diff --git a/.github/workflows/deploy-pages.yml b/.github/workflows/deploy-pages.yml
new file mode 100644
index 00000000..db897826
--- /dev/null
+++ b/.github/workflows/deploy-pages.yml
@@ -0,0 +1,54 @@
+name: Deploy docs to GitHub Pages
+
+on:
+  push:
+    branches: [main]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+# Skip queued runs, but never interrupt an in-flight deploy: it can leave the site partial.
+concurrency:
+  group: pages
+  cancel-in-progress: false
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Zig
+        uses: mlugg/setup-zig@v2
+        with:
+          version: 0.16.0
+
+      - name: Build documentation
+        run: zig build docs
+
+      - name: Setup Pages
+        uses: actions/configure-pages@v5
+
+      - name: Upload Pages artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: zig-out/docs
+
+  deploy:
+    needs: build
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4
diff --git a/.github/workflows/tests.yaml b/.github/workflows/tests.yaml
new file mode 100644
index 00000000..4dc56e74
--- /dev/null
+++ b/.github/workflows/tests.yaml
@@ -0,0 +1,67 @@
+name: Tests
+
+on:
+  push:
+    branches: [main, dev]
+  pull_request:
+    branches: [main, dev]
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build_and_test:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 30
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Setup Zig
+        uses: mlugg/setup-zig@v2
+        with:
+          version: 0.16.0
+
+      - name: Build library
+        run: zig build
+
+      - name: Build documentation
+        if: matrix.os == 'ubuntu-latest'
+        run: zig build docs
+
+      - name: Run Zig tests
+        run: zig test -O ReleaseSafe ./src/test_min.zig
+
+  python_tests:
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Reclaim runner disk space
+        run: |
+          sudo rm -rf /usr/share/dotnet /usr/local/lib/android /opt/ghc
+          df -h /
+
+      - name: Setup Zig
+        uses: mlugg/setup-zig@v2
+        with:
+          version: 0.16.0
+
+      - name: Setup Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.12'
+
+      - name: Install package
+        run: pip install .
+
+      - name: Run Python tests
+        run: python -m pytest --pyargs riley.pytests
diff --git a/.gitignore b/.gitignore
index 7cae8828..859a5a8e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,6 +11,7 @@ out/
 bin/
 .*
 !.gitignore
+!.github/
 
 # Do not keep any large output directories with images or other output in them
 out/
diff --git a/build.zig b/build.zig
index 7cc21f45..75c91edd 100644
--- a/build.zig
+++ b/build.zig
@@ -51,11 +51,11 @@ pub fn build(b: *std.Build) void {
         optimize,
         build_options_module,
     );
-    b.installArtifact(shared_lib);
-    _ = b.addInstallHeaderFile(
+    shared_lib.installHeader(
         b.path("src/riley/cyth/riley.h"),
         "riley.h",
     );
+    b.installArtifact(shared_lib);
 
     const tests = [_]TestEntry{
         .{
@@ -237,6 +237,30 @@ pub fn build(b: *std.Build) void {
         install_step.dependOn(&install_artifact.step);
         bench_bins_step.dependOn(&install_artifact.step);
     }
+
+    // Rooted at the public API module, not shared_lib, whose generated wrapper
+    // root keeps its entry source private where autodoc cannot follow. A
+    // separate object also keeps doc generation out of normal builds. No
+    // build_options is injected here, so the -D config options have no effect:
+    // docs always describe the f64 / SIMD-on / fast-Newton build.
+    const docs_obj = b.addObject(.{
+        .name = "riley",
+        .root_module = b.createModule(.{
+            .root_source_file = b.path("src/riley/zig/riley.zig"),
+            .target = target,
+            .optimize = optimize,
+            .link_libc = true,
+        }),
+    });
+
+    const docs_install = b.addInstallDirectory(.{
+        .source_dir = docs_obj.getEmittedDocs(),
+        .install_dir = .prefix,
+        .install_subdir = "docs",
+    });
+
+    const docs_step = b.step("docs", "Generate API documentation");
+    docs_step.dependOn(&docs_install.step);
 }
 
 fn addRileySharedLibrary(