diff --git a/chapters/CMakeLists.txt b/chapters/CMakeLists.txt
index 5c13caf..73f2f7f 100644
--- a/chapters/CMakeLists.txt
+++ b/chapters/CMakeLists.txt
@@ -1 +1,2 @@
+add_subdirectory(interface)
 add_subdirectory(chapter_02)
diff --git a/chapters/chapter_02/CMakeLists.txt b/chapters/chapter_02/CMakeLists.txt
index 51d62aa..7be36fd 100644
--- a/chapters/chapter_02/CMakeLists.txt
+++ b/chapters/chapter_02/CMakeLists.txt
@@ -1,4 +1,8 @@
 add_library(chapter_02 src/initlist.cpp src/null.cpp src/constexp.cpp
                        src/ifswitch.cpp)
 
+target_compile_features(chapter_02 PUBLIC cxx_std_20)
+
 target_include_directories(chapter_02 PUBLIC include)
+
+target_link_libraries(chapter_02 PUBLIC chapter_interface)
diff --git a/chapters/chapter_02/include/constexp.h b/chapters/chapter_02/include/constexp.h
index 362b4ff..1e9d6ef 100644
--- a/chapters/chapter_02/include/constexp.h
+++ b/chapters/chapter_02/include/constexp.h
@@ -1,5 +1,8 @@
 #pragma once
 
-namespace constexp {
-void test();
+#include "chapter_interface.h"
+
+class ConstExpTest : public ChapterTest {
+public:
+  virtual void test() override;
 };
diff --git a/chapters/chapter_02/include/ifswitch.h b/chapters/chapter_02/include/ifswitch.h
index 405756b..dfd4a6d 100644
--- a/chapters/chapter_02/include/ifswitch.h
+++ b/chapters/chapter_02/include/ifswitch.h
@@ -1,7 +1,8 @@
 #pragma once
 
-namespace ifswitch {
-
-void test();
+#include "chapter_interface.h"
 
+class IfswitchTest : public ChapterTest {
+public:
+  virtual void test() override;
 };
diff --git a/chapters/chapter_02/include/initlist.h b/chapters/chapter_02/include/initlist.h
index aa02a20..b92f891 100644
--- a/chapters/chapter_02/include/initlist.h
+++ b/chapters/chapter_02/include/initlist.h
@@ -1,5 +1,8 @@
 #pragma once
 
-namespace initlist {
-void test();
+#include "chapter_interface.h"
+
+class InitListTest : public ChapterTest {
+public:
+  virtual void test() override;
 };
diff --git a/chapters/chapter_02/include/null.h b/chapters/chapter_02/include/null.h
index e8434f7..f72f834 100644
--- a/chapters/chapter_02/include/null.h
+++ b/chapters/chapter_02/include/null.h
@@ -1,5 +1,8 @@
 #pragma once
 
-namespace null {
-void test();
+#include "chapter_interface.h"
+
+class NullTest : public ChapterTest {
+public:
+  virtual void test() override;
 };
diff --git a/chapters/chapter_02/src/constexp.cpp b/chapters/chapter_02/src/constexp.cpp
index f0a5d73..3d3479a 100644
--- a/chapters/chapter_02/src/constexp.cpp
+++ b/chapters/chapter_02/src/constexp.cpp
@@ -9,7 +9,7 @@ constexpr unsigned int fibonacci(const unsigned int n) {
   return fibonacci(n - 2) + fibonacci(n - 1);
 }
 
-void constexp::test() {
+void ConstExpTest::test() {
   std::cout << "Fibonacci(10): ";
   for (const unsigned int n : {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}) {
     std::cout << fibonacci(n) << " ";
diff --git a/chapters/chapter_02/src/ifswitch.cpp b/chapters/chapter_02/src/ifswitch.cpp
index 995ff1a..54ce430 100644
--- a/chapters/chapter_02/src/ifswitch.cpp
+++ b/chapters/chapter_02/src/ifswitch.cpp
@@ -5,7 +5,7 @@
 
 #include "ifswitch.h"
 
-void ifswitch::test() {
+void IfswitchTest::test() {
   std::vector<uint32_t> vec = {1, 2, 3, 4};
 
   if (auto it = std::find(vec.begin(), vec.end(), 23); it != vec.end()) {
diff --git a/chapters/chapter_02/src/initlist.cpp b/chapters/chapter_02/src/initlist.cpp
index 01c0c02..3eb17c8 100644
--- a/chapters/chapter_02/src/initlist.cpp
+++ b/chapters/chapter_02/src/initlist.cpp
@@ -10,7 +10,7 @@ public:
   InitList(std::initializer_list<unsigned int> list) : _list(list) {}
 };
 
-void initlist::test() {
+void InitListTest::test() {
 
   InitList initList{1, 2, 3, 4, 5};
 
diff --git a/chapters/chapter_02/src/null.cpp b/chapters/chapter_02/src/null.cpp
index 066e95f..dc71324 100644
--- a/chapters/chapter_02/src/null.cpp
+++ b/chapters/chapter_02/src/null.cpp
@@ -7,7 +7,7 @@ void call_test(char *) { std::cout << "call_test(char *) called" << std::endl; }
 
 void call_test(int) { std::cout << "call_test(int) called" << std::endl; }
 
-void null::test() {
+void NullTest::test() {
   if (std::is_same<decltype(NULL), decltype(0)>::value) {
     std::cout << "NULL == 0" << std::endl;
   }
diff --git a/chapters/interface/CMakeLists.txt b/chapters/interface/CMakeLists.txt
new file mode 100644
index 0000000..c455881
--- /dev/null
+++ b/chapters/interface/CMakeLists.txt
@@ -0,0 +1,3 @@
+add_library(chapter_interface INTERFACE)
+target_compile_features(chapter_interface INTERFACE cxx_std_20)
+target_include_directories(chapter_interface INTERFACE include)
diff --git a/chapters/interface/include/chapter_interface.h b/chapters/interface/include/chapter_interface.h
new file mode 100644
index 0000000..d45b9ad
--- /dev/null
+++ b/chapters/interface/include/chapter_interface.h
@@ -0,0 +1,7 @@
+#pragma once
+
+class ChapterTest {
+public:
+  virtual ~ChapterTest() = default;
+  virtual void test() = 0;
+};
diff --git a/src/main.cpp b/src/main.cpp
index 8dd124e..0d3f429 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,5 +1,8 @@
 #include <cstdlib>
 #include <iostream>
+#include <memory>
+#include <string>
+#include <vector>
 
 #include "constexp.h"
 #include "ifswitch.h"
@@ -12,20 +15,18 @@ int main(int argc, char **argv) {
   std::cout << "Running " << PROJECT_NAME << ", version " << VERSION << "\n"
             << std::endl;
 
-  std::cout << "Null test:" << std::endl;
-  null::test();
+  std::vector<std::tuple<std::string, std::unique_ptr<ChapterTest>>>
+      chapterTests;
+  chapterTests.emplace_back("Null test", std::make_unique<NullTest>());
+  chapterTests.emplace_back("If/Switch test", std::make_unique<IfswitchTest>());
+  chapterTests.emplace_back("Constexpr test", std::make_unique<ConstExpTest>());
+  chapterTests.emplace_back("Initializer list test",
+                            std::make_unique<InitListTest>());
 
-  std::cout << "\n"
-            << "Constexpr test:" << std::endl;
-  constexp::test();
-
-  std::cout << "\n"
-            << "Ifswitch test:" << std::endl;
-  ifswitch::test();
-
-  std::cout << "\n"
-            << "Initializer list test:" << std::endl;
-  initlist::test();
+  for (auto &[name, test] : chapterTests) {
+    std::cout << "\n" << name << std::endl;
+    test->test();
+  }
 
   std::cout << "\nExiting" << std::endl;