On OSX, when I run a build in ST3 that uses a shell_cmd, it appears to run the shell as a login shell, as opposed to an interactive or non-interactive shell. With my setup, that causes extraneous text to appear at the top of the output window. I’d rather run it as a non-interactive shell. Is there a way to configure how the shell is run?

That’s correct, login shells are used on OS X. This is required for $PATH to be set to something sensible. There currently aren’t any configuration options for this, although you can use ‘cmd’ rather than ‘shell_cmd’ as a workaround.

Using cmd instead is fine for build systems I write, but it doesn’t help built-in build systems. But I don’t see a ‘path’ setting inside Sublime either, so this might be the best you can do. Thanks.