Leafpub is developed and tested on Apache, but there's nothing stopping you from using another web server. NGINX is a popular alternative 

Here's a sample config that will get you up and running in no time, courtesy of @calmdev:

server {
  listen                *:80;
  server_name           example.com;
  access_log            /path/to/example.com.access.log;
  error_log             /path/to/example.com.error.log;

  location / {
    root  /path/to/example.com/app;
    try_files  $uri  $uri/  /index.php?$args;
    index index.php;
  }

  location ~ /(backups) {
    deny all;
  }

  location ~ \.php$ {
    root  /path/to/example.com/app;
    try_files  $uri  $uri/  /index.php?$args;
    index  index.html index.htm index.php;

    fastcgi_param PATH_INFO $fastcgi_path_info;
    fastcgi_param PATH_TRANSLATED $document_root$fastcgi_path_info;
    fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;

    fastcgi_pass 127.0.0.1:9000;
    fastcgi_index index.php;
    fastcgi_split_path_info ^(.+\.php)(/.+)$;
    fastcgi_intercept_errors on;
    include fastcgi_params;
  }
}

Once you've setup NGINX, copy over your existing Leafpub site or run the installer as usual.

Need help getting things setup? Try asking on the community forum!