jprototerm

JavaFX canvas terminal prototype using jlibghostty for terminal emulation and Nix for the build environment. It builds a plain JavaFX application (JDK 25, JavaFX 25 via Gradle) packaged as a Nix derivation — no GraalVM/GluonFX native image.

Build

nix build
./result/bin/jprototerm

Install it into a profile (works on NixOS and on a plain Debian box with Nix installed):

nix profile add .
jprototerm

The flake bundles everything the app needs — the JDK 25 runtime, the Maven JavaFX modules and their native libraries, and the gtk/glib/freetype/X11 libraries they load — except the system OpenGL/graphics drivers. libGL is supplied by the host at runtime through a GL shim in the launcher wrapper, so the same closure runs against NixOS, Mesa, or vendor (e.g. NVIDIA) GPU drivers.

Gradle dependencies are vendored in deps.json for the pure Nix sandbox. Regenerate it after changing dependencies in build.gradle (the update script writes deps.json in the current directory):

$(nix build .#gradleDepsUpdateScript --no-link --print-out-paths)

For development:

nix develop
gradle run

The Gradle project is the source of truth for the JavaFX build.

Config

Configuration is read from:

$XDG_CONFIG_HOME/jprototerm/config.toml

If XDG_CONFIG_HOME is unset, the fallback is:

$HOME/.config/jprototerm/config.toml

If no config file exists, jprototerm writes the default config on startup.

Example, also available in config.example.toml:

[terminal]
columns = 100
rows = 30
shell = "/bin/bash"
font_family = "JetBrainsMono Nerd Font"
font_size = 15

[window]
width = 1200
height = 760

[kitty_graphics]
enabled = true

[scrollback]
editor_command = "vi {file}"

[env.override]
ZELLIJ_SESSION_NAME = ""

[keybindings]
navigate_left = "ALT+H"
navigate_down = "ALT+J"
navigate_up = "ALT+K"
navigate_right = "ALT+L"
toggle_floating = "ALT+F"
new_floating = "ALT+SHIFT+F"
next_floating = "ALT+F12"
close_pane = "ALT+X"
open_font_selector = "ALT+T"
open_scrollback = "ALT+S"

Defaults

• Alt+h/j/k/l: navigate panes
• Alt+f: show or hide all floating panes
• Alt+Shift+f: create a new floating pane
• Alt+F12: cycle floating panes
• Alt+x: close the active floating pane
• Alt+t: open the font selector
• Alt+s: open the active pane scrollback in $EDITOR
• Font default: JetBrainsMono Nerd Font
• Kitty graphics protocol parsing is enabled by default