diff --git a/src/osmo_gsm_tester/event_loop.py b/src/osmo_gsm_tester/event_loop.py
new file mode 100644
index 0000000..d082898
--- /dev/null
+++ b/src/osmo_gsm_tester/event_loop.py
@@ -0,0 +1,64 @@
+# osmo_gsm_tester: Event loop
+#
+# Copyright (C) 2016-2017 by sysmocom - s.f.m.c. GmbH
+#
+# Author: Pau Espin Pedrol <pespin@sysmocom.de>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# These will be initialized before each test run.
+# A test script can thus establish its context by doing:
+# from osmo_gsm_tester.test import *
+import time
+poll_funcs = []
+
+def register_poll_func(func):
+    global poll_funcs
+    poll_funcs.append(func)
+
+def unregister_poll_func(func):
+    global poll_funcs
+    poll_funcs.remove(func)
+
+def poll():
+    global poll_funcs
+    for func in poll_funcs:
+        func()
+
+def wait_no_raise(log_obj, condition, condition_args, condition_kwargs, timeout, timestep):
+    if not timeout or timeout < 0:
+        log_obj.raise_exn('wait() *must* time out at some point. timeout=%r' % timeout)
+    if timestep < 0.1:
+        timestep = 0.1
+
+    started = time.time()
+    while True:
+        poll()
+        if condition(*condition_args, **condition_kwargs):
+            return True
+        waited = time.time() - started
+        if waited > timeout:
+            return False
+        time.sleep(timestep)
+
+def wait(log_obj, condition, *condition_args, timeout=300, timestep=1, **condition_kwargs):
+    if not wait_no_raise(log_obj, condition, condition_args, condition_kwargs, timeout, timestep):
+        log_obj.raise_exn('Wait timeout')
+
+def sleep(log_obj, seconds):
+    assert seconds > 0.
+    wait_no_raise(log_obj, lambda: False, [], {}, timeout=seconds, timestep=min(seconds, 1))
+
+
+# vim: expandtab tabstop=4 shiftwidth=4