"fix" issue #3 by manually including the cyrillic small e, u0435

build.sh

@@ -44,7 +44,10 @@ for font in \
     subset_ttf="${font%.ttf}-Subset.ttf"
     hb-subset "$font" \
         --output-file="$subset_ttf" \
-        --keep-everything \
+        --text-file=all_chars.txt \
+        --layout-features='*' \
+        --passthrough-tables \
+        --unicodes+="0x0435" # this is the cyrillic e. For some reason, alegreya's ff calt breaks without it
 
     woff2_compress "$subset_ttf"