\version "2.21.1"

music = \relative c' {
  %\aikenHeads
  c\breve %\fermata
  c1 d2 e4 f8 f8_"rit" |
  % \override NoteHead.style = #'triangle
  % \override Flag.stencil = #modern-straight-flag
  g8 a4. a16 r16 r8 r4 |
  \bar "|."
}

testScore = {
  \new GrandStaff <<
    \new Staff \music
    \new Staff {
      \clef bass
      \transpose a a, \music
    }
  >>
}

\book {
  \bookOutputSuffix "Bravura"
  \score {
    \testScore
  }
  \paper {
   #(define fonts
     (set-global-fonts
      #:music "bravura"
      #:has-sizes? #f
    ))
  }
}
\book {
  \score {
    \testScore
  }
}