[Font generation] cyrilic chars is not supported?

[T1mL3arn]

The font does support cyrilic. But ceramic font --font ./assets-src/Roboto-Medium.ttf --out ./assets/font --size 150 --charset "helloпривет !" gives this

info face="Roboto-Medium" size=150 bold=0 italic=0 unicode=1 stretchH=100 smooth=1 aa=1 padding=2,2,2,2 spacing=0,0 charset=""
common lineHeight=176 base=139 scaleW=208 scaleH=208 pages=1 packed=0 alphaChnl=0 redChnl=0 greenChnl=0 blueChnl=0
page id=0 file="Roboto-Medium.png"
chars count=6
char id=32 index=0 char=" " width=0 height=0 xoffset=0 yoffset=0 x=0 y=0 xadvance=37.2802734375 chnl=15 page=0
char id=33 index=1 char="!" width=22 height=110 xoffset=9.361328125 yoffset=42.5 x=96.5 y=2.5 xadvance=39.697265625 chnl=15 page=0
char id=101 index=2 char="e" width=71 height=84 xoffset=5.33251953124999 yoffset=68.5 x=2.5 y=120.5 xadvance=80.3466796875 chnl=15 page=0
char id=104 index=3 char="h" width=67 height=114 xoffset=8.24804687499999 yoffset=36.5 x=2.5 y=2.5 xadvance=83.349609375 chnl=15 page=0
char id=108 index=4 char="l" width=19 height=114 xoffset=9.6162109375 yoffset=36.5 x=73.5 y=2.5 xadvance=38.232421875 chnl=15 page=0
char id=111 index=5 char="o" width=75 height=84 xoffset=5.0537109375 yoffset=68.5 x=77.5 y=120.5 xadvance=85.107421875 chnl=15 page=0

Am I doing something wrong here?