diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 4230068..e854e95 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -39,6 +39,10 @@ jobs:
         with:
           python-version: ${{ matrix.python-version }}
           uv-dependency-install-flags: "--all-extras --group docs"
+      - name: Install Graphviz
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y graphviz
       - name: docs
         run: |
           uv run --no-sync mkdocs build --strict
diff --git a/.gitignore b/.gitignore
index 1f87080..6722197 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,6 +17,8 @@ docs/fgen/api/*
 !docs/fgen/api/.gitkeep
 docs/fgen-runtime/api/*
 !docs/fgen-runtime/api/.gitkeep
+docs/fortran-api/*
+!docs/fortran-api/.gitkeep
 
 # Databases
 *.db
diff --git a/changelog/16.docs.md b/changelog/16.docs.md
new file mode 100644
index 0000000..6611726
--- /dev/null
+++ b/changelog/16.docs.md
@@ -0,0 +1 @@
+Added documentation of the Fortran back-end/API using [ford](https://forddocs.readthedocs.io/en/stable/)
diff --git a/docs/NAVIGATION.md b/docs/NAVIGATION.md
index 46f9460..fb48646 100644
--- a/docs/NAVIGATION.md
+++ b/docs/NAVIGATION.md
@@ -13,4 +13,5 @@ See https://oprypin.github.io/mkdocs-literate-nav/
     - [Dependency pinning and testing](further-background/dependency-pinning-and-testing.md)
 - [Development](development.md)
 - [API reference](api/example_fgen_basic/)
+- [Fortran API](fortran-api/home.html)
 - [Changelog](changelog.md)
diff --git a/docs/development.md b/docs/development.md
index 832dfe1..65472c8 100644
--- a/docs/development.md
+++ b/docs/development.md
@@ -31,6 +31,35 @@ Try and keep your merge requests as small as possible
 This makes life much easier for reviewers
 which allows contributions to be accepted at a faster rate.
 
+## Using uv with a compiled package
+
+Using uv with a compiled package is a bit more painful.
+Whenever you do `uv run` or `uv sync` or similar,
+uv tries to install the compiled package as an editable package.
+This can then cause issues on later calls to `uv run` or `uv sync`
+as having compiled packages as editable packages doesn't really work
+(you get errors like
+`ImportError: re-building the <package-name> meson-python editable wheel package failed`).
+The way around this is to:
+
+1. use the `--no-editable` flag with `uv sync`
+    so that uv doesn't do an editable install
+1. use the `--no-sync` flag with `uv run`
+    (and any other command that takes this flag)
+    so that `uv` doesn't try and re-build packages
+1. use the `--reinstall-package` flag with `uv run`
+    whenever you want to be sure that the latest changes
+    will be used for running a command
+    (yes, this makes running things slower,
+    but slower and reliable is better than broken)
+
+We include these flags in our `Makefile` and GitHub workflows
+if you want to see them in use.
+
+If you forget and run `uv run ...` in your terminal.
+The easiest solution seems to be to delete your virtual environment entirely and start again.
+We haven't found a way to get out of an accidental editable install.
+
 ## Language
 
 We use British English for our development.
diff --git a/docs/fortran-api/.gitkeep b/docs/fortran-api/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/docs/gen_fortran_api.py b/docs/gen_fortran_api.py
new file mode 100644
index 0000000..2fadef0
--- /dev/null
+++ b/docs/gen_fortran_api.py
@@ -0,0 +1,63 @@
+"""
+Drive Ford to create Fortran API docs
+"""
+
+from __future__ import annotations
+
+import shutil
+import subprocess
+from pathlib import Path
+
+import mkdocs_gen_files
+
+REPO_ROOT = Path(__file__).parents[1]
+
+FORD_OUTPUT_DIR = Path("docs") / "fortran-api"
+
+ford = shutil.which("ford")
+if ford is None:
+    msg = "Could not find FORD executable"
+    raise AssertionError(msg)
+
+subprocess.run(  # noqa: S603
+    [ford, "ford_config.md", "--output_dir", str(FORD_OUTPUT_DIR)],
+    check=True,
+)
+
+# Copy files across using mkdocs_gen_files
+# so it knows to include the files in the final docs.
+for entry in (REPO_ROOT / FORD_OUTPUT_DIR).rglob("*"):
+    if not entry.is_file():
+        continue
+
+    with open(entry, "rb") as fh:
+        contents = fh.read()
+
+    target_file = entry.relative_to(REPO_ROOT / "docs")
+    with mkdocs_gen_files.open(target_file, "wb") as fh:
+        fh.write(contents)
+
+    if target_file.name == "index.html":
+        # Also create a home.html file which we can point to from `NAVIGATION.md`.
+        # I don't know why just pointing to `index.html` doesn't work,
+        # but it doesn't (maybe cause `index.html` is a special name?).
+        target_file = target_file.parent / "home.html"
+
+        with mkdocs_gen_files.open(target_file, "wb") as fh:
+            fh.write(contents)
+
+# # If we want to move back to using literate-nav for maanging our navigation,
+# # also for the Fortran bits, we'll need something like the below
+# # and adjustments to the existing `NAVIGATION.md`.
+# with mkdocs_gen_files.open(
+#     (FORD_OUTPUT_DIR).relative_to("docs") / "NAVIGATION.md", "w"
+# ) as fh:
+#     fh.writelines("* [example_fgen_basic](home.html)")
+
+# Remove the ford files (which were just copied)
+shutil.rmtree(REPO_ROOT / FORD_OUTPUT_DIR)
+
+# Put back the gitkeep file
+gitkeep = REPO_ROOT / FORD_OUTPUT_DIR / ".gitkeep"
+gitkeep.parent.mkdir()
+gitkeep.touch()
diff --git a/docs/index.md b/docs/index.md
index 1fe13ca..e26f209 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -1 +1,10 @@
 ---8<--- "README.md:description"
+
+## API docs
+
+Our Python API is documented in [API][example_fgen_basic_1].
+The Fortran API is documented in [Fortran API](./fortran-api/).
+At present, the Fortran API docs are a sub-website so you can navigate to them
+but there are no buttons to navigate back to the main docs page
+(so you have to instead return yourself by re-entering the URL
+or pressing back, sorry, we hope to improve this in future).
diff --git a/environment-docs-conda-base.yml b/environment-docs-conda-base.yml
index 0d2d79b..8cc26e0 100644
--- a/environment-docs-conda-base.yml
+++ b/environment-docs-conda-base.yml
@@ -9,3 +9,4 @@ dependencies:
   - pip
   - gcc
   - gfortran
+  - graphviz
diff --git a/ford_config.md b/ford_config.md
new file mode 100644
index 0000000..92adf44
--- /dev/null
+++ b/ford_config.md
@@ -0,0 +1,8 @@
+---
+project: Example fgen - basic
+author: TODO align this with pyproject.toml
+src_dir: src
+graph: true
+---
+
+API docs for Fortran components!
diff --git a/mkdocs.yml b/mkdocs.yml
index d7d5c78..7c7421d 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -35,6 +35,7 @@ plugins:
   - gen-files:
       scripts:
         - docs/gen_doc_stubs.py
+        - docs/gen_fortran_api.py
   # Make the navigation easier to handle/auto-generate if we wish
   # https://oprypin.github.io/mkdocs-literate-nav/
   - literate-nav:
@@ -56,7 +57,7 @@ plugins:
       allow_errors: false
       # theme: dark
       include_source: True
-      ignore: ["*.ipynb", "*.md", "docs/gen_doc_stubs.py"]
+      ignore: ["*.ipynb", "*.md", "docs/gen_doc_stubs.py", "docs/gen_fortran_api.py"]
       remove_tag_config:
         remove_input_tags:
           - remove_input
diff --git a/pyproject.toml b/pyproject.toml
index ac8fd09..0246127 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -77,6 +77,8 @@ docs = [
     # Key dependencies
     # ----------------
     "attrs>=25.3.0",
+    "ford>=6.0.1",
+    "graphviz>=0.21",
     "mkdocs-autorefs>=1.4.2",
     "mkdocs-gen-files>=0.5.0",
     "mkdocs-literate-nav>=0.6.2",
diff --git a/requirements-docs-locked.txt b/requirements-docs-locked.txt
index b3ea620..1eb5ec2 100644
--- a/requirements-docs-locked.txt
+++ b/requirements-docs-locked.txt
@@ -29,8 +29,10 @@ exceptiongroup==1.3.0 ; python_full_version < '3.11'
 executing==2.1.0
 fastjsonschema==2.21.1
 fonttools==4.59.0
+ford==6.1.13
 fqdn==1.5.1
 ghp-import==2.1.0
+graphviz==0.21
 griffe==1.11.0
 h11==0.14.0
 httpcore==1.0.7
@@ -63,6 +65,7 @@ jupytext==1.17.2
 kiwisolver==1.4.7 ; python_full_version < '3.10'
 kiwisolver==1.4.9 ; python_full_version >= '3.10'
 markdown==3.7
+markdown-include==0.8.1
 markdown-it-py==3.0.0
 markupsafe==3.0.2
 matplotlib==3.9.4 ; python_full_version < '3.10'
@@ -112,6 +115,7 @@ pymdown-extensions==10.16.1
 pyparsing==3.2.3
 python-dateutil==2.9.0.post0
 python-json-logger==3.2.1
+python-markdown-math==0.9
 pywin32==308 ; platform_python_implementation != 'PyPy' and sys_platform == 'win32'
 pywinpty==2.0.14 ; os_name == 'nt'
 pyyaml==6.0.2
@@ -132,7 +136,9 @@ stack-data==0.6.3
 terminado==0.18.1
 tinycss2==1.4.0
 tomli==2.2.1 ; python_full_version < '3.11'
+toposort==1.10
 tornado==6.4.2
+tqdm==4.67.1
 traitlets==5.14.3
 types-python-dateutil==2.9.0.20241206
 typing-extensions==4.12.2
diff --git a/uv.lock b/uv.lock
index 15d032b..4d6a544 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1,5 +1,5 @@
 version = 1
-revision = 3
+revision = 2
 requires-python = ">=3.9"
 resolution-markers = [
     "python_full_version >= '3.13' and sys_platform == 'win32'",
@@ -764,7 +764,9 @@ plots = [
 [package.dev-dependencies]
 all-dev = [
     { name = "attrs" },
+    { name = "ford" },
     { name = "fprettify" },
+    { name = "graphviz" },
     { name = "jupyterlab" },
     { name = "jupytext" },
     { name = "liccheck" },
@@ -806,6 +808,8 @@ dev = [
 ]
 docs = [
     { name = "attrs" },
+    { name = "ford" },
+    { name = "graphviz" },
     { name = "jupyterlab" },
     { name = "jupytext" },
     { name = "mkdocs" },
@@ -845,7 +849,9 @@ provides-extras = ["plots", "full"]
 [package.metadata.requires-dev]
 all-dev = [
     { name = "attrs", specifier = ">=25.3.0" },
+    { name = "ford", specifier = ">=6.0.1" },
     { name = "fprettify", specifier = ">=0.3.7" },
+    { name = "graphviz", specifier = ">=0.21" },
     { name = "jupyterlab", specifier = ">=4.4.5" },
     { name = "jupytext", specifier = ">=1.17.2" },
     { name = "liccheck", specifier = ">=0.9.2" },
@@ -887,6 +893,8 @@ dev = [
 ]
 docs = [
     { name = "attrs", specifier = ">=25.3.0" },
+    { name = "ford", specifier = ">=6.0.1" },
+    { name = "graphviz", specifier = ">=0.21" },
     { name = "jupyterlab", specifier = ">=4.4.5" },
     { name = "jupytext", specifier = ">=1.17.2" },
     { name = "mkdocs", specifier = ">=1.6.1" },
@@ -1020,6 +1028,26 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/d0/9c/df0ef2c51845a13043e5088f7bb988ca6cd5bb82d5d4203d6a158aa58cf2/fonttools-4.59.0-py3-none-any.whl", hash = "sha256:241313683afd3baacb32a6bd124d0bce7404bc5280e12e291bae1b9bba28711d", size = 1128050, upload-time = "2025-07-16T12:04:52.687Z" },
 ]
 
+[[package]]
+name = "ford"
+version = "6.1.13"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "beautifulsoup4" },
+    { name = "graphviz" },
+    { name = "jinja2" },
+    { name = "markdown" },
+    { name = "markdown-include" },
+    { name = "pygments" },
+    { name = "python-markdown-math" },
+    { name = "toposort" },
+    { name = "tqdm" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/1c/80/a8750198772c8647aa2c8d1459d5d8dbedd317a2ba18fdad73802073e1d5/FORD-6.1.13.tar.gz", hash = "sha256:95b743ea25c5a9c6a9e13db3633e04f91e11d1debb69f48ca3ef7fefc51f0559", size = 5849087, upload-time = "2022-07-01T15:19:31.983Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/b3/49/00fb42b10bcb6b241f3c29248afa55000554aa05fb67588a4f2616361953/FORD-6.1.13-py3-none-any.whl", hash = "sha256:701ecd4b8744714a50cd31a8b49a95a85d647716b9d971a60ab1b58c53032048", size = 666132, upload-time = "2022-07-01T15:19:29.65Z" },
+]
+
 [[package]]
 name = "fprettify"
 version = "0.3.7"
@@ -1053,6 +1081,15 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/f7/ec/67fbef5d497f86283db54c22eec6f6140243aae73265799baaaa19cd17fb/ghp_import-2.1.0-py3-none-any.whl", hash = "sha256:8337dd7b50877f163d4c0289bc1f1c7f127550241988d568c1db512c4324a619", size = 11034, upload-time = "2022-05-02T15:47:14.552Z" },
 ]
 
+[[package]]
+name = "graphviz"
+version = "0.21"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/f8/b3/3ac91e9be6b761a4b30d66ff165e54439dcd48b83f4e20d644867215f6ca/graphviz-0.21.tar.gz", hash = "sha256:20743e7183be82aaaa8ad6c93f8893c923bd6658a04c32ee115edb3c8a835f78", size = 200434, upload-time = "2025-06-15T09:35:05.824Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/91/4c/e0ce1ef95d4000ebc1c11801f9b944fa5910ecc15b5e351865763d8657f8/graphviz-0.21-py3-none-any.whl", hash = "sha256:54f33de9f4f911d7e84e4191749cac8cc5653f815b06738c54db9a15ab8b1e42", size = 47300, upload-time = "2025-06-15T09:35:04.433Z" },
+]
+
 [[package]]
 name = "griffe"
 version = "1.11.0"
@@ -1785,6 +1822,18 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/3f/08/83871f3c50fc983b88547c196d11cf8c3340e37c32d2e9d6152abe2c61f7/Markdown-3.7-py3-none-any.whl", hash = "sha256:7eb6df5690b81a1d7942992c97fad2938e956e79df20cbc6186e9c3a77b1c803", size = 106349, upload-time = "2024-08-16T15:55:16.176Z" },
 ]
 
+[[package]]
+name = "markdown-include"
+version = "0.8.1"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "markdown" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/ad/d8/66bf162fe6c1adb619f94a6da599323eecacf15b6d57469d0fd0421c10df/markdown-include-0.8.1.tar.gz", hash = "sha256:1d0623e0fc2757c38d35df53752768356162284259d259c486b4ab6285cdbbe3", size = 21873, upload-time = "2023-02-07T09:47:26.608Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/d7/e2/c4d20b21a05fe0fee571649cebc05f7f72e80b1a743f932e7326125e6c9e/markdown_include-0.8.1-py3-none-any.whl", hash = "sha256:32f0635b9cfef46997b307e2430022852529f7a5b87c0075c504283e7cc7db53", size = 18837, upload-time = "2023-02-07T09:47:25.03Z" },
+]
+
 [[package]]
 name = "markdown-it-py"
 version = "3.0.0"
@@ -2976,6 +3025,18 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/4b/72/2f30cf26664fcfa0bd8ec5ee62ec90c03bd485e4a294d92aabc76c5203a5/python_json_logger-3.2.1-py3-none-any.whl", hash = "sha256:cdc17047eb5374bd311e748b42f99d71223f3b0e186f4206cc5d52aefe85b090", size = 14924, upload-time = "2024-12-16T06:48:03.25Z" },
 ]
 
+[[package]]
+name = "python-markdown-math"
+version = "0.9"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "markdown" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/4c/68/fbea05ec6fb318bdcf56ea47596605614554f51d77bfd14f6fb481139ad8/python_markdown_math-0.9.tar.gz", hash = "sha256:567395553dc4941e79b3789a1096dcabb3fda9539d150d558ef3507948b264a3", size = 8680, upload-time = "2025-04-10T10:10:31.84Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/eb/68/ecf3535c40845de2efd8ac2d092dd5fca0868219fa3684d9e58ef7abeece/python_markdown_math-0.9-py3-none-any.whl", hash = "sha256:ac9932df517a5c0f6d01c56e7a44d065eca4a420893ac45f7a6937c67cb41e86", size = 6046, upload-time = "2025-04-10T10:10:30.318Z" },
+]
+
 [[package]]
 name = "pywin32"
 version = "308"
@@ -3523,6 +3584,15 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/c7/18/c86eb8e0202e32dd3df50d43d7ff9854f8e0603945ff398974c1d91ac1ef/tomli_w-1.2.0-py3-none-any.whl", hash = "sha256:188306098d013b691fcadc011abd66727d3c414c571bb01b1a174ba8c983cf90", size = 6675, upload-time = "2025-01-15T12:07:22.074Z" },
 ]
 
+[[package]]
+name = "toposort"
+version = "1.10"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/69/19/8e955d90985ecbd3b9adb2a759753a6840da2dff3c569d412b2c9217678b/toposort-1.10.tar.gz", hash = "sha256:bfbb479c53d0a696ea7402601f4e693c97b0367837c8898bc6471adfca37a6bd", size = 11132, upload-time = "2023-02-27T13:59:51.834Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/f6/17/57b444fd314d5e1593350b9a31d000e7411ba8e17ce12dc7ad54ca76b810/toposort-1.10-py3-none-any.whl", hash = "sha256:cbdbc0d0bee4d2695ab2ceec97fe0679e9c10eab4b2a87a9372b929e70563a87", size = 8500, upload-time = "2023-02-25T20:07:06.538Z" },
+]
+
 [[package]]
 name = "tornado"
 version = "6.4.2"
@@ -3557,6 +3627,18 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/93/1b/2f7b88506e22d9798c139261af4946865c0787cfa345514ca3c70173a9cc/towncrier-24.8.0-py3-none-any.whl", hash = "sha256:9343209592b839209cdf28c339ba45792fbfe9775b5f9c177462fd693e127d8d", size = 56981, upload-time = "2024-08-23T14:52:26.659Z" },
 ]
 
+[[package]]
+name = "tqdm"
+version = "4.67.1"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "colorama", marker = "sys_platform == 'win32'" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/a8/4b/29b4ef32e036bb34e4ab51796dd745cdba7ed47ad142a9f4a1eb8e0c744d/tqdm-4.67.1.tar.gz", hash = "sha256:f8aef9c52c08c13a65f30ea34f4e5aac3fd1a34959879d7e59e63027286627f2", size = 169737, upload-time = "2024-11-24T20:12:22.481Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/d0/30/dc54f88dd4a2b5dc8a0279bdd7270e735851848b762aeb1c1184ed1f6b14/tqdm-4.67.1-py3-none-any.whl", hash = "sha256:26445eca388f82e72884e0d580d5464cd801a3ea01e63e5601bdff9ba6a48de2", size = 78540, upload-time = "2024-11-24T20:12:19.698Z" },
+]
+
 [[package]]
 name = "traitlets"
 version = "5.14.3"