Linebreaks and tabs in body.json are added for readability, the request body is without whitespace.

body.json

{
  "entity":"http://mxmerz.de",
  "types":["all"],
  "notification_path":"notifications/KysQKUWdOscs1AUkXmQr",
  "licenses":[]
}

post-followers.erl

%% HTTPS Request
"HTTP/1.1" "POST" "https://mxmerz.tent.is/tent/followers"

%% Headers
Connection: "keep-alive"
Host: "mxmerz.tent.is"
Port: 443
Link: "<http://tent.mxmerz.orion.uberspace.de/profile>; rel=\"https://tent.io/rels/profile\""
Accept-Encoding: "application/vnd.tent.v0+json"
Content-Type: "application/vnd.tent.v0+json"

%% Body
<<"{\"entity\":\"http://mxmerz.de\",\"types\":[\"all\"],\"notification_path\":\"notifications/KysQKUWdOscs1AUkXmQr\",\"licenses\":[]}">>