strict digraph {
  graph [
    splines=true,
  ]
  node [
    style="filled",
    fontname="sans-serif",
    color="#3fa687",
    fillcolor="#275a4b",
    fontcolor="white",
    shape="box",
    penwidth=2,
    width=4.1,
  ];
  edge [
    color="#3fa687",
    fontcolor="#275a4b",
    fontname="sans-serif",
    penwidth=2,
    labelfloat=true,
  ];

  Start [shape="Mrecord", width=0.75];
  End [
    label="Blink the LEDs",
    tooltip="Blink the LEDs",
    shape="Mrecord",
    URL="https://github.com/RIOT-OS/RIOT/tree/master/tests/leds",
  ];

  IfCPU [
    label=<CPU/MCU<BR/>already ported?>,
    tooltip="CPU/MCU already ported?",
    shape="diamond",
  ];
  IfBoard [
    label=<Board definitions<BR/>already provided?>,
    tooltip="Board definitions already provided?",
    shape="diamond",
  ];
  IfDrivers [
    label=<All on-board<BR/>devices supported?>,
    tooltip="All on-board devices supported?",
    shape="diamond",
  ];
  IfNetdev [
    label=<Network device<BR/>supported by<BR/>network stack?>,
    tooltip="Network device supported by network stack?",
    shape="diamond"
  ];

  PortCPU [
    label=<Port <B>CPU</B><BR/>(TBD: provide guide)>,
    tooltip="Port CPU",
  ];
  PortBoard [
    label=<Provide<BR/><B>board definitions</B>>,
    tooltip="Provide board definitions",
    URL="@ref porting-boards",
  ];
  PortDrivers [
    label=<Provide<BR/><B>device drivers</B>>,
    tooltip="Provide device drivers",
    URL="@ref driver-guide",
  ];
  PortNetdev [
    label=<Provide <B>network device support</B><BR/>for network stack>,
    tooltip="Provide network device support for network stack",
    URL="@ref drivers_netdev",
  ];

  Start -> IfCPU;
  IfCPU -> IfBoard [label="Yes"];
  IfBoard -> IfDrivers [label="Yes"];
  IfDrivers -> IfNetdev [label="Yes"];
  IfNetdev -> End [label="Yes"];

  IfCPU -> PortCPU [label="No"];
  IfBoard -> PortBoard [label="No"];
  IfDrivers -> PortDrivers [label="No"];
  IfNetdev -> PortNetdev [label="No"];

  PortCPU -> IfBoard;
  PortBoard -> IfDrivers;
  PortDrivers -> IfNetdev;
  PortNetdev -> End;

  /* ensure No branch is on same row as If */
  {rank=same; IfCPU PortCPU}
  {rank=same; IfBoard PortBoard}
  {rank=same; IfDrivers PortDrivers}
  {rank=same; IfNetdev PortNetdev}
  /* ensure PortNodes are on top of each other */
  edge [style="invis"];
  PortCPU -> PortBoard -> PortDrivers -> PortNetdev;
}