I was setting up the wakatime-mode extension in a fresh Emacs For Mac OS X install so report to WakaTime. After setting up the CLI in my home directory I was getting the following message on saving:

It sounded like WakaTime Error (127) #35, but I was able to run the command at my shell.
Of course, the problem is that since I installed the extension into my home directory, I specified it this way in the init.el
:
(setq wakatime-cli-path "~/.wakatime/wakatime-cli")
Unfortunately, ~
won’t get expanded like it will in my zsh
.
Changing it to the full path, i.e.,
(setq wakatime-cli-path "/Users/powell/.wakatime/wakatime-cli")
will resolve the error in WakaTime.