diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index adf055dd1..1227636b8 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -21,6 +21,6 @@ sphinx:
 # Optionally declare the Python requirements required to build your docs
 python:
   install:
+    - requirements: docs/requirements.txt
     - method: setuptools
       path: .
-    - requirements: docs/requirements.txt
diff --git a/docs/requirements.txt b/docs/requirements.txt
index 401075189..febb6488b 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,3 +1,5 @@
 sphinx_immaterial[json,clang-format,keys,cpp]
 sphinxcontrib-details-directive
 sphinx-jinja
+pydantic
+importlib_resources
diff --git a/requirements.txt b/requirements.txt
index d815bf5ee..a7fc9e53d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,3 +4,4 @@ pydantic
 typing-extensions
 appdirs
 requests
+importlib-resources
diff --git a/setup.py b/setup.py
index 44a850d28..50d3fbafc 100644
--- a/setup.py
+++ b/setup.py
@@ -30,6 +30,12 @@
 import setuptools.command.develop
 import setuptools.command.install
 import setuptools.command.sdist
+from sphinx_immaterial.google_fonts import install_google_fonts
+
+from importlib_resources import files
+from sphinx_immaterial import resources
+
+from sphinx_immaterial import DEFAULT_THEME_OPTIONS
 
 with open("requirements.txt", encoding="utf-8") as reqs:
     REQUIREMENTS = [reqs.readlines()]
@@ -146,6 +152,11 @@ def run(self):
         target = {"min": "build", "dev": "build:dev"}
 
         try:
+            install_google_fonts(
+                files(resources),
+                files(resources),
+                DEFAULT_THEME_OPTIONS["font"].values(),
+            )
             tgt = target[self.bundle_type]
             node_modules_path = os.path.join(root_dir, "node_modules")
             if self.skip_npm_reinstall and os.path.exists(node_modules_path):
@@ -187,6 +198,8 @@ def run(self):
             "*.html",
             "custom_admonitions.css",
             "theme.conf",
+            "resources/*.response",
+            "resources/*/*.response",
         ],
         "sphinx_immaterial.apidoc.cpp.cppreference_data": ["*.xml"],
     },
diff --git a/sphinx_immaterial/external_resource_cache.py b/sphinx_immaterial/external_resource_cache.py
index 0bbce2bf3..b5edbf2ea 100644
--- a/sphinx_immaterial/external_resource_cache.py
+++ b/sphinx_immaterial/external_resource_cache.py
@@ -3,6 +3,7 @@
 import os
 import tempfile
 from typing import Dict, Optional
+from importlib_resources import files
 
 import appdirs
 import requests
@@ -10,6 +11,8 @@
 import sphinx.config
 import sphinx.util.logging
 
+from sphinx_immaterial import resources
+
 logger = sphinx.util.logging.getLogger(__name__)
 
 
@@ -22,13 +25,23 @@ def get_url(
     req_json_encoded = json.dumps(req_json).encode("utf-8")
     req_key = hashlib.sha256(req_json_encoded).hexdigest()
 
-    resp_path = os.path.join(cache_dir, f"{req_key}.response")
+    # First try the in-module resources
+    mod_res_path = files(resources) / f"{req_key}.response"
     try:
-        with open(resp_path, "rb") as f:
+        with open(str(mod_res_path), "rb") as f:
             return f.read()
     except FileNotFoundError:
         pass
 
+    # Secondly, look at the cache
+    resp_path = os.path.join(cache_dir, f"{req_key}.response")
+    if cache_dir:
+        try:
+            with open(resp_path, "rb") as f:
+                return f.read()
+        except FileNotFoundError:
+            pass
+
     logger.info("Fetching: %s with %r", url, headers)
     r = requests.get(  # pylint: disable=missing-timeout
         url, headers=headers, stream=True
@@ -37,6 +50,9 @@ def get_url(
 
     response_content = r.content
 
+    if not cache_dir:
+        return response_content
+
     # Write request.
     req_path = os.path.join(cache_dir, f"{req_key}.request")
     os.makedirs(cache_dir, exist_ok=True)
diff --git a/sphinx_immaterial/google_fonts.py b/sphinx_immaterial/google_fonts.py
index de2261a5d..92731d326 100644
--- a/sphinx_immaterial/google_fonts.py
+++ b/sphinx_immaterial/google_fonts.py
@@ -60,11 +60,25 @@ def _adjust_css_urls(css_content: bytes, renamed_fonts: Dict[str, str]) -> str:
 _TTF_FONT_PATHS_KEY = "sphinx_immaterial_ttf_font_paths"
 
 
-def add_google_fonts(app: sphinx.application.Sphinx, fonts: List[str]):
-    cache_dir = os.path.join(get_cache_dir(app), "google_fonts")
-    static_dir = os.path.join(app.outdir, "_static")
-    # _static path
-    font_dir = os.path.join(static_dir, "fonts")
+def install_google_fonts(cache_dir: str, font_dir: str, fonts: List[str]):
+    """
+    Saves google fonts to given directory.
+
+    Firstly, it tries to load fonts from cache directory.
+    If it fails, it downloads fonts from remote locations.
+
+    The font files are saved to font_dir.
+
+    Parameters
+    ----------
+    cache_dir : str
+        Directory with cached downloaded files.
+        If cache_dir is empty, skip checking cache
+    font_dir : str
+        Target directory where fonts are saved
+    fonts : List[str]
+        List of fonts to save
+    """
     os.makedirs(font_dir, exist_ok=True)
 
     with concurrent.futures.ThreadPoolExecutor(max_workers=32) as executor:
@@ -166,7 +180,16 @@ async def do_fetch():
             css_content = dict(zip(css_future_keys, await asyncio.gather(*css_futures)))
             return css_content
 
-        css_content = asyncio.run(do_fetch())
+        return asyncio.run(do_fetch())
+
+
+def add_google_fonts(app: sphinx.application.Sphinx, fonts: List[str]):
+    cache_dir = os.path.join(get_cache_dir(app), "google_fonts")
+    static_dir = os.path.join(app.outdir, "_static")
+    # _static path
+    font_dir = os.path.join(static_dir, "fonts")
+
+    css_content = install_google_fonts(cache_dir, font_dir, fonts)
 
     # Write fonts css file
     ttf_font_paths = {}
diff --git a/sphinx_immaterial/resources/__init__.py b/sphinx_immaterial/resources/__init__.py
new file mode 100644
index 000000000..1b5292084
--- /dev/null
+++ b/sphinx_immaterial/resources/__init__.py
@@ -0,0 +1,3 @@
+"""
+Module holding additional resources, i.e. built-in fonts
+"""