      edit the GNUmakefile.
+# -------------------------------------------------------------
 VERSION ?= 2021.10
 KEYPAIR ?= 2021-10
 PREFIX ?= /usr/local
diff --git a/multicore.retro b/multicore.retro
index 3414499..57c08b2 100644
--- a/multicore.retro
+++ b/multicore.retro
@@ -1,4 +1,4 @@
-Testing for multiple core support.
+# Multicore Support
 
 ~~~
 :core #8000 io:scan-for io:invoke ;
@@ -12,7 +12,7 @@ Testing for multiple core support.
 :core:wr    (vn-) #6 core ;
 ~~~
 
-~~~
+```
 'Done var
 
 :a [ @Done #100000 gt? [ core:pause-current ] if &Done v:inc $a c:put ] forever ;
@@ -26,4 +26,4 @@ Testing for multiple core support.
 #4 core:init  &d #4 core:start
 
 core:pause-current
-~~~
+```