diff --git a/vcsserver/lib/_vendor/jsonlogger/__init__.py b/vcsserver/lib/_vendor/jsonlogger/__init__.py
--- a/vcsserver/lib/_vendor/jsonlogger/__init__.py
+++ b/vcsserver/lib/_vendor/jsonlogger/__init__.py
@@ -3,7 +3,6 @@ This library is provided to allow standa
 to output log data as JSON formatted strings
 '''
 import logging
-import json
 import re
 from datetime import date, datetime, time, tzinfo, timedelta
 import traceback
@@ -13,13 +12,8 @@ from inspect import istraceback
 
 from collections import OrderedDict
 
-
-def _inject_req_id(record, *args, **kwargs):
-    return record
-
-
-ExceptionAwareFormatter = logging.Formatter
-
+from ...logging_formatter import _inject_req_id, ExceptionAwareFormatter
+from ...ext_json import sjson as json
 
 ZERO = timedelta(0)
 HOUR = timedelta(hours=1)
diff --git a/vcsserver/lib/_vendor/redis_lock/__init__.py b/vcsserver/lib/_vendor/redis_lock/__init__.py
--- a/vcsserver/lib/_vendor/redis_lock/__init__.py
+++ b/vcsserver/lib/_vendor/redis_lock/__init__.py
@@ -111,11 +111,12 @@ class Lock:
     extend_script = None
     reset_script = None
     reset_all_script = None
+    blocking = None
 
     _lock_renewal_interval: float
     _lock_renewal_thread: Union[threading.Thread, None]
 
-    def __init__(self, redis_client, name, expire=None, id=None, auto_renewal=False, strict=True, signal_expire=1000):
+    def __init__(self, redis_client, name, expire=None, id=None, auto_renewal=False, strict=True, signal_expire=1000, blocking=True):
         """
         :param redis_client:
             An instance of :class:`~StrictRedis`.
@@ -143,6 +144,9 @@ class Lock:
             If set ``True`` then the ``redis_client`` needs to be an instance of ``redis.StrictRedis``.
         :param signal_expire:
             Advanced option to override signal list expiration in milliseconds. Increase it for very slow clients. Default: ``1000``.
+        :param blocking:
+            Boolean value specifying whether lock should be blocking or not.
+            Used in `__enter__` method.
         """
         if strict and not isinstance(redis_client, StrictRedis):
             raise ValueError("redis_client must be instance of StrictRedis. "
@@ -179,6 +183,8 @@ class Lock:
                                        else None)
         self._lock_renewal_thread = None
 
+        self.blocking = blocking
+
         self.register_scripts(redis_client)
 
     @classmethod
@@ -342,9 +348,11 @@ class Lock:
         loggers["refresh.exit"].debug("Renewal thread for Lock(%r) exited.", self._name)
 
     def __enter__(self):
-        acquired = self.acquire(blocking=True)
+        acquired = self.acquire(blocking=self.blocking)
         if not acquired:
-            raise AssertionError(f"Lock({self._name}) wasn't acquired, but blocking=True was used!")
+            if self.blocking:
+                raise AssertionError(f"Lock({self._name}) wasn't acquired, but blocking=True was used!")
+            raise NotAcquired(f"Lock({self._name}) is not acquired or it already expired.")
         return self
 
     def __exit__(self, exc_type=None, exc_value=None, traceback=None):
diff --git a/vcsserver/lib/_vendor/statsd/__init__.py b/vcsserver/lib/_vendor/statsd/__init__.py
--- a/vcsserver/lib/_vendor/statsd/__init__.py
+++ b/vcsserver/lib/_vendor/statsd/__init__.py
@@ -14,7 +14,7 @@ log = logging.getLogger('rhodecode.stats
 
 def statsd_config(config, prefix='statsd.'):
     _config = {}
-    for key in config.keys():
+    for key in list(config.keys()):
         if key.startswith(prefix):
             _config[key[len(prefix):]] = config[key]
     return _config
@@ -24,9 +24,10 @@ def client_from_config(configuration, pr
     from pyramid.settings import asbool
 
     _config = statsd_config(configuration, prefix)
+    statsd_flag = _config.get('enabled')
     statsd_enabled = asbool(_config.pop('enabled', False))
     if not statsd_enabled:
-        log.debug('statsd client not enabled by statsd.enabled =  flag, skipping...')
+        log.debug('statsd client not enabled by statsd.enabled = %s flag, skipping...', statsd_flag)
         return
 
     host = _config.pop('statsd_host', HOST)
diff --git a/vcsserver/lib/ext_json.py b/vcsserver/lib/ext_json.py
--- a/vcsserver/lib/ext_json.py
+++ b/vcsserver/lib/ext_json.py
@@ -1,2 +1,14 @@
-# use orjson by default
-import orjson as json
+import json as stdlib_json
+
+try:
+    # we keep simplejson for having dump functionality still
+    # orjson doesn't support it
+    import simplejson as sjson
+except ImportError:
+    sjson = stdlib_json
+
+try:
+    import orjson
+    import orjson as json
+except ImportError:
+    json = stdlib_json
diff --git a/vcsserver/lib/logging_formatter.py b/vcsserver/lib/logging_formatter.py
--- a/vcsserver/lib/logging_formatter.py
+++ b/vcsserver/lib/logging_formatter.py
@@ -37,11 +37,19 @@ COLORS = {
 }
 
 
+def _inject_req_id(record, *args, **kwargs):
+    return record
+
+
+class ExceptionAwareFormatter(logging.Formatter):
+    pass
+
+
 class ColorFormatter(logging.Formatter):
 
     def format(self, record):
         """
-        Change record's levelname to use with COLORS enum
+        Changes record's levelname to use with COLORS enum
         """
         def_record = super().format(record)
 
@@ -51,3 +59,5 @@ class ColorFormatter(logging.Formatter):
 
         colored_record = ''.join([start, def_record, end])
         return colored_record
+
+