From the link in his question he mentions; > Many other software engineers have also complained to me and expect me to take action. If that's correct, then ye

From the link in his question he mentions; > Many other software engineers have also complained to me and expect me to take action. If that's correct, then yes, you have to fire, otherwise it will turn the whole team toxic. Nothing breeds mistrust and resentment like having a co-worker where you feel you're picking up the slack for them.