diff --git a/backfiller/backfiller/main.py b/backfiller/backfiller/main.py
index e42251d..0dcafef 100644
--- a/backfiller/backfiller/main.py
+++ b/backfiller/backfiller/main.py
@@ -330,11 +330,12 @@ class BackfillerWorker(object):
 		del self.manager.workers[self.node]
 
 							
-def main(base_dir='.', stream='', variants='', metrics_port=8002,
+def main(base_dir='.', streams='', variants='', metrics_port=8002,
 	static_nodes='', backdoor_port=0, start=None, run_once=False,
 	node_source=None):
 	"""Backfiller service."""
 
+	streams = streams.split(',') if variants else []
 	variants = variants.split(',') if variants else []
 	static_nodes = static_nodes.split(',') if static_nodes else []
 
@@ -344,16 +345,40 @@ def main(base_dir='.', stream='', variants='', metrics_port=8002,
 		except ValueError:
 			start = dateutil.parser.parse(start)
 
-	manager = BackfillerManager(base_dir, stream, variants, static_nodes, start, run_once, node_source)
-	gevent.signal(signal.SIGTERM, manager.stop)
-
 	common.PromLogCountsHandler.install()
 	common.install_stacksampler()
 	prom.start_http_server(metrics_port)
 
+	managers = []
+	workers = []
+	for stream in streams:
+		logging.info('Starting backfilling {} with {} as variants to {}'.format(stream, ', '.join(variants), base_dir))
+		manager = BackfillerManager(base_dir, stream, variants, static_nodes, start, run_once, node_source)
+		managers.append(manager)
+		workers.append(gevent.spawn(manager.run))
+
+	def stop():
+		for manager in managers:
+			manager.stop()
+
+	gevent.signal(signal.SIGTERM, stop)
+
 	if backdoor_port:
 		gevent.backdoor.BackdoorServer(('127.0.0.1', backdoor_port), locals=locals()).start()
 
-	logging.info('Starting backfilling {} with {} as variants to {}'.format(stream, ', '.join(variants), base_dir))
-	manager.run()
+	# Wait for any to die
+	gevent.wait(workers, count=1)
+	# If one has stopped, either:
+	# 1. stop() was called and all are stopping
+	# 2. one errored and we should stop all remaining and report the error
+	# Our behaviour in both cases is the same:
+	# 1. Tell all managers to gracefully stop
+	stop()
+	# 2. Wait (with timeout) until they've stopped
+	gevent.wait(workers)
+	# 3. Check if any of them failed. If they did, report it. If mulitple
+	#    failed, we report one arbitrarily.
+	for worker in workers:
+		worker.get()
+
 	logging.info('Gracefully stopped')