diff --git a/zerver/lib/subdomains.py b/zerver/lib/subdomains.py
index aa3a8f6ef0..c583a2af4b 100644
--- a/zerver/lib/subdomains.py
+++ b/zerver/lib/subdomains.py
@@ -56,6 +56,7 @@ def is_root_domain_available() -> bool:
 
 
 def is_static_or_current_realm_url(url: str, realm: Optional[Realm]) -> bool:
+    assert settings.STATIC_URL is not None
     split_url = urllib.parse.urlsplit(url)
     split_static_url = urllib.parse.urlsplit(settings.STATIC_URL)
 
diff --git a/zproject/computed_settings.py b/zproject/computed_settings.py
index e970abc0a5..ba3f369308 100644
--- a/zproject/computed_settings.py
+++ b/zproject/computed_settings.py
@@ -60,6 +60,7 @@ from .configured_settings import (
     SOCIAL_AUTH_SAML_ENABLED_IDPS,
     SOCIAL_AUTH_SAML_SECURITY_CONFIG,
     SOCIAL_AUTH_SUBDOMAIN,
+    STATIC_URL,
     STATSD_HOST,
     TORNADO_PORTS,
     USING_PGROONGA,
@@ -537,10 +538,11 @@ CAMO_KEY = get_secret("camo_key") if CAMO_URI != "" else None
 # STATIC CONTENT AND MINIFICATION SETTINGS
 ########################################################################
 
-if PRODUCTION or IS_DEV_DROPLET or os.getenv("EXTERNAL_HOST") is not None:
-    STATIC_URL = urljoin(ROOT_DOMAIN_URI, "/static/")
-else:
-    STATIC_URL = "http://localhost:9991/static/"
+if STATIC_URL is None:
+    if PRODUCTION or IS_DEV_DROPLET or os.getenv("EXTERNAL_HOST") is not None:
+        STATIC_URL = urljoin(ROOT_DOMAIN_URI, "/static/")
+    else:
+        STATIC_URL = "http://localhost:9991/static/"
 
 LOCAL_AVATARS_DIR = os.path.join(LOCAL_UPLOADS_DIR, "avatars") if LOCAL_UPLOADS_DIR else None
 LOCAL_FILES_DIR = os.path.join(LOCAL_UPLOADS_DIR, "files") if LOCAL_UPLOADS_DIR else None
diff --git a/zproject/default_settings.py b/zproject/default_settings.py
index 14c73fa8cb..9d5f9fb2c2 100644
--- a/zproject/default_settings.py
+++ b/zproject/default_settings.py
@@ -19,6 +19,8 @@ DEBUG = DEVELOPMENT
 
 EXTERNAL_HOST_WITHOUT_PORT = deport(EXTERNAL_HOST)
 
+STATIC_URL: Optional[str] = None
+
 # These settings are intended for the server admin to set.  We document them in
 # prod_settings_template.py, and in the initial /etc/zulip/settings.py on a new
 # install of the Zulip server.
diff --git a/zproject/dev_urls.py b/zproject/dev_urls.py
index 77c487be12..281250fb60 100644
--- a/zproject/dev_urls.py
+++ b/zproject/dev_urls.py
@@ -116,6 +116,7 @@ else:
         response["Access-Control-Allow-Origin"] = "*"
         return response
 
+    assert settings.STATIC_URL is not None
     urls += static(urlsplit(settings.STATIC_URL).path, view=serve_static)
 
 i18n_urls = [