diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7fa4821..20055c8 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,12 +14,15 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
 option(COURSE_BUILD_TESTS "Build Google Test exercise targets" ON)
 option(COURSE_WARNINGS_AS_ERRORS "Treat compiler warnings as errors" OFF)
+option(COURSE_ENABLE_CONTRACTS "Enable C++26 contracts on GCC 16+" ON)
 
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 
 include(CourseOptions)
 include(CourseExercise)
 
+add_subdirectory(support)
+
 if(COURSE_BUILD_TESTS)
     include(FetchContent)
     FetchContent_Declare(
diff --git a/README.md b/README.md
index 4e2cd28..7ec30ff 100644
--- a/README.md
+++ b/README.md
@@ -5,21 +5,33 @@ A hands-on C++ course with **56 Google Test exercises** organized into **14 modu
 ## Requirements
 
 - **CMake** 3.20+
-- **C++ compiler** with C++23 support for later modules
-  - Apple Clang 15+, GCC 13+, or MSVC 19.34+ recommended
+- **C++26-capable compiler**
+  - **GCC 16+** recommended (required for `pre`/`post` contracts)
+  - Apple Clang can build most exercises but **does not support contracts yet**
 - **CLion** (recommended) or any CMake-aware IDE
 - Internet access on first configure (Google Test is fetched automatically)
 
 ## Quick Start (CLion)
 
 1. Open this folder in CLion (`File → Open…`).
-2. CLion detects `CMakeLists.txt` and configures automatically.
-3. Pick an exercise target (e.g. `01_fundamentals_hello_world`) in the run configuration dropdown.
-4. Implement the TODOs in the matching `src/*.cpp` file.
-5. Run the test target until all assertions pass.
+2. Select the **`gcc26-contracts`** CMake profile (see `CMakePresets.json`).
+3. Reload CMake when prompted.
+4. Pick an exercise target (e.g. `02_control_flow_loops`) in the run configuration dropdown.
+5. Implement the TODOs in the matching `src/*.cpp` file.
+6. Run the test target until all assertions pass.
 
 ## Quick Start (Terminal)
 
+**Recommended — GCC 16 with contracts:**
+
+```bash
+cmake --preset gcc26-contracts
+cmake --build build-gcc26
+ctest --test-dir build-gcc26 --output-on-failure
+```
+
+**Default toolchain:**
+
 ```bash
 cmake -S . -B build -DCMAKE_BUILD_TYPE=Debug
 cmake --build build
@@ -29,8 +41,8 @@ ctest --test-dir build --output-on-failure
 Run a single exercise:
 
 ```bash
-cmake --build build --target 01_fundamentals_hello_world
-./build/modules/01_fundamentals/01_fundamentals_hello_world
+cmake --build build-gcc26 --target 02_control_flow_loops
+./build-gcc26/modules/02_control_flow/02_control_flow_loops
 ```
 
 ## Project Structure
@@ -40,7 +52,10 @@ cppc/
 ├── CMakeLists.txt              # Root project + Google Test
 ├── cmake/
 │   ├── CourseExercise.cmake    # add_course_exercise() helper
-│   └── CourseOptions.cmake     # Warnings and standards
+│   ├── CourseOptions.cmake     # Warnings, standards, contracts
+│   └── toolchains/gcc-16.cmake # Optional GCC 16 toolchain file
+├── CMakePresets.json           # CLion/CMake presets (gcc26-contracts)
+├── support/                    # Shared contract violation handler
 └── modules/
     ├── 01_fundamentals/        # Types, operators, I/O
     ├── 02_control_flow/       # if, switch, loops
@@ -75,22 +90,22 @@ Each module contains:
 
 ## Course Map
 
-| Module | Topic | Exercises | C++ Standard |
-|--------|-------|-----------|--------------|
-| 01 | Fundamentals | 4 | C++17 |
-| 02 | Control flow | 4 | C++17 |
-| 03 | Functions | 4 | C++17 |
-| 04 | Arrays & strings | 4 | C++17 |
-| 05 | Pointers & references | 4 | C++17 |
-| 06 | OOP basics | 4 | C++17 |
-| 07 | STL containers | 4 | C++17 |
-| 08 | STL algorithms | 4 | C++17 |
-| 09 | C++11 | 4 | C++11 |
-| 10 | C++14 | 4 | C++14 |
-| 11 | C++17 | 4 | C++17 |
-| 12 | C++20 | 4 | C++20 |
-| 13 | C++23 | 4 | C++23 |
-| 14 | C++26 frontier | 4 | C++23+ |
+| Module | Topic | Exercises | Build standard |
+|--------|-------|-----------|----------------|
+| 01 | Fundamentals | 4 | C++26 |
+| 02 | Control flow | 4 | C++26 |
+| 03 | Functions | 4 | C++26 |
+| 04 | Arrays & strings | 4 | C++26 |
+| 05 | Pointers & references | 4 | C++26 |
+| 06 | OOP basics | 4 | C++26 |
+| 07 | STL containers | 4 | C++26 |
+| 08 | STL algorithms | 4 | C++26 |
+| 09 | C++11 features | 4 | C++26 |
+| 10 | C++14 features | 4 | C++26 |
+| 11 | C++17 features | 4 | C++26 |
+| 12 | C++20 features | 4 | C++26 |
+| 13 | C++23 features | 4 | C++26 |
+| 14 | C++26 frontier | 4 | C++26 |
 
 ## CMake Options
 
@@ -98,11 +113,38 @@ Each module contains:
 |--------|---------|-------------|
 | `COURSE_BUILD_TESTS` | ON | Build Google Test exercise targets |
 | `COURSE_WARNINGS_AS_ERRORS` | OFF | Treat warnings as errors |
+| `COURSE_ENABLE_CONTRACTS` | ON | Enable `-fcontracts` on GCC 16+ targets |
 
 Example:
 
 ```bash
-cmake -S . -B build -DCOURSE_WARNINGS_AS_ERRORS=ON
+cmake --preset gcc26-contracts -DCOURSE_WARNINGS_AS_ERRORS=ON
+```
+
+## C++26 Contracts
+
+Exercises compile as **C++26**. On **GCC 16+**, the build enables:
+
+- `-fcontracts`
+- `-fcontract-semantic=enforce`
+- A shared `handle_contract_violation` handler in `support/contract_handler.cpp`
+
+Use `#include <contracts>` and syntax like:
+
+```cpp
+auto factorial(int n) -> long long
+    pre(n >= 0)
+{
+    // ...
+}
+```
+
+**Apple Clang does not support contracts yet.** Use the `gcc26-contracts` preset in CLion or:
+
+```bash
+cmake -S . -B build-gcc26 \
+  -DCMAKE_CXX_COMPILER=/opt/homebrew/bin/g++-16 \
+  -DCOURSE_ENABLE_CONTRACTS=ON
 ```
 
 ## CLion Tips
@@ -114,6 +156,6 @@ cmake -S . -B build -DCOURSE_WARNINGS_AS_ERRORS=ON
 
 ## Notes on C++26
 
-C++26 is still in active standardization. Module 14 focuses on techniques and library directions that remain relevant—deep `constexpr`, monadic `expected`, ranges pipelines, and `std::formatter`—using C++23 as the practical baseline.
+All exercises now build with **C++26**. Module READMEs still describe the language feature each exercise teaches (C++11, C++17, etc.), but the toolchain baseline is unified at C++26 for a consistent modern environment.
 
 Happy learning!
diff --git a/cmake/CourseExercise.cmake b/cmake/CourseExercise.cmake
index f7022d8..97bfb8a 100644
--- a/cmake/CourseExercise.cmake
+++ b/cmake/CourseExercise.cmake
@@ -21,7 +21,7 @@ function(add_course_exercise)
     endif()
 
     if(NOT EXERCISE_STANDARD)
-        set(EXERCISE_STANDARD 23)
+        set(EXERCISE_STANDARD 26)
     endif()
 
     set(target_name "${EXERCISE_MODULE}_${EXERCISE_NAME}")
@@ -33,6 +33,11 @@ function(add_course_exercise)
             "${CMAKE_CURRENT_SOURCE_DIR}/include"
     )
     course_set_cxx_standard(${target_name} ${EXERCISE_STANDARD})
+
+    if(EXERCISE_STANDARD GREATER_EQUAL 26)
+        course_enable_contracts(${target_name})
+    endif()
+
     course_apply_warnings(${target_name})
 
     if(COURSE_BUILD_TESTS)
diff --git a/cmake/CourseOptions.cmake b/cmake/CourseOptions.cmake
index f7df5cc..b13be6e 100644
--- a/cmake/CourseOptions.cmake
+++ b/cmake/CourseOptions.cmake
@@ -23,3 +23,22 @@ endfunction()
 function(course_set_cxx_standard target_name standard)
     target_compile_features(${target_name} PRIVATE cxx_std_${standard})
 endfunction()
+
+function(course_enable_contracts target_name)
+    if(NOT COURSE_ENABLE_CONTRACTS)
+        return()
+    endif()
+
+    if(NOT (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER_EQUAL 16))
+        return()
+    endif()
+
+    target_compile_options(
+        ${target_name}
+        PRIVATE
+            -fcontracts
+            -fcontract-evaluation-semantic=enforce
+    )
+    target_link_options(${target_name} PRIVATE -fcontracts)
+    target_link_libraries(${target_name} PRIVATE course_contract_support)
+endfunction()
diff --git a/modules/01_fundamentals/CMakeLists.txt b/modules/01_fundamentals/CMakeLists.txt
index 8969e1b..1c2266b 100644
--- a/modules/01_fundamentals/CMakeLists.txt
+++ b/modules/01_fundamentals/CMakeLists.txt
@@ -1,7 +1,7 @@
 add_course_exercise(
     NAME hello_world
     MODULE 01_fundamentals
-    STANDARD 17
+    STANDARD 26
     SOURCES
         src/hello_world.cpp
         test/hello_world_test.cpp
@@ -10,7 +10,7 @@ add_course_exercise(
 add_course_exercise(
     NAME variables_and_types
     MODULE 01_fundamentals
-    STANDARD 17
+    STANDARD 26
     SOURCES
         src/variables_and_types.cpp
         test/variables_and_types_test.cpp
@@ -19,7 +19,7 @@ add_course_exercise(
 add_course_exercise(
     NAME operators
     MODULE 01_fundamentals
-    STANDARD 17
+    STANDARD 26
     SOURCES
         src/operators.cpp
         test/operators_test.cpp
@@ -28,7 +28,7 @@ add_course_exercise(
 add_course_exercise(
     NAME basic_io
     MODULE 01_fundamentals
-    STANDARD 17
+    STANDARD 26
     SOURCES
         src/basic_io.cpp
         test/basic_io_test.cpp
diff --git a/modules/02_control_flow/CMakeLists.txt b/modules/02_control_flow/CMakeLists.txt
index f049c1c..b84f0e0 100644
--- a/modules/02_control_flow/CMakeLists.txt
+++ b/modules/02_control_flow/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME conditionals MODULE 02_control_flow STANDARD 17
+add_course_exercise(NAME conditionals MODULE 02_control_flow STANDARD 26
     SOURCES src/conditionals.cpp test/conditionals_test.cpp)
-add_course_exercise(NAME switch_statements MODULE 02_control_flow STANDARD 17
+add_course_exercise(NAME switch_statements MODULE 02_control_flow STANDARD 26
     SOURCES src/switch_statements.cpp test/switch_statements_test.cpp)
-add_course_exercise(NAME loops MODULE 02_control_flow STANDARD 17
+add_course_exercise(NAME loops MODULE 02_control_flow STANDARD 26
     SOURCES src/loops.cpp test/loops_test.cpp)
-add_course_exercise(NAME break_continue MODULE 02_control_flow STANDARD 17
+add_course_exercise(NAME break_continue MODULE 02_control_flow STANDARD 26
     SOURCES src/break_continue.cpp test/break_continue_test.cpp)
diff --git a/modules/03_functions/CMakeLists.txt b/modules/03_functions/CMakeLists.txt
index 52df6ec..752bb90 100644
--- a/modules/03_functions/CMakeLists.txt
+++ b/modules/03_functions/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME function_basics MODULE 03_functions STANDARD 17
+add_course_exercise(NAME function_basics MODULE 03_functions STANDARD 26
     SOURCES src/function_basics.cpp test/function_basics_test.cpp)
-add_course_exercise(NAME overloading MODULE 03_functions STANDARD 17
+add_course_exercise(NAME overloading MODULE 03_functions STANDARD 26
     SOURCES src/overloading.cpp test/overloading_test.cpp)
-add_course_exercise(NAME default_parameters MODULE 03_functions STANDARD 17
+add_course_exercise(NAME default_parameters MODULE 03_functions STANDARD 26
     SOURCES src/default_parameters.cpp test/default_parameters_test.cpp)
-add_course_exercise(NAME recursion MODULE 03_functions STANDARD 17
+add_course_exercise(NAME recursion MODULE 03_functions STANDARD 26
     SOURCES src/recursion.cpp test/recursion_test.cpp)
diff --git a/modules/04_arrays_and_strings/CMakeLists.txt b/modules/04_arrays_and_strings/CMakeLists.txt
index 606cf50..11670e3 100644
--- a/modules/04_arrays_and_strings/CMakeLists.txt
+++ b/modules/04_arrays_and_strings/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME c_arrays MODULE 04_arrays_and_strings STANDARD 17
+add_course_exercise(NAME c_arrays MODULE 04_arrays_and_strings STANDARD 26
     SOURCES src/c_arrays.cpp test/c_arrays_test.cpp)
-add_course_exercise(NAME std_string MODULE 04_arrays_and_strings STANDARD 17
+add_course_exercise(NAME std_string MODULE 04_arrays_and_strings STANDARD 26
     SOURCES src/std_string.cpp test/std_string_test.cpp)
-add_course_exercise(NAME std_vector MODULE 04_arrays_and_strings STANDARD 17
+add_course_exercise(NAME std_vector MODULE 04_arrays_and_strings STANDARD 26
     SOURCES src/std_vector.cpp test/std_vector_test.cpp)
-add_course_exercise(NAME multidimensional MODULE 04_arrays_and_strings STANDARD 17
+add_course_exercise(NAME multidimensional MODULE 04_arrays_and_strings STANDARD 26
     SOURCES src/multidimensional.cpp test/multidimensional_test.cpp)
diff --git a/modules/05_pointers_and_references/CMakeLists.txt b/modules/05_pointers_and_references/CMakeLists.txt
index 8acef1d..e22fd88 100644
--- a/modules/05_pointers_and_references/CMakeLists.txt
+++ b/modules/05_pointers_and_references/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME pointer_basics MODULE 05_pointers_and_references STANDARD 17
+add_course_exercise(NAME pointer_basics MODULE 05_pointers_and_references STANDARD 26
     SOURCES src/pointer_basics.cpp test/pointer_basics_test.cpp)
-add_course_exercise(NAME references MODULE 05_pointers_and_references STANDARD 17
+add_course_exercise(NAME references MODULE 05_pointers_and_references STANDARD 26
     SOURCES src/references.cpp test/references_test.cpp)
-add_course_exercise(NAME pointer_arithmetic MODULE 05_pointers_and_references STANDARD 17
+add_course_exercise(NAME pointer_arithmetic MODULE 05_pointers_and_references STANDARD 26
     SOURCES src/pointer_arithmetic.cpp test/pointer_arithmetic_test.cpp)
-add_course_exercise(NAME dynamic_memory MODULE 05_pointers_and_references STANDARD 17
+add_course_exercise(NAME dynamic_memory MODULE 05_pointers_and_references STANDARD 26
     SOURCES src/dynamic_memory.cpp test/dynamic_memory_test.cpp)
diff --git a/modules/06_oop_basics/CMakeLists.txt b/modules/06_oop_basics/CMakeLists.txt
index e91bdb8..66987fd 100644
--- a/modules/06_oop_basics/CMakeLists.txt
+++ b/modules/06_oop_basics/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME classes_and_objects MODULE 06_oop_basics STANDARD 17
+add_course_exercise(NAME classes_and_objects MODULE 06_oop_basics STANDARD 26
     SOURCES src/classes_and_objects.cpp test/classes_and_objects_test.cpp)
-add_course_exercise(NAME constructors MODULE 06_oop_basics STANDARD 17
+add_course_exercise(NAME constructors MODULE 06_oop_basics STANDARD 26
     SOURCES src/constructors.cpp test/constructors_test.cpp)
-add_course_exercise(NAME inheritance MODULE 06_oop_basics STANDARD 17
+add_course_exercise(NAME inheritance MODULE 06_oop_basics STANDARD 26
     SOURCES src/inheritance.cpp test/inheritance_test.cpp)
-add_course_exercise(NAME polymorphism MODULE 06_oop_basics STANDARD 17
+add_course_exercise(NAME polymorphism MODULE 06_oop_basics STANDARD 26
     SOURCES src/polymorphism.cpp src/inheritance.cpp test/polymorphism_test.cpp)
diff --git a/modules/07_stl_containers/CMakeLists.txt b/modules/07_stl_containers/CMakeLists.txt
index 7928d4d..71d4d70 100644
--- a/modules/07_stl_containers/CMakeLists.txt
+++ b/modules/07_stl_containers/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME sequential_containers MODULE 07_stl_containers STANDARD 17
+add_course_exercise(NAME sequential_containers MODULE 07_stl_containers STANDARD 26
     SOURCES src/sequential_containers.cpp test/sequential_containers_test.cpp)
-add_course_exercise(NAME associative_containers MODULE 07_stl_containers STANDARD 17
+add_course_exercise(NAME associative_containers MODULE 07_stl_containers STANDARD 26
     SOURCES src/associative_containers.cpp test/associative_containers_test.cpp)
-add_course_exercise(NAME unordered_containers MODULE 07_stl_containers STANDARD 17
+add_course_exercise(NAME unordered_containers MODULE 07_stl_containers STANDARD 26
     SOURCES src/unordered_containers.cpp test/unordered_containers_test.cpp)
-add_course_exercise(NAME container_adapters MODULE 07_stl_containers STANDARD 17
+add_course_exercise(NAME container_adapters MODULE 07_stl_containers STANDARD 26
     SOURCES src/container_adapters.cpp test/container_adapters_test.cpp)
diff --git a/modules/08_stl_algorithms/CMakeLists.txt b/modules/08_stl_algorithms/CMakeLists.txt
index c3cab2f..f877a18 100644
--- a/modules/08_stl_algorithms/CMakeLists.txt
+++ b/modules/08_stl_algorithms/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME sort_and_find MODULE 08_stl_algorithms STANDARD 17
+add_course_exercise(NAME sort_and_find MODULE 08_stl_algorithms STANDARD 26
     SOURCES src/sort_and_find.cpp test/sort_and_find_test.cpp)
-add_course_exercise(NAME transform_reduce MODULE 08_stl_algorithms STANDARD 17
+add_course_exercise(NAME transform_reduce MODULE 08_stl_algorithms STANDARD 26
     SOURCES src/transform_reduce.cpp test/transform_reduce_test.cpp)
-add_course_exercise(NAME iterators MODULE 08_stl_algorithms STANDARD 17
+add_course_exercise(NAME iterators MODULE 08_stl_algorithms STANDARD 26
     SOURCES src/iterators.cpp test/iterators_test.cpp)
-add_course_exercise(NAME algorithm_lambdas MODULE 08_stl_algorithms STANDARD 17
+add_course_exercise(NAME algorithm_lambdas MODULE 08_stl_algorithms STANDARD 26
     SOURCES src/algorithm_lambdas.cpp test/algorithm_lambdas_test.cpp)
diff --git a/modules/09_cpp11/CMakeLists.txt b/modules/09_cpp11/CMakeLists.txt
index 0df8cb0..af1d24b 100644
--- a/modules/09_cpp11/CMakeLists.txt
+++ b/modules/09_cpp11/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME auto_and_range_for MODULE 09_cpp11 STANDARD 11
+add_course_exercise(NAME auto_and_range_for MODULE 09_cpp11 STANDARD 26
     SOURCES src/auto_and_range_for.cpp test/auto_and_range_for_test.cpp)
-add_course_exercise(NAME smart_pointers MODULE 09_cpp11 STANDARD 11
+add_course_exercise(NAME smart_pointers MODULE 09_cpp11 STANDARD 26
     SOURCES src/smart_pointers.cpp test/smart_pointers_test.cpp)
-add_course_exercise(NAME move_semantics MODULE 09_cpp11 STANDARD 11
+add_course_exercise(NAME move_semantics MODULE 09_cpp11 STANDARD 26
     SOURCES src/move_semantics.cpp test/move_semantics_test.cpp)
-add_course_exercise(NAME constexpr_nullptr MODULE 09_cpp11 STANDARD 11
+add_course_exercise(NAME constexpr_nullptr MODULE 09_cpp11 STANDARD 26
     SOURCES src/constexpr_nullptr.cpp test/constexpr_nullptr_test.cpp)
diff --git a/modules/10_cpp14/CMakeLists.txt b/modules/10_cpp14/CMakeLists.txt
index 5191e0c..3f466f7 100644
--- a/modules/10_cpp14/CMakeLists.txt
+++ b/modules/10_cpp14/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME generic_lambdas MODULE 10_cpp14 STANDARD 14
+add_course_exercise(NAME generic_lambdas MODULE 10_cpp14 STANDARD 26
     SOURCES src/generic_lambdas.cpp test/generic_lambdas_test.cpp)
-add_course_exercise(NAME auto_return MODULE 10_cpp14 STANDARD 14
+add_course_exercise(NAME auto_return MODULE 10_cpp14 STANDARD 26
     SOURCES src/auto_return.cpp test/auto_return_test.cpp)
-add_course_exercise(NAME make_unique MODULE 10_cpp14 STANDARD 14
+add_course_exercise(NAME make_unique MODULE 10_cpp14 STANDARD 26
     SOURCES src/make_unique.cpp test/make_unique_test.cpp)
-add_course_exercise(NAME digit_separators MODULE 10_cpp14 STANDARD 14
+add_course_exercise(NAME digit_separators MODULE 10_cpp14 STANDARD 26
     SOURCES src/digit_separators.cpp test/digit_separators_test.cpp)
diff --git a/modules/11_cpp17/CMakeLists.txt b/modules/11_cpp17/CMakeLists.txt
index 90cabd1..38c9995 100644
--- a/modules/11_cpp17/CMakeLists.txt
+++ b/modules/11_cpp17/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME structured_bindings MODULE 11_cpp17 STANDARD 17
+add_course_exercise(NAME structured_bindings MODULE 11_cpp17 STANDARD 26
     SOURCES src/structured_bindings.cpp test/structured_bindings_test.cpp)
-add_course_exercise(NAME optional MODULE 11_cpp17 STANDARD 17
+add_course_exercise(NAME optional MODULE 11_cpp17 STANDARD 26
     SOURCES src/optional.cpp test/optional_test.cpp)
-add_course_exercise(NAME variant MODULE 11_cpp17 STANDARD 17
+add_course_exercise(NAME variant MODULE 11_cpp17 STANDARD 26
     SOURCES src/variant.cpp test/variant_test.cpp)
-add_course_exercise(NAME if_constexpr MODULE 11_cpp17 STANDARD 17
+add_course_exercise(NAME if_constexpr MODULE 11_cpp17 STANDARD 26
     SOURCES src/if_constexpr.cpp test/if_constexpr_test.cpp)
diff --git a/modules/12_cpp20/CMakeLists.txt b/modules/12_cpp20/CMakeLists.txt
index 8e09365..0bd2336 100644
--- a/modules/12_cpp20/CMakeLists.txt
+++ b/modules/12_cpp20/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME concepts MODULE 12_cpp20 STANDARD 20
+add_course_exercise(NAME concepts MODULE 12_cpp20 STANDARD 26
     SOURCES src/concepts.cpp test/concepts_test.cpp)
-add_course_exercise(NAME ranges MODULE 12_cpp20 STANDARD 20
+add_course_exercise(NAME ranges MODULE 12_cpp20 STANDARD 26
     SOURCES src/ranges.cpp test/ranges_test.cpp)
-add_course_exercise(NAME spaceship_operator MODULE 12_cpp20 STANDARD 20
+add_course_exercise(NAME spaceship_operator MODULE 12_cpp20 STANDARD 26
     SOURCES src/spaceship_operator.cpp test/spaceship_operator_test.cpp)
-add_course_exercise(NAME span MODULE 12_cpp20 STANDARD 20
+add_course_exercise(NAME span MODULE 12_cpp20 STANDARD 26
     SOURCES src/span.cpp test/span_test.cpp)
diff --git a/modules/13_cpp23/CMakeLists.txt b/modules/13_cpp23/CMakeLists.txt
index 58ed470..535bbf6 100644
--- a/modules/13_cpp23/CMakeLists.txt
+++ b/modules/13_cpp23/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME expected MODULE 13_cpp23 STANDARD 23
+add_course_exercise(NAME expected MODULE 13_cpp23 STANDARD 26
     SOURCES src/expected.cpp test/expected_test.cpp)
-add_course_exercise(NAME print_and_format MODULE 13_cpp23 STANDARD 23
+add_course_exercise(NAME print_and_format MODULE 13_cpp23 STANDARD 26
     SOURCES src/print_and_format.cpp test/print_and_format_test.cpp)
-add_course_exercise(NAME mdspan MODULE 13_cpp23 STANDARD 23
+add_course_exercise(NAME mdspan MODULE 13_cpp23 STANDARD 26
     SOURCES src/mdspan.cpp test/mdspan_test.cpp)
-add_course_exercise(NAME ranges_zip MODULE 13_cpp23 STANDARD 23
+add_course_exercise(NAME ranges_zip MODULE 13_cpp23 STANDARD 26
     SOURCES src/ranges_zip.cpp test/ranges_zip_test.cpp)
diff --git a/modules/14_cpp26/CMakeLists.txt b/modules/14_cpp26/CMakeLists.txt
index dd2f935..0567c85 100644
--- a/modules/14_cpp26/CMakeLists.txt
+++ b/modules/14_cpp26/CMakeLists.txt
@@ -1,8 +1,8 @@
-add_course_exercise(NAME constexpr_frontier MODULE 14_cpp26 STANDARD 23
+add_course_exercise(NAME constexpr_frontier MODULE 14_cpp26 STANDARD 26
     SOURCES src/constexpr_frontier.cpp test/constexpr_frontier_test.cpp)
-add_course_exercise(NAME monadic_expected MODULE 14_cpp26 STANDARD 23
+add_course_exercise(NAME monadic_expected MODULE 14_cpp26 STANDARD 26
     SOURCES src/monadic_expected.cpp test/monadic_expected_test.cpp)
-add_course_exercise(NAME pipeline_ranges MODULE 14_cpp26 STANDARD 23
+add_course_exercise(NAME pipeline_ranges MODULE 14_cpp26 STANDARD 26
     SOURCES src/pipeline_ranges.cpp test/pipeline_ranges_test.cpp)
-add_course_exercise(NAME custom_formatter MODULE 14_cpp26 STANDARD 23
+add_course_exercise(NAME custom_formatter MODULE 14_cpp26 STANDARD 26
     SOURCES src/custom_formatter.cpp test/custom_formatter_test.cpp)