Initial commit that has most of what I need.

main.cpp

@@ -0,0 +1,39 @@
+#include <iostream>
+
+#include <ftxui/dom/elements.hpp>
+#include <ftxui/screen/screen.hpp>
+#include <ftxui/screen/string.hpp>
+
+int main() {
+  using namespace ftxui;
+
+  auto summary = [&] {
+    auto content = vbox({
+        hbox({text(L"- done:   "), text(L"3") | bold}) | color(Color::Green),
+        hbox({text(L"- active: "), text(L"2") | bold}) | color(Color::RedLight),
+        hbox({text(L"- queue:  "), text(L"9") | bold}) | color(Color::Red),
+    });
+    return window(text(L" Summary "), content);
+  };
+
+  auto document =  //
+      vbox({
+          hbox({
+              summary(),
+              summary(),
+              summary() | flex,
+          }),
+          summary(),
+          summary(),
+      });
+
+  // Limit the size of the document to 80 char.
+  document = document | size(WIDTH, LESS_THAN, 80);
+
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
+  Render(screen, document);
+
+  std::cout << screen.ToString() << '\0' << std::endl;
+
+  return EXIT_SUCCESS;
+}