diff --git a/build.rb b/build.rb
index a727bd2..f4af12e 100755
--- a/build.rb
+++ b/build.rb
@@ -12,13 +12,27 @@
 #	so put a $ in front of the name which makes
 #	them global and not CONSTANT
 $CC="gcc"
-CFLAGS="-O1 -march=native -std=c11 -fmacro-prefix-map=src="
+CFLAGS="-O1 -march=native -std=c11"
 $EFLAGS = "" #extra flags
 APPNAME="chess"
 SRCDIR="src"
 BUILDDIR="build"
 INCLUDE=""
-LIB="-lraylib"
+LIB=""
+EXT=".c" #extension of source file
+#should maybe use environment variables for these
+
+#standalone funcs
+unless __FILE__ == $0
+	def error(msg)
+		puts "#{RUB}: error: #{msg}"
+		exit 1
+	end
+
+	def message(msg)
+		puts "#{RUB}: #{msg}"
+	end
+end
 
 #handle argument parsing yourself
 def parse(arg)
@@ -58,16 +72,18 @@ end
 
 #main build function
 def main
-	if Dir.children(SRCDIR).count == 0
-		error("src directory empty")
-	end
+	#if Dir.children(SRCDIR).count == 0
+		#error("src directory empty")
+	#end
+
+	error("src directory empty") unless Dir.children(SRCDIR)
 
 	threads = []
 
 	Dir.each_child(SRCDIR) {|x|
 		threads << Thread.new {
-			system("#{$CC} #{INCLUDE} #{CFLAGS} #{$EFLAGS} -c #{SRCDIR}/#{x} -o #{BUILDDIR}/#{File.basename(x, ".*") + ".o"}") if x.end_with?(".c")
-			message "compiled: #{x}\n" if x.end_with?(".c")
+			system("#{$CC} #{INCLUDE} #{CFLAGS} #{$EFLAGS} -c #{SRCDIR}/#{x} -o #{BUILDDIR}/#{File.basename(x, ".*") + ".o"}") if x.end_with?(EXT)
+			message "compiled: #{x}\n" if x.end_with?(EXT)
 		}
 	}