mkdir gdextension_example && cd gdextension_example
git init

Directory layout:

Build with `scons platform=<platform>` (omit the platform to target the current one; default build is **debug**). The official `SConstruct` is a downloadable file from the C++ tutorial rather than hand-rolled here — follow godot-cpp's build docs. SCons is the official path; godot-cpp also supports CMake.

> **Godot 4.7+:** Upstream's reference GDExtension interface files (e.g. `gdextension_interface.h`) now live in the godot-headers repository instead of godot-cpp ([GH-115401](https://github.com/godotengine/godot/pull/115401)). godot-cpp consumes them from there, so the submodule workflow above is unchanged — this only matters if you vendor the raw interface headers directly (e.g. for a custom language binding).

---

#pragma once
#include <godot_cpp/classes/sprite2d.hpp>

namespace godot {
class GDExample : public Sprite2D {
    GDCLASS(GDExample, Sprite2D)
private:
    double time_passed = 0.0;
    double amplitude = 10.0;
    double speed = 1.0;
protected:
    static void _bind_methods();
public:
    void _process(double delta) override;
    void set_amplitude(double p_amplitude);
    double get_amplitude() const;
    void set_speed(double p_speed);
    double get_speed() const;
};
}

void GDExample::_bind_methods() {
    ClassDB::bind_method(D_METHOD("get_amplitude"), &GDExample::get_amplitude);
    ClassDB::bind_method(D_METHOD("set_amplitude", "p_amplitude"), &GDExample::set_amplitude);
    ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "amplitude"), "set_amplitude", "get_amplitude");

    ClassDB::bind_method(D_METHOD("get_speed"), &GDExample::get_speed);
    ClassDB::bind_method(D_METHOD("set_speed", "p_speed"), &GDExample::set_speed);
    ADD_PROPERTY(PropertyInfo(Variant::FLOAT, "speed", PROPERTY_HINT_RANGE, "0,20,0.01"),
                 "set_speed", "get_speed");

    ADD_SIGNAL(MethodInfo("position_changed",
               PropertyInfo(Variant::OBJECT, "node"),
               PropertyInfo(Variant::VECTOR2, "new_pos")));
}

void initialize_example_module(ModuleInitializationLevel p_level) {
    if (p_level != MODULE_INITIALIZATION_LEVEL_SCENE) return;
    GDREGISTER_CLASS(GDExample);
}
void uninitialize_example_module(ModuleInitializationLevel p_level) {
    if (p_level != MODULE_INITIALIZATION_LEVEL_SCENE) return;
}
extern "C" {
GDExtensionBool GDE_EXPORT example_library_init(
    GDExtensionInterfaceGetProcAddress p_get_proc_address,
    const GDExtensionClassLibraryPtr p_library,
    GDExtensionInitialization *r_initialization) {
    godot::GDExtensionBinding::InitObject init_obj(p_get_proc_address, p_library, r_initialization);
    init_obj.register_initializer(initialize_example_module);
    init_obj.register_terminator(uninitialize_example_module);
    init_obj.set_minimum_library_initialization_level(MODULE_INITIALIZATION_LEVEL_SCENE);
    return init_obj.init();
}
}

[configuration]
entry_symbol = "example_library_init"
compatibility_minimum = "4.3"
reloadable = true

[libraries]
macos.debug = "res://bin/libgdexample.macos.template_debug.dylib"
macos.release = "res://bin/libgdexample.macos.template_release.dylib"
windows.debug.x86_64 = "res://bin/gdexample.windows.template_debug.x86_64.dll"
windows.release.x86_64 = "res://bin/gdexample.windows.template_release.x86_64.dll"
linux.debug.x86_64 = "res://bin/libgdexample.linux.template_debug.x86_64.so"
linux.release.x86_64 = "res://bin/libgdexample.linux.template_release.x86_64.so"

extends Node

func _ready():
    var node := GDExample.new()
    node.speed = 2.0
    node.position_changed.connect(_on_position_changed)
    add_child(node)

func _on_position_changed(node, new_pos):
    print("%s is now at %s" % [node.get_class(), new_pos])

using Godot;

public partial class Demo : Node
{
    public override void _Ready()
    {
        var node = new GDExample(); // The native class is available like any Godot type.
        node.Set("speed", 2.0);
        node.Connect("position_changed", Callable.From<Node, Vector2>(OnPositionChanged));
        AddChild(node);
    }

    private void OnPositionChanged(Node node, Vector2 newPos)
        => GD.Print($"{node.GetClass()} is now at {newPos}");
}