diff --git a/README.rst b/README.rst
index bf36af545..6dcb4c46b 100644
--- a/README.rst
+++ b/README.rst
@@ -31,7 +31,7 @@ projects.
 Join us
 -------
 
-- http://launchpad.net/taskflow
+- https://launchpad.net/taskflow
 
 Testing and requirements
 ------------------------
@@ -70,8 +70,8 @@ We also have sphinx documentation in ``docs/source``.
 
     $ python setup.py build_sphinx
 
-.. _kazoo: https://kazoo.readthedocs.org/
+.. _kazoo: https://kazoo.readthedocs.io/en/latest/
 .. _sqlalchemy: https://www.sqlalchemy.org/
-.. _kombu: https://kombu.readthedocs.org/
+.. _kombu: https://kombu.readthedocs.io/en/latest/
 .. _eventlet: http://eventlet.net/
 .. _tox: https://tox.testrun.org/
diff --git a/doc/source/user/jobs.rst b/doc/source/user/jobs.rst
index 6a4dc2d2d..31a1f0183 100644
--- a/doc/source/user/jobs.rst
+++ b/doc/source/user/jobs.rst
@@ -334,8 +334,8 @@ the claim by then, therefore both would be *working* on a job.
    (combine this with the prior suggestions and *most* dual-engine issues
    should be avoided).
 
-.. _idempotent: http://en.wikipedia.org/wiki/Idempotence
-.. _preemptable: http://en.wikipedia.org/wiki/Preemption_%28computing%29
+.. _idempotent: https://en.wikipedia.org/wiki/Idempotence
+.. _preemptable: https://en.wikipedia.org/wiki/Preemption_%28computing%29
 
 Interfaces
 ==========
@@ -367,6 +367,6 @@ Hierarchy
 
 .. _paradigm shift: https://wiki.openstack.org/wiki/TaskFlow/Paradigm_shifts#Workflow_ownership_transfer
 .. _zookeeper: http://zookeeper.apache.org/
-.. _kazoo: http://kazoo.readthedocs.org/
+.. _kazoo: https://kazoo.readthedocs.io/en/latest/
 .. _stevedore: https://docs.openstack.org/stevedore/latest
-.. _redis: http://redis.io/
+.. _redis: https://redis.io/
diff --git a/doc/source/user/persistence.rst b/doc/source/user/persistence.rst
index 0f8dc93b5..c28c7fe00 100644
--- a/doc/source/user/persistence.rst
+++ b/doc/source/user/persistence.rst
@@ -235,7 +235,7 @@ version      TEXT      False
 parent_uuid  VARCHAR   False
 ===========  ========  =============
 
-.. _sqlalchemy: http://www.sqlalchemy.org/docs/
+.. _sqlalchemy: https://docs.sqlalchemy.org/en/latest/
 .. _ACID: https://en.wikipedia.org/wiki/ACID
 
 .. note::
@@ -254,8 +254,8 @@ parent_uuid  VARCHAR   False
     ``traditional`` when selecting your mysql + sqlalchemy based
     backend (see the `mysql modes`_ documentation for what this implies).
 
-.. _1416088: http://bugs.launchpad.net/taskflow/+bug/1416088
-.. _mysql modes: http://dev.mysql.com/doc/refman/5.0/en/sql-mode.html
+.. _1416088: https://bugs.launchpad.net/taskflow/+bug/1416088
+.. _mysql modes: https://dev.mysql.com/doc/refman/8.0/en/sql-mode.html
 
 Zookeeper
 ---------
@@ -276,7 +276,7 @@ as the database connection types listed previously).
     for implementation details.
 
 .. _zookeeper: http://zookeeper.apache.org
-.. _kazoo: http://kazoo.readthedocs.org/
+.. _kazoo: https://kazoo.readthedocs.io/en/latest/
 
 Interfaces
 ==========
diff --git a/taskflow/jobs/backends/impl_redis.py b/taskflow/jobs/backends/impl_redis.py
index fca2699cb..7a006e28b 100644
--- a/taskflow/jobs/backends/impl_redis.py
+++ b/taskflow/jobs/backends/impl_redis.py
@@ -253,9 +253,9 @@ class RedisJobBoard(base.JobBoard):
     claim is kept alive while it is being worked on by using
     the :py:meth:`~.RedisJob.extend_expiry` method periodically.
 
-    .. _msgpack: http://msgpack.org/
-    .. _redis: http://redis.io/
-    .. _hash: http://redis.io/topics/data-types#hashes
+    .. _msgpack: https://msgpack.org/
+    .. _redis: https://redis.io/
+    .. _hash: https://redis.io/topics/data-types#hashes
     """
 
     CLIENT_CONF_TRANSFERS = tuple([
diff --git a/taskflow/jobs/backends/impl_zookeeper.py b/taskflow/jobs/backends/impl_zookeeper.py
index dd2392e95..6ee222274 100644
--- a/taskflow/jobs/backends/impl_zookeeper.py
+++ b/taskflow/jobs/backends/impl_zookeeper.py
@@ -211,7 +211,7 @@ class ZookeeperJob(base.Job):
 class ZookeeperJobBoard(base.NotifyingJobBoard):
     """A jobboard backed by `zookeeper`_.
 
-    Powered by the `kazoo <http://kazoo.readthedocs.org/>`_ library.
+    Powered by the `kazoo <https://kazoo.readthedocs.io/en/latest/>`_ library.
 
     This jobboard creates *sequenced* persistent znodes in a directory in
     zookeeper and uses zookeeper watches to notify other jobboards of
@@ -244,7 +244,7 @@ class ZookeeperJobBoard(base.NotifyingJobBoard):
     specification
 
     .. _zookeeper: http://zookeeper.apache.org/
-    .. _json: http://json.org/
+    .. _json: https://json.org/
     """
 
     #: Transaction support was added in 3.4.0 so we need at least that version.
diff --git a/taskflow/utils/kazoo_utils.py b/taskflow/utils/kazoo_utils.py
index 4485b5abd..20146b404 100644
--- a/taskflow/utils/kazoo_utils.py
+++ b/taskflow/utils/kazoo_utils.py
@@ -172,22 +172,22 @@ def make_client(conf):
       client with alternate async strategies (the default is `thread`_
       based, but `gevent`_, or `eventlet`_ ones can be provided as needed)
 
-    .. _client: http://kazoo.readthedocs.org/en/latest/api/client.html
-    .. _kazoo: http://kazoo.readthedocs.org/
-    .. _retry: http://kazoo.readthedocs.org/en/latest/api/retry.html
-    .. _gevent: http://kazoo.readthedocs.org/en/latest/api/\
+    .. _client: https://kazoo.readthedocs.io/en/latest/api/client.html
+    .. _kazoo: https://kazoo.readthedocs.io/
+    .. _retry: https://kazoo.readthedocs.io/en/latest/api/retry.html
+    .. _gevent: https://kazoo.readthedocs.io/en/latest/api/\
                 handlers/gevent.html
-    .. _eventlet: http://kazoo.readthedocs.org/en/latest/api/\
+    .. _eventlet: https://kazoo.readthedocs.io/en/latest/api/\
                   handlers/eventlet.html
-    .. _thread: http://kazoo.readthedocs.org/en/latest/api/\
+    .. _thread: https://kazoo.readthedocs.io/en/latest/api/\
                 handlers/threading.html
     """
-    # See: http://kazoo.readthedocs.org/en/latest/api/client.html
+    # See: https://kazoo.readthedocs.io/en/latest/api/client.html
     client_kwargs = {
         'read_only': bool(conf.get('read_only')),
         'randomize_hosts': bool(conf.get('randomize_hosts')),
     }
-    # See: http://kazoo.readthedocs.org/en/latest/api/retry.html
+    # See: https://kazoo.readthedocs.io/en/latest/api/retry.html
     if 'command_retry' in conf:
         client_kwargs['command_retry'] = conf['command_retry']
     if 'connection_retry' in conf: