There is no locale except C-Locale available in stdlib nano and we need time conversions.
stdlibnano doesn't provide a way to sustitute C-Locale (it's static)

How?

There is C-Locale builtin, therefore to convert time when it's possible it's used.
When it's not -> specifiers are substituted with our locale (i18 map)

 +--------+     +--------+
 |  Time  | <=> | Locale |
 +--------+     +--------+
    *
    |
 +-----------+
 |  SysTime  |
 +-----------+

Locale - ( utils::time::Locale) class for i18n Time internationalization management
Time - generall class for Time transformations
SysTime - class for most of possible usecases, initialized with system clock, can return time string in reference to past

For more see headers