You’ve got a few issues here;
$USER is going to be the name of your actual user:
tmartin:dart:~> echo $USER
If you want to access your home directory, you need to use something like
/home/$USER or just
$HOME instead (which is generally better, a user’s home directory can be anywhere. See for example
tmartin:dart:~> echo $HOME
Additionally, anything in
working_dir in a build system that includes a
$ is treated as a variable and expands out, and anything that’s not a known variable is expanded out to be an empy string, so
$HOME expands out to an empty string and your path would end up being
/.config/sublime-text-3/packages as a result, which isn’t valid and so the working dir is not set (probably you see an error in the console when this build runs as a result).
To use something with a
$ in it you need to enter it as
\\$ instead; that gets loaded by the JSON parser as
\$, Sublime sees it and converts it to
$ without expanding anything, and it gets passed out to the command.
However all of that doesn’t really matter because it’s Sublime that needs to expand it if you’re going to use it in
working_dir and it doesn’t expand environment variables (that’s a job for your shell), so the directory won’t be set anyway.
The only variables you can use in
working_dir that Sublime will expand are listed in the documentation on build systems; there’s one that expands out to the packages directory already. So what you want is this: