This constant is set to the wezterm version string that is also reported by running wezterm -V. This can potentially be used to adjust configuration according to the installed version.

The version string looks like 20200406-151651-5b700e4. You can compare the strings lexicographically if you wish to test whether a given version is newer than another; the first component is the date on which the release was made, the second component is the time and the final component is a git hash.

local wezterm = require 'wezterm';
wezterm.log_error("Version " .. wezterm.version)