diff --git a/fonttest.tex b/fonttest.tex
new file mode 100644
index 0000000..9a897ad
--- /dev/null
+++ b/fonttest.tex
@@ -0,0 +1,60 @@
+\documentclass[a4paper,12pt]{scrartcl}
+\usepackage{luacode}
+\usepackage{fontspec}
+\usepackage{xcolor}
+\begin{document}
+\setmainfont{Recursive}[
+	Renderer=HarfBuzz,
+	ItalicFont=Recursive,
+	BoldFont=Recursive,
+	BoldItalicFont=Recursive,
+	UprightFeatures={
+		RawFeature={+ss01,+ss02,+ss08,+case},
+	},
+	BoldFeatures={RawFeature={+axis={wght=700}}},
+	BoldItalicFeatures={RawFeature={+axis={wght=700,slnt=-15,CRSV=1}}},
+	ItalicFeatures={RawFeature={+axis={slnt=-15,CRSV=1}}}
+]
+\begin{luacode*}
+local vft =
+	[[\addfontfeatures{RawFeature={+axis={MONO=%.2f,CASL=%.2f,slnt=%.2f,CRSV=%d,wght=%.0f}}}]]
+function vf( MONO, CASL, slnt, CRSV, wght )
+	local s = vft:format( MONO, CASL, slnt, CRSV, wght )
+	return s
+end
+local N, buf = 3, { }
+function c( v )
+	if type( v ) == "number" then  return { v, v }  end
+	if not v[2] then  v[2] = v[1]  end
+	return v
+end
+function lerp( MONO, CASL, slnt, CRSV, wght, C,M,Y,J,F )
+	F = F or 1
+	local B = { c(MONO), c(CASL), c(slnt), c(CRSV), c(wght) }
+	local color = { C,M,Y }
+	local params = { }
+	for k = 0, N do
+		local t = k/N
+		color[J] = (F<0) and (1+(F*t)) or (F*t)
+		for i = 1, #B do
+			params[i] = B[i][1] + (B[i][2] - B[i][1])*t
+		end
+		local s = vf( table.unpack( params ) )
+		--[[ texio.write_nl( s ) ]]
+		buf[#buf+1] = s
+		local C = ("%.2f,%.2f,%.2f,0.65"):format( table.unpack( color ) )
+		buf[#buf+1] = "\\textcolor[cmyk]{"..C.."}{Test?} "
+	end
+	buf[#buf+1] = "\\par "
+end
+lerp( 0, {0,1},       0, 0,       300,   0,0,0,2    )
+lerp( 0,     1, {-15,0}, 0,       300,   0,1,0,3    )
+lerp( 0, {1,0},     -15, 0,       300,   0,1,1,2,-1 )
+lerp( 0,     0,     -15, 0, {800,300},   0,0,1,1    )
+lerp( 0, {0,1},     -15, 0,       800,   1,0,1,2    )
+lerp( 0,     1, {0,-15}, 0,       800,   1,1,1,3,-1 )
+lerp( 0, {1,0},       0, 0,       800,   1,1,0,2,-1 )
+lerp( 0,     0,       0, 0, {300,800},   1,0,0,1,-1 )
+tex.print( table.concat( buf, "" ) )
+\end{luacode*}
+\end{document}