diff --git a/docs/conf.py b/docs/conf.py
index a9dd3ee0c7850..c0b3d86e09330 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -3,6 +3,10 @@
 import sys
 from os import path
 
+
+# Centralize environment variables
+JINA_VERSION = os.environ.get('JINA_VERSION', None)
+
 sys.path.insert(0, path.abspath('..'))
 
 project = 'Jina'
@@ -15,7 +19,7 @@
 repo_dir = '../'
 
 try:
-    if 'JINA_VERSION' not in os.environ:
+    if not JINA_VERSION:
         pkg_name = 'jina'
         libinfo_py = path.join(repo_dir, pkg_name, '__init__.py')
         libinfo_content = open(libinfo_py, 'r', encoding='utf-8').readlines()
@@ -24,12 +28,13 @@
         ][0]
         exec(version_line)
     else:
-        __version__ = os.environ['JINA_VERSION']
+        __version__ = JINA_VERSION
 except FileNotFoundError:
     __version__ = '0.0.0'
 
 version = __version__
 release = __version__
+SPHINX_MULTIVERSION_VERSION = os.environ.get('SPHINX_MULTIVERSION_VERSION', version)
 
 templates_path = ['_templates']
 exclude_patterns = [
@@ -168,7 +173,7 @@
 ogp_description_length = 300
 ogp_type = 'website'
 ogp_site_name = (
-    f'Jina {os.environ.get("SPHINX_MULTIVERSION_VERSION", version)} Documentation'
+    f'Jina {SPHINX_MULTIVERSION_VERSION} Documentation'
 )
 
 ogp_custom_meta_tags = [
diff --git a/jina/constants.py b/jina/constants.py
index 4c3c2ad16693f..1ccc5d18ed43a 100644
--- a/jina/constants.py
+++ b/jina/constants.py
@@ -35,7 +35,7 @@
     'JINA_STREAMER_ARGS',
 )
 
-__default_host__ = _os.environ.get(
+__default_host__ = _os.getenv(
     'JINA_DEFAULT_HOST', '127.0.0.1' if __windows__ else '0.0.0.0'
 )
 __docker_host__ = 'host.docker.internal'
@@ -77,7 +77,6 @@
     '__windows__',
 ]
 
-__all__ = [_s for _s in dir() if not _s.startswith('_')]
-__all__.extend(_names_with_underscore)
+__all__ = [_s for _s in dir() if not _s.startswith('_')] + _names_with_underscore
 
 RAFT_TO_EXECUTOR_PORT = 100