Have you tried
\paper{ raggedright = ##t}
See
http://lilypond.org/doc/v2.2/Documentation/user/out-www/lilypond/Page-layout.html#Page%20layout
/Mats
Benjamin D. Smedberg wrote:
I do quite of bit of engraving in plainchant, both modern and
Gregorian. I have not discovered a layout mode which does not justify
the music on each line. In plainchant, the staff lines should extend
to the end of each line, but the actual notes and text should be
spaced and engraved as if it were left-justified (except for the