diff --git a/.gitignore b/.gitignore
index 378eac2..1b2211d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1 @@
-build
+build*
diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..d827524
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,26 @@
+cmake_minimum_required (VERSION 3.1)
+list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/cmake")
+include(addPacsExecutable)
+
+project (PACS_EXAMPLES)
+
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+# disable clang-tidy to avoid compilation issues
+# set(CMAKE_CXX_CLANG_TIDY "clang-tidy;-checks=*")
+
+
+set(CMAKE_THREAD_PREFER_PTHREAD TRUE)
+set(THREADS_PREFER_PTHREAD_FLAG TRUE)
+find_package(Threads REQUIRED)
+
+if (MSVC)
+    # warning level 4 and all warnings as errors
+    add_compile_options(/W4 /WX)
+else()
+    # lots of warnings and all warnings as errors
+    add_compile_options(-Wall -Wextra -pedantic -Werror)
+endif()
+
+add_subdirectory(code_examples)
+add_subdirectory(Laboratory-3)
diff --git a/Laboratory-3/CMakeLists.txt b/Laboratory-3/CMakeLists.txt
new file mode 100644
index 0000000..a5f452d
--- /dev/null
+++ b/Laboratory-3/CMakeLists.txt
@@ -0,0 +1,2 @@
+ADD_PACS_EXECUTABLE(TARGET pi_taylor_sequential SOURCES pi_taylor_sequential.cc)
+ADD_PACS_EXECUTABLE(TARGET pi_taylor_parallel SOURCES pi_taylor_parallel.cc)
diff --git a/Laboratory-3/pi_taylor_parallel.cc b/Laboratory-3/pi_taylor_parallel.cc
new file mode 100644
index 0000000..f837b5d
--- /dev/null
+++ b/Laboratory-3/pi_taylor_parallel.cc
@@ -0,0 +1,54 @@
+#include <iomanip>
+#include <iostream>
+#include <numeric>
+#include <string>
+#include <thread>
+#include <utility>
+#include <vector>
+
+using my_float = long double;
+
+void
+pi_taylor_chunk(std::vector<my_float> &output,
+        size_t thread_id, size_t start_step, size_t stop_step) {
+
+
+
+}
+
+std::pair<size_t, size_t>
+usage(int argc, const char *argv[]) {
+    // read the number of steps from the command line
+    if (argc != 3) {
+        std::cerr << "Invalid syntax: pi_taylor <steps> <threads>" << std::endl;
+        exit(1);
+    }
+
+    size_t steps = std::stoll(argv[1]);
+    size_t threads = std::stoll(argv[2]);
+
+    if (steps < threads ){
+        std::cerr << "The number of steps should be larger than the number of threads" << std::endl;
+        exit(1);
+
+    }
+    return std::make_pair(steps, threads);
+}
+
+int main(int argc, const char *argv[]) {
+
+
+    auto ret_pair = usage(argc, argv);
+    auto steps = ret_pair.first;
+    auto threads = ret_pair.second;
+
+    my_float pi;
+
+    // please complete missing parts
+
+
+    std::cout << "For " << steps << ", pi value: "
+        << std::setprecision(std::numeric_limits<long double>::digits10 + 1)
+        << pi << std::endl;
+}
+
diff --git a/Laboratory-3/pi_taylor_sequential.cc b/Laboratory-3/pi_taylor_sequential.cc
new file mode 100644
index 0000000..069976e
--- /dev/null
+++ b/Laboratory-3/pi_taylor_sequential.cc
@@ -0,0 +1,26 @@
+#include <iomanip>
+#include <iostream>
+
+// Allow to change the floating point type
+using my_float = long double;
+
+my_float pi_taylor(size_t steps) {
+    return 0.0f;
+}
+
+int main(int argc, const char *argv[]) {
+
+    // read the number of steps from the command line
+    if (argc != 2) {
+        std::cerr << "Invalid syntax: pi_taylor <steps>" << std::endl;
+        exit(1);
+
+    }
+
+    size_t steps = std::stoll(argv[1]);
+    auto pi = pi_taylor(steps);
+
+    std::cout << "For " << steps << ", pi value: "
+        << std::setprecision(std::numeric_limits<my_float>::digits10 + 1)
+        << pi << std::endl;
+}
diff --git a/README.md b/README.md
index 7a55285..c0cd44a 100644
--- a/README.md
+++ b/README.md
@@ -3,6 +3,27 @@
 Official repository of the Programming and Architecture of Computing Systems
 course of the MS in Robotics, Graphics, and Computer Vision
 
+## Platform support
+
+The code examples and some laboratories rely on
+[cmake](https://cmake.org/overview/) to enable multi-platform building support,
+so there is no need to manually write any Makefile or other build system. Linux
+is the prefered operating system to work on the labs, but the binaries have
+been also compiled on mac OS.
+
+Although, we do not provide support for Windows. If you want to build and run
+the test on Windows, please consider using [CMake with Visual
+Studio](https://docs.microsoft.com/es-es/cpp/build/cmake-projects-in-visual-studio?view=vs-2019).
+
+You can download the free community edition of [Visual Studio
+2019](https://visualstudio.microsoft.com/downloads/), and then with you github
+creentials download this repo and compile it.
+
+One advantage of cmake is the separation between source and binary files. To
+generate the programs, you always have to create a build directory first, then
+invoke cmake to generate the build files, `Makefiles` for Linux, and, after
+than, use the standard `make` tool for obtaining the binaries. By default, cmake builds programs in release mode with optimizations enabled, if you want to build them with debug support; e.g., to use them with `gdb`, you can set the variable `CMAKE_BUILD_TYPE` to `Debug`.
+
 ## Code snippets from Class
 
 The directory `code_examples` contains many of the small C++ programs and
@@ -11,18 +32,27 @@ fragments from the slides.
 To compile them, you can use `cmake`. For example:
 
 ```bash
-cd code_examples
-mkdir build
-cd build
+mkdir build-release
+cd build-release
 cmake ../ # generate the Makefile with cmake
 make # compile the examples
 ls # list the examples
 ```
 
-Although, we do not provide support for Windows. If you want to build and run
-the test on Windows, please consider using [CMake with Visual
-Studio](https://docs.microsoft.com/es-es/cpp/build/cmake-projects-in-visual-studio?view=vs-2019).
+If you want to compile for debugging, please note that at this point, we will
+have two sets of binaries, set the variable `CMAKE_BUILD_TYPE` when calling
+`cmake`:
+
+```bash
+mkdir build-debug
+cd build-debug
+cmake -DCMAKE_BUILD_TYPE=Debug ../ # generate the Makefile with cmake
+make -j4 # compile the examples in parallel with 4 jobs
+```
+
+## Laboratories
+
+Each laboratory includes its own directory, but all of them can be built at the
+same time if required. To build a single laboratory; e.g., the third laboratory, you can invoke c
+
 
-You can download the free community edition of [Visual Studio
-2019](https://visualstudio.microsoft.com/downloads/), and then with you github
-creentials download this repo and compile it.
diff --git a/cmake/AddPacsExecutable.cmake b/cmake/AddPacsExecutable.cmake
new file mode 100644
index 0000000..e4d9a6d
--- /dev/null
+++ b/cmake/AddPacsExecutable.cmake
@@ -0,0 +1,9 @@
+macro(ADD_PACS_EXECUTABLE)
+    set(options "")
+    set(oneValueArgs TARGET KERNEL)
+    set(multiValueArgs SOURCES)
+    cmake_parse_arguments(ADD_PACS_EXECUTABLE "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN} )
+
+    add_executable("${ADD_PACS_EXECUTABLE_TARGET}" ${ADD_PACS_EXECUTABLE_SOURCES})
+    target_link_libraries("${ADD_PACS_EXECUTABLE_TARGET}"  Threads::Threads)  
+endmacro(ADD_PACS_EXECUTABLE)
diff --git a/code_examples/CMakeLists.txt b/code_examples/CMakeLists.txt
index b6603b2..ed8748c 100644
--- a/code_examples/CMakeLists.txt
+++ b/code_examples/CMakeLists.txt
@@ -1,35 +1,9 @@
-cmake_minimum_required (VERSION 3.1)
-project (PACS_EXAMPLES)
-
-set(CMAKE_CXX_STANDARD 11)
-set(CMAKE_CXX_STANDARD_REQUIRED ON)
-
-set(CMAKE_THREAD_PREFER_PTHREAD TRUE)
-set(THREADS_PREFER_PTHREAD_FLAG TRUE)
-find_package(Threads REQUIRED)
-
-if (MSVC)
-    # warning level 4 and all warnings as errors
-    add_compile_options(/W4 /WX)
-else()
-    # lots of warnings and all warnings as errors
-    add_compile_options(-Wall -Wextra -pedantic -Werror)
-endif()
-
-#FIXME add macro for the two steps
-add_executable(hello_pacs hello_pacs.cc)
-target_link_libraries(hello_pacs Threads::Threads)
-add_executable(thread_joinable thread_joinable.cc)
-target_link_libraries(thread_joinable Threads::Threads)
-add_executable(hello_pacs_two_threads hello_pacs_two_threads.cc)
-target_link_libraries(hello_pacs_two_threads Threads::Threads)
-add_executable(hello_pacs_args hello_pacs_args.cc)
-target_link_libraries(hello_pacs_args Threads::Threads)
-add_executable(lambda_example lambda_example.cc)
-add_executable(saxpy saxpy.cc)
-target_link_libraries(saxpy Threads::Threads)
-add_executable(saxpy_scaling saxpy_scaling.cc)
-target_link_libraries(saxpy_scaling Threads::Threads)
-
-add_executable(synchronization synchronization.cc)
-target_link_libraries(synchronization Threads::Threads)
+ADD_PACS_EXECUTABLE(TARGET hello SOURCES hello_pacs.cc)
+ADD_PACS_EXECUTABLE(TARGET thread_joinable SOURCES thread_joinable.cc)
+ADD_PACS_EXECUTABLE(TARGET hello_pacs_two_threads SOURCES hello_pacs_two_threads.cc)
+ADD_PACS_EXECUTABLE(TARGET hello_pacs_args SOURCES hello_pacs_args.cc)
+ADD_PACS_EXECUTABLE(TARGET lambda_example SOURCES lambda_example.cc)
+ADD_PACS_EXECUTABLE(TARGET saxpy SOURCES saxpy.cc)
+ADD_PACS_EXECUTABLE(TARGET saxpy_scaling SOURCES saxpy_scaling.cc)
+ADD_PACS_EXECUTABLE(TARGET synchronization SOURCES synchronization.cc)
+ADD_PACS_EXECUTABLE(TARGET mutex SOURCES mutex.cc)
diff --git a/code_examples/mutex.cc b/code_examples/mutex.cc
new file mode 100644
index 0000000..39b4259
--- /dev/null
+++ b/code_examples/mutex.cc
@@ -0,0 +1,25 @@
+#include <iostream>
+#include <mutex>
+#include <thread>
+
+namespace {
+
+    std::mutex m;
+    int shared_var = 0;
+}
+
+void increment() {
+    m.lock();
+    ++shared_var;
+    m.unlock();
+}
+
+int main() {
+    std::thread t0{increment};
+    std::thread t1{increment};
+
+    t0.join();
+    t1.join();
+
+    std::cout << shared_var << std::endl;
+}
diff --git a/code_examples/pi_taylor b/code_examples/pi_taylor
new file mode 100755
index 0000000..78c3ae3
Binary files /dev/null and b/code_examples/pi_taylor differ
diff --git a/code_examples/snippet_mutex.cc b/code_examples/snippet_mutex.cc
new file mode 100644
index 0000000..5ed21bf
--- /dev/null
+++ b/code_examples/snippet_mutex.cc
@@ -0,0 +1,10 @@
+#include <mutex>
+
+std::mutex m;
+int shared_var = 0;
+
+void increment() {
+    m.lock();
+    ++shared_var;
+    m.unlock();
+}
diff --git a/code_examples/snippet_mutex_exception.cc b/code_examples/snippet_mutex_exception.cc
new file mode 100644
index 0000000..f8de009
--- /dev/null
+++ b/code_examples/snippet_mutex_exception.cc
@@ -0,0 +1,13 @@
+#include <mutex>
+
+std::mutex m;
+int shared_var = 0;
+
+void increment() {
+
+    int* siete = new int(7);
+
+    m.lock();
+    ++shared_var;
+    m.unlock();
+}