Here are the environment variables (see see Environment Variables in Guile Reference) that affect the run-time behavior of mes:
MES_BOOT to change the initial Scheme program that mes runs.
The initial size of the arena see 5.3 in SICP in cells. Default: 20,000.
The maximum size of the arena in cells. Default: 100,000,000.
The maximum size of a string. Default: 524,288.
This variable may be used to augment the path that is searched for
Scheme files when loading. Its value should be a colon-separated list
of directories. If it contains the special path component
(ellipsis), then the default path is put in place of the ellipsis,
otherwise the default path is placed at the end. The result is stored
Mes uses GUILE_LOAD_PATH for compatibility with Guile.