The following list of commands is taken from the toybox roadmap[0] and
has been stripped down  accordingly.  Commands that belong to ubase[1]
are not listed here as well as commands that fall outside the scope of
sbase such as vi and sh are also not listed here.

at
awk
bc
diff
ed
file
find
getconf
join
logger
od
patch
pathchk
sed
stty
tabs
tput

The  following  programs have  been  imported  from  OpenBSD and  need
replacing or cleaning up:

csplit
col
expr
printf

If you are looking for some work  to do on sbase, another option is to
pick a utility of interest and check the POSIX specification to see if
there are any features missing.

[0] http://landley.net/toybox/roadmap.html
[1] http://git.suckless.org/ubase/