diff --git a/setup/__init__.py b/setup/__init__.py
index 84fcab0a4e..a1476b4f3b 100644
--- a/setup/__init__.py
+++ b/setup/__init__.py
@@ -25,6 +25,7 @@ isdragonflybsd = 'dragonfly' in sys.platform
 isbsd = isnetbsd or isfreebsd or isdragonflybsd
 ishaiku = 'haiku1' in sys.platform
 islinux = not ismacos and not iswindows and not isbsd and not ishaiku
+is_ci = os.environ.get('CI', '').lower() == 'true'
 sys.setup_dir = os.path.dirname(os.path.abspath(__file__))
 SRC = os.path.abspath(os.path.join(os.path.dirname(sys.setup_dir), 'src'))
 sys.path.insert(0, SRC)
@@ -69,7 +70,7 @@ def download_securely(url):
     # We use curl here as on some OSes (OS X) when bootstrapping calibre,
     # python will be unable to validate certificates until after cacerts is
     # installed
-    if os.environ.get('CI') and iswindows:
+    if is_ci and iswindows:
         # curl is failing for wikipedia urls on CI (used for browser_data)
         from urllib.request import urlopen
         return urlopen(url).read()
@@ -211,7 +212,7 @@ class Command:
 
     def running(self, cmd):
         from setup.commands import command_names
-        if os.environ.get('CI'):
+        if is_ci:
             self.info('::group::' + command_names[cmd])
         self.info('\n*')
         self.info('* Running', command_names[cmd])
@@ -227,7 +228,7 @@ class Command:
         self.running(cmd)
         cmd.run(opts)
         self.info(f'* {command_names[cmd]} took {time.time() - st:.1f} seconds')
-        if os.environ.get('CI'):
+        if is_ci:
             self.info('::endgroup::')
 
     def run_all(self, opts):
diff --git a/setup/resources.py b/setup/resources.py
index ee60669b8c..60168ee92f 100644
--- a/setup/resources.py
+++ b/setup/resources.py
@@ -7,7 +7,6 @@ __docformat__ = 'restructuredtext en'
 
 import os, re, shutil, zipfile, glob, json, errno
 from zlib import compress
-is_ci = os.environ.get('CI', '').lower() == 'true'
 
 from setup import Command, basenames, __appname__, download_securely, dump_json
 from polyglot.builtins import codepoint_to_chr, itervalues, iteritems, only_unicode_recursive
diff --git a/setup/revendor.py b/setup/revendor.py
index b9786639ec..33f39412d1 100755
--- a/setup/revendor.py
+++ b/setup/revendor.py
@@ -7,9 +7,7 @@ import tarfile
 import time
 from io import BytesIO
 
-from setup import Command, download_securely
-
-is_ci = os.environ.get('CI', '').lower() == 'true'
+from setup import Command, download_securely, is_ci
 
 
 class ReVendor(Command):
diff --git a/setup/translations.py b/setup/translations.py
index 4a1764e282..c764ff4ad7 100644
--- a/setup/translations.py
+++ b/setup/translations.py
@@ -10,10 +10,9 @@ from collections import defaultdict
 from locale import normalize as normalize_locale
 from functools import partial
 
-from setup import Command, __appname__, __version__, require_git_master, build_cache_dir, edit_file, dump_json
+from setup import Command, __appname__, __version__, require_git_master, build_cache_dir, edit_file, dump_json, is_ci
 from setup.parallel_build import batched_parallel_jobs
 from polyglot.builtins import codepoint_to_chr, iteritems
-is_ci = os.environ.get('CI', '').lower() == 'true'
 
 
 def qt_sources():