feat: template index.html meta tags via Jinja from the Python build

.gitignore

@@ -225,3 +225,6 @@ node_modules/
 .DS_Store
 .superpowers/
 .playwright-mcp/
+
+# Generated by `contributor-network build` from python/contributor_network/templates/index.html.j2
+/index.html

README.md

@@ -119,6 +119,16 @@ Edit `config.toml` to configure:
 - **contributors.devseed**: Current DevSeed employees (format: `github_username = "Display Name"`)
 - **contributors.alumni**: Friends and alumni (commented out by default)
 
+### SEO / meta tags
+
+The following `config.toml` fields populate `<meta>` tags in `index.html` at build time:
+
+- `og_url` — the canonical URL for the deployed site (used in `og:url`)
+- `og_image` — the URL to the social-share image (used in `og:image`)
+- `theme_color` — the browser theme color (used in `<meta name="theme-color">`); defaults to `branding.primary_color` if unset
+
+`index.html` is rendered from [`python/contributor_network/templates/index.html.j2`](./python/contributor_network/templates/index.html.j2) by `contributor-network build` and is gitignored. To change page structure, edit the template (not the generated file). Forks can override the meta-tag values without modifying the template.
+
 ## Branding
 
 This visualization uses the Development Seed brand colors:

config.toml

@@ -3,6 +3,9 @@ title = "The Development Seed Contributor Network"
 description = "An interactive visualization of contributors to Development Seed code and their connections to other repositories"
 organization_name = "Development Seed"
 organization_nickname = "DevSeed"
+og_url = "https://developmentseed.org/contributor-network/"
+og_image = "https://developmentseed.org/contributor-network/site-image.jpg"
+theme_color = "#CF3F02"
 
 # Repositories
 repositories = [

pyproject.toml

@@ -6,6 +6,7 @@ readme = "README.md"
 requires-python = ">=3.13"
 dependencies = [
     "click>=8.2.1",
+    "jinja2>=3.1.4",
     "pydantic>=2.11.9",
     "pygithub>=2.8.1",
 ]

python/contributor_network/cli.py

@@ -6,11 +6,32 @@
 
 import click
 from github import Auth, Github
+from jinja2 import Environment, FileSystemLoader, StrictUndefined
 
 from .client import Client
 from .config import Config
 from .models import Link, Repository
 
+TEMPLATES_DIR = Path(__file__).absolute().parent / "templates"
+
+
+def render_index_html(config: Config) -> str:
+    """Render the index.html template from a Config."""
+    env = Environment(
+        loader=FileSystemLoader(TEMPLATES_DIR),
+        autoescape=True,
+        undefined=StrictUndefined,
+    )
+    template = env.get_template("index.html.j2")
+    return template.render(
+        organization_name=config.organization_name,
+        description=config.description,
+        og_url=config.og_url,
+        og_image=config.og_image,
+        theme_color=config.resolved_theme_color,
+    )
+
+
 ROOT = Path(__file__).absolute().parents[2]
 DEFAULT_CONFIG_PATH = "config.toml"
 directory = click.option(
@@ -153,6 +174,9 @@ def build(directory: Path, config_path: str | None, all_contributors: bool) -> N
     )
     print(f"Generated config.json in {directory}")
 
+    (ROOT / "index.html").write_text(render_index_html(config))
+    print(f"Generated index.html at {ROOT / 'index.html'}")
+
 
 @main.command()
 @config

python/contributor_network/config.py

@@ -47,6 +47,14 @@ class Config(BaseModel):
     contributors: dict[str, dict[str, str]]  # Nested: {"core": {...}, "alumni": {...}}
     contributor_padding: int = 40
     branding: BrandingConfig = BrandingConfig()
+    og_url: str = ""
+    og_image: str = ""
+    theme_color: str = ""
+
+    @property
+    def resolved_theme_color(self) -> str:
+        """Theme color falls back to branding.primary_color when unset."""
+        return self.theme_color or self.branding.primary_color
 
     @property
     def core_contributors(self) -> dict[str, str]:

index.html → python/contributor_network/templates/index.html.j2

@@ -4,16 +4,16 @@
     <meta charset="utf-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
 
-    <title>Contributor Network</title>
+    <title>The {{ organization_name }} Contributor Network</title>
 
-    <meta name="author" content="Development Seed">
-    <meta name="description" content="An interactive visualization of contributors and their connections to repositories">
-    <meta name="theme-color" content="#cf3f02">
-    <meta property="og:title" content="The Development Seed Contributor Network">
-    <meta property="og:url" content="https://developmentseed.org/contributor-network/">
+    <meta name="author" content="{{ organization_name }}">
+    <meta name="description" content="{{ description }}">
+    <meta name="theme-color" content="{{ theme_color }}">
+    <meta property="og:title" content="The {{ organization_name }} Contributor Network">
+    <meta property="og:url" content="{{ og_url }}">
     <meta property="og:type" content="article">
     <meta property="og:locale" content="en_US">
-    <meta property="og:image" content="https://developmentseed.org/contributor-network/site-image.jpg">
+    <meta property="og:image" content="{{ og_image }}">
     <meta property="og:image:type" content="image/jpeg">
     <meta property="og:image:width" content="1200">
     <meta property="og:image:height" content="800">

python/tests/test_config.py

@@ -5,3 +5,29 @@
 
 def test_config() -> None:
     Config.from_toml(Path(__file__).parents[2] / "config.toml")
+
+
+def test_config_meta_fields_have_defaults():
+    config = Config.from_toml(Path(__file__).parents[2] / "config.toml")
+    assert config.og_url == "https://developmentseed.org/contributor-network/"
+    assert (
+        config.og_image
+        == "https://developmentseed.org/contributor-network/site-image.jpg"
+    )
+    assert config.theme_color == "#CF3F02"
+
+
+def test_config_meta_fields_optional_in_toml(tmp_path):
+    minimal = tmp_path / "minimal.toml"
+    minimal.write_text(
+        'title = "X"\n'
+        'description = "Y"\n'
+        'organization_name = "Z"\n'
+        "repositories = []\n"
+        "[contributors.core]\n"
+    )
+    config = Config.from_toml(minimal)
+    assert config.og_url == ""
+    assert config.og_image == ""
+    assert config.resolved_theme_color == "#CF3F02"
+    assert config.theme_color == ""