gluon/scripts/site_config.lua

local config = os.getenv('GLUON_SITE_CONFIG')

local function loader()
   coroutine.yield('return ')
   coroutine.yield(io.open(config):read('*a'))
end

-- setfenv doesn't work with Lua 5.2 anymore, but we're using 5.1
return setfenv(assert(load(coroutine.wrap(loader), 'site.conf')), {})()