3 releases

0.0.3 Jun 26, 2020
0.0.2 Jun 24, 2020
0.0.1 Jun 22, 2020

#638 in Unix APIs


265 lines


Gel-O is a library for manipulating user-input in Linux.

Gel-O can make your computer feel like Jell-O, by delaying all user input by a configurable number of milliseconds (and in various other ways).


Gel-O is experimental. Expect many breaking changes to come.


For fun, and to get my feet wet.


  • Linux
    • epoll (Linux 2.6.27+)
    • evdev kernel (approximately Linux 2.4+)
  • Rust toolchain
    • version 1.34 or higher
  • Transitive dependencies
    • C toolchain
    • autoconf and libtool
      • #apt install autoconf libtool
      • #yum install autoconf libtool
      • #pacman -S autoconf libtool

macOs and Windows are not supported at this time.

BSD support may be easy to add, as evdev was recently added to some BSD kernels


  • Configurable delay
  • Works on Xorg, Wayland, and the Linux virtual terminal
  • Runs smoothly on low power devices like raspberry pi due to efficient epoll-based architecture
  • Works with every input device Linux does including mice, keyboards, power buttons, gamepads, flight sticks and more


  • Requires read/write access to files in /dev/input, /dev/uinput

How to use

Download the source

git clone [this repo]

Compile the source. You need a rust toolchain and cargo.

cargo build --release --example delay

Run the produced binary with root privledges

sudo ./target/release/examples/delay [number of ms to delay]


  • monitor filesystem for new devices, and add delay to them too (probably using inotify)
  • add tests
  • Create serializable event struct that sidesteps ownership issues with libevdev


~20K SLoC