Limbo

Limbo is a programming language developed by Bell Labs, known for its simplicity and safety features. It is primarily used for writing system software, especially in distributed and concurrent computing environments.

Hello, world code example:

implement Command;
 
 include "sys.m";
     sys: Sys;
 
 include "draw.m";
 
 include "sh.m";
 
 init(nil: ref Draw->Context, nil: list of string)
 {
     sys = load Sys Sys->PATH;
     sys->print("Hello world!\n");
 }

Popularity: Less than 1% of developers are using or have used this language.*
*According to StackOverflow's 2023 survey.

Repositories on GitHub: 589

• Official Website
• Wikipedia page