diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..bacf02c
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+/build/
+/main
diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..64447de
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,19 @@
+cmake_minimum_required(VERSION 3.28)
+
+project(cmake_exercise)
+
+find_package(Boost REQUIRED COMPONENTS filesystem)
+find_package(deal.II REQUIRED)
+find_package(yaml-cpp REQUIRED)
+
+add_executable(main
+    main.cpp
+    filesystem/filesystem.cpp
+    flatset/flatset.cpp
+    fem/fem.cpp
+    yamlParser/yamlParser.cpp
+)
+
+target_link_libraries(main ${Boost_LIBRARIES} yaml-cpp)
+
+deal_ii_setup_target(main)
diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..840a269
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,22 @@
+FROM ubuntu:24.04
+
+RUN apt-get update && apt-get install -y \
+    # Packages recommended by the exercise:
+    build-essential cmake unzip wget vim \
+    # Boost filesystem:
+    libboost-all-dev \
+    # deal.II:
+    libdeal.ii-dev
+
+# yaml-cpp from apt:
+# RUN apt-get update && apt-get install -y libyaml-cpp-dev
+
+# yaml-cpp from source:
+RUN mkdir yaml-cpp && cd yaml-cpp && \
+    wget https://github.com/jbeder/yaml-cpp/archive/refs/tags/yaml-cpp-0.6.3.tar.gz && \
+    tar --extract -f yaml-cpp-0.6.3.tar.gz && \
+    cd yaml-cpp-yaml-cpp-0.6.3 && mkdir build && cd build && \
+    cmake -DYAML_BUILD_SHARED_LIBS=ON .. && make && make install && \
+    cd ../../.. && rm -rf yaml-cpp
+
+WORKDIR /mnt/host/
diff --git a/main.cpp b/main.cpp
index 7588360..ba913dc 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,39 +1,39 @@
-//#include "fem/fem.hpp"
-//#include "flatset/flatset.hpp"
-//#include "filesystem/filesystem.hpp"
-//#include "yamlParser/yamlParser.hpp"
+#include "fem/fem.hpp"
+#include "flatset/flatset.hpp"
+#include "filesystem/filesystem.hpp"
+#include "yamlParser/yamlParser.hpp"
 #include <iostream>
 
 int main(int argc, char *argv[])
 {
   std::cout << "Let's fight with CMake, Docker, and some dependencies!" << std::endl << std::endl;
 
-  //std::cout << "Solve Poisson problem with FEM using deal.II" << std::endl;
-  //Fem fem;
-  //fem.run();
-  //std::cout << std::endl;
+  std::cout << "Solve Poisson problem with FEM using deal.II" << std::endl;
+  Fem fem;
+  fem.run();
+  std::cout << std::endl;
 
-  //std::cout << "Modify a flat set using boost container" << std::endl;
-  //modifyAndPrintSets();
-  //std::cout << std::endl;
+  std::cout << "Modify a flat set using boost container" << std::endl;
+  modifyAndPrintSets();
+  std::cout << std::endl;
 
-  //std::cout << "Inspect the current directory using boost filesystem" << std::endl;
-  //inspectDirectory();
-  //std::cout << std::endl;
+  std::cout << "Inspect the current directory using boost filesystem" << std::endl;
+  inspectDirectory();
+  std::cout << std::endl;
 
   
-  //if ( argc == 2 )
-  //{
-  //  const std::string yamlFile( argv[1] );
-  //  std::cout << "Parse some yaml file with yaml-cpp" << std::endl;
-  //  std::cout << "  " << yamlFile << std::endl;
-  //  parseConfig( yamlFile );
-  //}
-  //else
-  //{
-  //  std::cout << "To parse a yaml file please specify file on command line" << std::endl;
-  //  std::cout << "  ./main YAMLFILE" << std::endl;
-  //}
+  if ( argc == 2 )
+  {
+   const std::string yamlFile( argv[1] );
+   std::cout << "Parse some yaml file with yaml-cpp" << std::endl;
+   std::cout << "  " << yamlFile << std::endl;
+   parseConfig( yamlFile );
+  }
+  else
+  {
+   std::cout << "To parse a yaml file please specify file on command line" << std::endl;
+   std::cout << "  ./main YAMLFILE" << std::endl;
+  }
 
   return 0;
 }