server/nginx.conf

proxy_http_version 1.1;

# http://nginx.org/en/docs/http/websocket.html
map $http_upgrade $connection_upgrade {
    default upgrade;
    ''      close;
}

upstream lt-server {
    server 127.0.0.1:8000;
}

server {
	listen 80 default_server;
	listen [::]:80 default_server ipv6only=on;

	server_name .localtunnel.me;

	location / {
		proxy_pass http://lt-server/;

		proxy_set_header X-Real-IP $remote_addr;
		proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
		proxy_set_header Host $http_host;
		proxy_set_header X-Forwarded-Proto http;
		proxy_set_header X-NginX-Proxy true;
		proxy_set_header Upgrade $http_upgrade;
		proxy_set_header Connection $connection_upgrade;

		proxy_redirect off;
	}
}

server {
	listen 443 default_server ssl spdy;
	listen [::]:443 default_server ipv6only=on;

	server_name .localtuunel.me;

	ssl on;

	ssl_certificate      ...;
	ssl_certificate_key  ...;

	ssl_protocols              SSLv3 TLSv1 TLSv1.1 TLSv1.2;
	ssl_ciphers                RC4:HIGH:!aNULL:!MD5;
	ssl_prefer_server_ciphers  on;

	ssl_session_cache    shared:SSL:10m;
	ssl_session_timeout  10m;

	location / {
		proxy_pass http://lt-server/;

		proxy_set_header X-Real-IP $remote_addr;
		proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
		proxy_set_header Host $http_host;
		proxy_set_header X-Forwarded-Proto https;
		proxy_set_header Upgrade $http_upgrade;
		proxy_set_header X-NginX-Proxy true;
		proxy_set_header Connection $connection_upgrade;

		proxy_redirect off;
	}
}