Minlog is an interactive proof system based on first order natural deduction calculus. You can also use a native VNC viewer instead of this in-browser viewer. This webpage once was an online version of Minlog, served to you by Valentin Herrmann and based of the excellent Agdapad, which was made by Ingo Blechschmidt for an Agda course at the University of Padova, building on awesome free technology: