--- a/plugins/mod_csi_simple.lua	Sun Mar 24 20:12:22 2019 +0100
+++ b/plugins/mod_csi_simple.lua	Sun Mar 24 20:22:01 2019 +0100
@@ -9,42 +9,8 @@
 local jid = require "util.jid";
 local st = require "util.stanza";
 local dt = require "util.datetime";
-local new_queue = require "util.queue".new;
 local filters = require "util.filters";
 
-local function new_pump(output, ...)
-	-- luacheck: ignore 212/self
-	local q = new_queue(...);
-	local flush = true;
-	function q:pause()
-		flush = false;
-	end
-	function q:resume()
-		flush = true;
-		return q:flush();
-	end
-	local push = q.push;
-	function q:push(item)
-		local ok = push(self, item);
-		if not ok then
-			q:flush();
-			output(item, self);
-		elseif flush then
-			return q:flush();
-		end
-		return true;
-	end
-	function q:flush()
-		local item = self:pop();
-		while item do
-			output(item, self);
-			item = self:pop();
-		end
-		return true;
-	end
-	return q;
-end
-
 local queue_size = module:get_option_number("csi_queue_size", 256);
 
 module:hook("csi-is-stanza-important", function (event)
@@ -109,45 +75,20 @@
 	return data;
 end
 
-local function flush_pump(data, session)
-	session.pump:flush();
-	return data;
-end
-
 module:hook("csi-client-inactive", function (event)
 	local session = event.origin;
 	if session.conn and session.conn and session.conn.pause_writes then
-		session.log("info", "Native net.server buffer management mode");
 		session.conn:pause_writes();
 		filters.add_filter(session, "stanzas/out", manage_buffer);
 		filters.add_filter(session, "bytes/in", flush_buffer);
-	elseif session.pump then
-		session.pump:pause();
 	else
-		local bare_jid = jid.join(session.username, session.host);
-		local send = session.send;
-		session._orig_send = send;
-		local pump = new_pump(session.send, queue_size);
-		pump:pause();
-		session.pump = pump;
-		filters.add_filter(session, "bytes/in", flush_pump);
-		function session.send(stanza)
-			if session.state == "active" or module:fire_event("csi-is-stanza-important", { stanza = stanza, session = session }) then
-				pump:flush();
-				send(stanza);
-			else
-				pump:push(with_timestamp(stanza, bare_jid));
-			end
-			return true;
-		end
+		session.log("warn", "Session connection does not support write pausing");
 	end
 end);
 
 module:hook("csi-client-active", function (event)
 	local session = event.origin;
-	if session.pump then
-		session.pump:resume();
-	elseif session.conn and session.conn and session.conn.resume_writes then
+	if session.conn and session.conn and session.conn.resume_writes then
 		filters.remove_filter(session, "stanzas/out", manage_buffer);
 		filters.remove_filter(session, "bytes/in", flush_buffer);
 		session.conn:resume_writes();