fastness ➞ git commit -a                                                                         ~/code/rbx_cpp
Created commit a9ef4b5: Correct shift_tuple and string_append instructions
 1 files changed, 8 insertions(+), 5 deletions(-)
fastness ➞ git pull                                                                              ~/code/rbx_cpp
Already up-to-date.
fastness ➞ git push                                                                              ~/code/rbx_cpp
Counting objects: 7, done.
Compressing objects: 100% (4/4), done.
Writing objects: 100% (4/4), 455 bytes, done.
Total 4 (delta 3), reused 0 (delta 0)
To git@git.rubini.us:code
   2342cd8..a9ef4b5  cpp -> cpp
 ! [rejected]        master -> master (non-fast forward)
Updating github..
error: failed to push some refs to 'git@git.rubini.us:code'