diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
new file mode 100644
index 0000000..9ddd432
--- /dev/null
+++ b/.github/workflows/build.yml
@@ -0,0 +1,46 @@
+name: Build
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  examples:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    timeout-minutes: 30
+    container: ghcr.io/grumpycoders/pcsx-redux-build:latest
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: recursive
+          set-safe-directory: true
+          persist-credentials: false
+
+      - name: OpenBIOS
+        run: make -C third_party/nugget/openbios -j2 all
+
+      - name: Examples
+        run: |
+          for d in examples/*/; do
+            echo "::group::$d"
+            make -C "$d" -j2 all BOOK_CI=true
+            echo "::endgroup::"
+          done
+
+      - name: Emulator
+        # The dev channel AppImage, extracted because a runner has no FUSE.
+        run: |
+          curl -sL -o pcsx-redux.zip https://distrib.app/pub/org/pcsx-redux/project/dev-linux-x64/latest
+          unzip -q pcsx-redux.zip
+          ./PCSX-Redux-*.AppImage --appimage-extract > /dev/null
+
+      - name: Boot every example
+        run: ci/run-examples.sh "$GITHUB_WORKSPACE/squashfs-root/AppRun" third_party/nugget/openbios/openbios.bin
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..c59337d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+*.o
+*.dep
+*.elf
+*.map
+*.ps-exe
diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..d96a991
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "third_party/nugget"]
+	path = third_party/nugget
+	url = https://github.com/pcsx-redux/nugget.git
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..2ad449e
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 the learn authors
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/ci/ci.hh b/ci/ci.hh
new file mode 100644
index 0000000..064dce5
--- /dev/null
+++ b/ci/ci.hh
@@ -0,0 +1,22 @@
+// Hooks for the CI run that boots every example in PCSX-Redux. They compile
+// to nothing unless the example is built with BOOK_CI=true, so the examples
+// read the same as they would without them.
+
+#pragma once
+
+#ifdef BOOK_CI
+#include "common/hardware/pcsxhw.h"
+#include "common/syscalls/syscalls.h"
+
+// Print the line the CI script greps for, then leave the emulator with
+// exit code 0. On hardware pcsx_exit is an ignored store.
+#define BOOK_CI_PASS(fmt, ...)                                  \
+    do {                                                        \
+        ramsyscall_printf("BOOK-PASS " fmt "\n", ##__VA_ARGS__); \
+        pcsx_exit(0);                                           \
+    } while (0)
+#else
+#define BOOK_CI_PASS(fmt, ...) \
+    do {                       \
+    } while (0)
+#endif
diff --git a/ci/run-examples.sh b/ci/run-examples.sh
new file mode 100755
index 0000000..3ea229d
--- /dev/null
+++ b/ci/run-examples.sh
@@ -0,0 +1,63 @@
+#!/bin/bash
+# Boot every example in PCSX-Redux and grade each on its BOOK-PASS line,
+# never on the absence of a failure.
+#
+#   ci/run-examples.sh <pcsx-redux or its AppRun> <openbios.bin>
+#
+# Run from the repository root after building the examples with
+# BOOK_CI=true. Every examples/*/ directory has to be listed below, so a new
+# example cannot be left out of the run by accident.
+
+set -u
+
+if [ -z "${DISPLAY:-}" ]; then
+    exec xvfb-run -a "$0" "$@"
+fi
+
+EMU=${1:?usage: $0 <pcsx-redux> <openbios.bin>}
+BIOS=${2:?usage: $0 <pcsx-redux> <openbios.bin>}
+TIMEOUT=${TIMEOUT:-60}
+
+# name;success regex
+EXAMPLES=(
+    "frames;^BOOK-PASS frames count=[0-9]+ rate=(50|60)$"
+)
+
+fail=0
+declare -A known
+for e in "${EXAMPLES[@]}"; do known[${e%%;*}]=1; done
+for d in examples/*/; do
+    d=$(basename "$d")
+    if [ -z "${known[$d]:-}" ]; then
+        echo "UNLISTED: examples/$d is not in $0"
+        fail=1
+    fi
+done
+
+LOGS=$(mktemp -d)
+for e in "${EXAMPLES[@]}"; do
+    IFS=';' read -r name token <<< "$e"
+    exe="examples/$name/$name.ps-exe"
+    if [ ! -f "$exe" ]; then
+        echo "MISSING: $exe was not built"
+        fail=1
+        continue
+    fi
+    log="$LOGS/$name.log"
+    home="$LOGS/home-$name"
+    mkdir -p "$home"
+    HOME="$home" XDG_CONFIG_HOME="$home/.config" timeout -k 10 "$TIMEOUT" "$EMU" -no-ui -run -stdout -testmode \
+        -interpreter -bios "$BIOS" -loadexe "$exe" > "$log" 2>&1
+    rc=$?
+    line=$(sed 's/\x1b\[[0-9;]*m//g' "$log" | tr -d '\r' | grep -aE "$token" | tail -1)
+    if [ $rc -eq 0 ] && [ -n "$line" ]; then
+        echo "PASS $name: $line"
+    else
+        echo "FAIL $name: exit $rc, no success line"
+        sed 's/\x1b\[[0-9;]*m//g' "$log" | tail -40 | sed 's/^/    /'
+        fail=1
+    fi
+done
+
+[ $fail -eq 0 ] && echo "all ${#EXAMPLES[@]} example(s) passed"
+exit $fail
diff --git a/examples/book.mk b/examples/book.mk
new file mode 100644
index 0000000..f21aba4
--- /dev/null
+++ b/examples/book.mk
@@ -0,0 +1,8 @@
+# Shared by every example: the psyqo build from the nugget submodule, plus
+# the CI hook switch.
+BOOKDIR := $(dir $(abspath $(lastword $(MAKEFILE_LIST))))..
+CPPFLAGS += -I$(BOOKDIR)/ci
+ifeq ($(BOOK_CI),true)
+CPPFLAGS += -DBOOK_CI -Werror
+endif
+include $(BOOKDIR)/third_party/nugget/psyqo/psyqo.mk
diff --git a/examples/frames/Makefile b/examples/frames/Makefile
new file mode 100644
index 0000000..d4e69e9
--- /dev/null
+++ b/examples/frames/Makefile
@@ -0,0 +1,7 @@
+TARGET = frames
+TYPE = ps-exe
+
+SRCS = \
+frames.cpp \
+
+include ../book.mk
diff --git a/examples/frames/frames.cpp b/examples/frames/frames.cpp
new file mode 100644
index 0000000..ccf0b26
--- /dev/null
+++ b/examples/frames/frames.cpp
@@ -0,0 +1,57 @@
+// Counts frames and shows the count, along with the refresh rate the GPU
+// was configured for. Chapter 3, "Boot and the frame".
+
+#include "ci.hh"
+#include "psyqo/application.hh"
+#include "psyqo/font.hh"
+#include "psyqo/gpu.hh"
+#include "psyqo/scene.hh"
+
+namespace {
+
+class Frames final : public psyqo::Application {
+    void prepare() override;
+    void createScene() override;
+
+  public:
+    psyqo::Font<> m_font;
+};
+
+class FramesScene final : public psyqo::Scene {
+    void frame() override;
+};
+
+Frames frames;
+FramesScene framesScene;
+
+}  // namespace
+
+void Frames::prepare() {
+    psyqo::GPU::Configuration config;
+    config.set(psyqo::GPU::Resolution::W320)
+        .set(psyqo::GPU::VideoMode::AUTO)
+        .set(psyqo::GPU::ColorMode::C15BITS)
+        .set(psyqo::GPU::Interlace::PROGRESSIVE);
+    gpu().initialize(config);
+}
+
+void Frames::createScene() {
+    m_font.uploadSystemFont(gpu());
+    pushScene(&framesScene);
+}
+
+void FramesScene::frame() {
+    auto& gpu = frames.gpu();
+    uint32_t count = gpu.getFrameCount();
+    unsigned rate = gpu.getRefreshRate();
+
+    gpu.clear({{.r = 0, .g = 0, .b = 0x30}});
+    frames.m_font.printf(gpu, {{.x = 16, .y = 32}}, {{.r = 0xff, .g = 0xff, .b = 0xff}}, "frame %u", count);
+    frames.m_font.printf(gpu, {{.x = 16, .y = 48}}, {{.r = 0xff, .g = 0xff, .b = 0xff}}, "%u Hz, %u.%02u s", rate,
+                         count / rate, (count % rate) * 100 / rate);
+
+    // Two seconds of frames is enough to show the vblank is ticking.
+    if (count >= 2 * rate) BOOK_CI_PASS("frames count=%u rate=%u", count, rate);
+}
+
+int main() { return frames.run(); }
diff --git a/third_party/nugget b/third_party/nugget
new file mode 160000
index 0000000..4828df5
--- /dev/null
+++ b/third_party/nugget
@@ -0,0 +1 @@
+Subproject commit 4828df55035b3e6f6ae1f331eefc01fbd80f7adf