diff --git a/xqueue.lua b/xqueue.lua
index 3fa1ca1..c7d45a2 100644
--- a/xqueue.lua
+++ b/xqueue.lua
@@ -219,6 +219,57 @@ local function _table2tuple ( qformat )
 	return dostring(fun)
 end
 
+local function run_worker(space, xq, worker_num)
+	local worker = {
+		space   = space;
+		xq      = xq;
+		num     = worker_num;
+	}
+	worker.fname = space.name .. '.xq.wrk' .. tostring(worker_num)
+	if package.reload then
+		worker.generation = package.reload.count
+		worker.fname = worker.fname .. '.' .. package.reload.count
+	end
+	xq.workers.registered[worker.num] = worker
+	worker.fiber = fiber.create(function(space, xq, worker_num, worker)
+		fiber.name(string.sub(worker.fname,1,32))
+		repeat fiber.sleep(0.001) until space.xq
+		if worker.xq.ready then xq.ready:get() end
+		log.info("I am worker %s", worker_num)
+
+		while box.space[space.name] and space.xq == xq and xq.workers.registered[worker.num] do
+			if xq.workers.handler then
+				local task = space:take(1)
+				if task then
+					local key = xq:getkey(task)
+					local r,e = pcall(xq.workers.handler, task)
+
+					if not r then
+						log.error("Worker for {%s} has error: %s", key, e)
+					else
+						if xq.taken[ key ] then
+							space:ack(task)
+						end
+					end
+
+					if xq.taken[ key ] then
+						log.error("Worker for {%s} not released task", key)
+						space:release(task)
+					end
+				end
+			end
+			fiber.sleep(1)
+		end
+		log.info("worker %s ended", worker_num)
+	end, space, xq, worker_num, worker)
+
+	return setmetatable(worker, {
+		__serialize = function(self)
+			return ("[worker#%s] for %s"):format(self.num, self.space.name)
+		end;
+	})
+end
+
 local methods = {}
 
 function M.upgrade(space,opts,depth)
@@ -594,44 +645,20 @@ function M.upgrade(space,opts,depth)
 	end
 
 	if opts.worker then
-		local workers = opts.workers or 1
-		local worker = opts.worker
-		for i = 1,workers do
-			fiber.create(function(space,xq,i)
-				local fname = space.name .. '.xq.wrk' .. tostring(i)
-				if package.reload then fname = fname .. '.' .. package.reload.count end
-				fiber.name(string.sub(fname,1,32))
-				repeat fiber.sleep(0.001) until space.xq
-				if xq.ready then xq.ready:get() end
-				log.info("I am worker %s",i)
-				while box.space[space.name] and space.xq == xq do
-					local task = space:take(1)
-					if task then
-						local key = xq:getkey(task)
-						local r,e = pcall(worker,task)
-						if not r then
-							log.error("Worker for {%s} has error: %s", key, e)
-						else
-							if xq.taken[ key ] then
-								space:ack(task)
-							end
-						end
-						if xq.taken[ key ] then
-							log.error("Worker for {%s} not released task", key)
-							space:release(task)
-						end
-					end
-					fiber.sleep(1)
-				end
-				log.info("worker %s ended", i)
-			end,space,self,i)
+		self.workers = {
+			count      = opts.workers or 1;
+			handler    = opts.worker;
+			registered = {};
+		}
+		for i = 1, self.workers.count do
+			run_worker(space, self, i)
 		end
 	end
 
 	if have_runat then
 		self.runat_chan = fiber.channel(0)
 		self.runat = fiber.create(function(space,xq,runat_index)
-			local fname = space.name .. '.xq'
+			local fname = space.name .. '.xq.runat'
 			if package.reload then fname = fname .. '.' .. package.reload.count end
 			fiber.name(string.sub(fname,1,32))
 			repeat fiber.sleep(0.001) until space.xq
@@ -1315,6 +1342,57 @@ function methods:stats(pretty)
 	return stats
 end
 
+function methods:set_worker(handler)
+	local xq = self.xq
+	if not xq.workers then
+		xq.workers = {
+			count      = 1;
+			handler    = handler;
+			registered = {};
+		}
+	else
+		xq.workers.handler = handler
+	end
+
+	for i = 1, xq.workers.count do
+		if not xq.workers.registered[i] then
+			run_worker(self, xq, i)
+		end
+	end
+
+	return self
+end
+
+function methods:set_workers_cnt(cnt)
+	assert(type(cnt) == 'number', "worker count must be a number")
+
+	local xq = self.xq
+	local old_cnt = xq.workers and xq.workers.count or 0
+	if not xq.workers then
+		xq.workers = {
+			handler    = nil;
+			count      = cnt;
+			registered = {};
+		}
+	else
+		xq.workers.count = cnt
+	end
+
+	if old_cnt > xq.workers.count then
+		for i = xq.workers.count + 1, old_cnt do
+			xq.workers.registered[i] = nil
+		end
+	elseif old_cnt < xq.workers.count then
+		for i = old_cnt, xq.workers.count do
+			if i ~= 0 then
+				run_worker(self, xq, i)
+			end
+		end
+	end
+
+	return self
+end
+
 setmetatable(M,{
 	__call = function(M, space, opts)
 		M.upgrade(space,opts,1)