diff --git a/src/camera.hpp b/src/camera.hpp
index 4b4f72f..f348d25 100644
--- a/src/camera.hpp
+++ b/src/camera.hpp
@@ -4,10 +4,9 @@
 #include "transformation.hpp"
 #include "scene.hpp"
 
-class Camera :
-  public Transformation
+struct Camera :
+  Transformation
 {
-public:
   inline Camera(const Scene &scene) : _scene(scene) {}
 
   inline void draw() const;
diff --git a/src/material.hpp b/src/material.hpp
index 8f72063..905e2e1 100644
--- a/src/material.hpp
+++ b/src/material.hpp
@@ -3,9 +3,8 @@
 
 #include "texture.hpp"
 
-class Material
+struct Material
 {
-public:
   inline void use() const;
 
   const Texture *texture;
diff --git a/src/mtllib.hpp b/src/mtllib.hpp
index ab92ecb..8eb12d5 100644
--- a/src/mtllib.hpp
+++ b/src/mtllib.hpp
@@ -7,12 +7,11 @@
 #include <string>
 #include <map>
 
-class Mtllib:
-  public Resource
+struct Mtllib:
+  Resource
 {
   RESOURCE(Mtllib)
 
-public:
   const Material *operator[](const std::string &name) const;
 
 private:
diff --git a/src/object.hpp b/src/object.hpp
index 0696d46..ce72b7b 100644
--- a/src/object.hpp
+++ b/src/object.hpp
@@ -6,10 +6,9 @@
 
 #include <glm/glm.hpp>
 
-class Object :
-  public Transformation
+struct Object :
+  Transformation
 {
-public:
   Object(const Model &model) : _model(model) {};
   void draw(const glm::mat4 &mvp) const;
 
diff --git a/src/program.hpp b/src/program.hpp
index c88c034..e523d67 100644
--- a/src/program.hpp
+++ b/src/program.hpp
@@ -6,12 +6,11 @@
 
 #include <string>
 
-class Program:
-  public Resource
+struct Program:
+  Resource
 {
   RESOURCE(Program)
 
-public:
   void use() const;
   GLuint get_uniform_location(const GLchar *name) const;
 
diff --git a/src/resource.hpp b/src/resource.hpp
index 6be04c7..c1e1e9a 100644
--- a/src/resource.hpp
+++ b/src/resource.hpp
@@ -3,17 +3,17 @@
 
 #include "store.hpp"
 
-class Resource
+struct Resource
 {
-  friend class Store;
+private:
+  friend struct Store;
 
   __attribute__((unused)) // Used by friend class Store
   unsigned long _ref_count = 0;
 };
 
 #define RESOURCE(T) \
-private: \
-  friend class ::Store; \
+  friend struct ::Store; \
   T(Store &store, const std::string &name); \
   static const std::string filename(const std::string &name);
 
diff --git a/src/scene.hpp b/src/scene.hpp
index f534d5a..629e1f5 100644
--- a/src/scene.hpp
+++ b/src/scene.hpp
@@ -7,9 +7,8 @@
 
 #include <glm/glm.hpp>
 
-class Scene
+struct Scene
 {
-public:
   inline Scene &operator <<(Object *object);
 
   inline void draw(const glm::mat4 &mvp) const;
diff --git a/src/shader.hpp b/src/shader.hpp
index 1784d47..806d77d 100644
--- a/src/shader.hpp
+++ b/src/shader.hpp
@@ -3,9 +3,8 @@
 
 #include "gl.hpp"
 
-class Shader
+struct Shader
 {
-public:
   Shader(GLenum type, const char *filename);
   inline GLuint id() const { return _id; };
 
diff --git a/src/store.hpp b/src/store.hpp
index 1fa6a91..ff60c2b 100644
--- a/src/store.hpp
+++ b/src/store.hpp
@@ -5,11 +5,10 @@
 #include <string>
 #include <map>
 
-class Resource;
+struct Resource;
 
-class Store
+struct Store
 {
-public:
   template <class T>
   const T *load(const std::string &name);
 
diff --git a/src/texture.hpp b/src/texture.hpp
index c138b71..d7e8cbb 100644
--- a/src/texture.hpp
+++ b/src/texture.hpp
@@ -6,13 +6,11 @@
 
 #include <string>
 
-class Texture:
-  public Resource
+struct Texture:
+  Resource
 {
   RESOURCE(Texture)
 
-public:
-
   void use() const;
 
 private:
diff --git a/src/transformation.hpp b/src/transformation.hpp
index 680cb9e..ba352e7 100644
--- a/src/transformation.hpp
+++ b/src/transformation.hpp
@@ -3,9 +3,8 @@
 
 #include <glm/glm.hpp>
 
-class Transformation
+struct Transformation
 {
-public:
   glm::mat4 transformation() const;
 
   glm::mat4 base;