KTREM
Kryon terminal emulator ktrem

ktrem

A Kryon-built terminal for Linux desktops. The target is simple: become a practical xfce4-terminal alternative with fast output, familiar tabs, rich terminal compatibility, and honest public benchmarks.

View benchmarks Parity matrix Build locally
ktrem - benchmarks
1: shell 2: build 3: logs 
$ ktrem -x make test --tab
ok terminal

$ make benchmark-parser
ansi_flood        27 ms
unicode_table      7 ms
dense_sgr         13 ms
resize_reflow    739 ms

Alt+1..Alt+8 switch tabs directly.
Faster on current GUI suite ktrem beats xfce4-terminal average time in every measured synthetic output workload.
External workflows measured ktrem averages 158.7 ms on live resize, 206.3 ms on clipboard paste, and 613.0 ms on find workflow under Xvfb.
Built on Kryon The terminal app lives in ktrem; reusable runtime work stays in Kryon.

Benchmarks

Measured against xfce4-terminal

The GUI suite runs both terminals inside Xvfb so it does not interrupt the active desktop. Results are averaged across three isolated runs with KTREM_ACTIVE_FPS=1000 and KTREM_PTY_BURST_MS=8. The clipboard and find workloads send the same held shortcuts to both terminals.

Workload ktrem avg xfce4-terminal avg State
Startup payload0.0 ms1.7 msmatched
ANSI flood, 18k lines81.7 ms187.0 msfaster
Unicode table, 6k lines18.0 ms93.0 msfaster
Alternate-screen redraw22.3 ms61.0 msfaster
Dense SGR styling84.0 ms91.3 msfaster avg
Long wrapped output42.7 ms114.0 msfaster
Scrollback flood86.7 ms107.7 msfaster
Cursor matrix updates72.7 ms124.3 msfaster
External clipboard paste206.3 ms256.7 msfaster
External find dialog613.0 ms635.7 msfaster avg
Paste-like burst 69.3 ms

xfce4-terminal measured 154.7 ms on the same synthetic workload.

Hyperlink grid 76.7 ms

OSC 8 link-heavy output, compared with xfce4-terminal at 276.7 ms.

Resize replay 739 ms

Parser-only repeated reflow improved from 2393 ms after streaming reflow work.

Live resize 158.7 ms

120 external X window resizes under Xvfb; xfce4-terminal averaged 177.3 ms.

Clipboard paste 206.3 ms

29-line X clipboard payload pasted with Ctrl+Shift+V into a raw-mode target; xfce4-terminal averaged 256.7 ms.

Find workflow 613.0 ms

Ctrl+Shift+F over an 18k-line corpus, submit, close, and return to PTY input; xfce4-terminal averaged 635.7 ms.

Parity

Close, but not declared done

ktrem is already competitive on synthetic throughput and has a large terminal-compatibility surface. The remaining work is about server/drop-down behavior, packaging, and broader real-desktop validation.

Implemented

  • Tabs with Alt+1 through Alt+8 direct switching.
  • Search across scrollback and visible terminal content.
  • Copy, paste, primary selection, bracketed paste, and OSC 52 clipboard handling.
  • OSC 8 hyperlinks with Ctrl-click opening.
  • Profiles, font path, font size, colors, scrollback, cursor style, and session restore.
  • Sixel images, mouse reporting, alternate screen, xterm title/color controls, and XTGETTCAP reports.

Xfce launch coverage

  • --command, -e, --execute, and -x.
  • --working-directory, --default-working-directory, --title, and --geometry.
  • --fullscreen, --maximize, --drop-down, and border visibility flags.
  • --tab multi-spec launch up to the current 8-tab session limit.

Remaining before a full alternative claim

  • Broader workflow validation beyond the current Xvfb benchmark suite.
  • Broader live-resize validation across real desktop window managers.
  • Real multi-window launch and single-instance command server behavior.
  • Repeated-invocation drop-down visibility toggle.
  • Fontconfig-backed fallback for missing glyphs beyond static fallback paths.
  • Desktop file, icon packaging, release assets, and terminfo decision.

Features

Built for real terminal work

Fast output path

PTY output uses an adaptive active-output cadence and bounded drain burst to keep heavy shell output moving without locking the idle UI to a high frame rate.

Familiar keyboard model

Tab navigation, copy/paste, find, zoom, page scrolling, and direct tab switching follow the shortcuts terminal users expect.

Terminal compatibility

SGR styling, alternate screen, mouse modes, focus reporting, sixel, xterm OSC controls, modifyOtherKeys, and DEC private reports are covered in the parser.

Kryon integration

The app uses Kryon for windowing, rendering, input, system theme integration, and platform hooks while keeping terminal-specific behavior in ktrem.

Install

Build ktrem locally

ktrem currently builds from source against a neighboring Kryon checkout. Install commands and package links will move here as release assets become available.

git clone https://github.com/kryonlabs/kryon.git
git clone https://github.com/kryonlabs/ktrem.git
cd ktrem
make
make test
make install

Roadmap

Remaining engineering plan

1

Broaden benchmark coverage

Add longer real-desktop workflow runs beside the existing output, clipboard paste, find, and live-resize Xvfb suites.

2

Close launch/server parity

Add real separate windows, single-instance command routing, and drop-down toggle behavior.

3

Fix missing glyphs completely

Add fontconfig fallback so box drawing, Powerline, CJK, symbols, Greek, and Cyrillic can resolve from installed system fonts.

4

Move renderer work into Kryon where reusable

Keep ktrem logic in ktrem, but add reusable Kryon primitives for a retained GPU terminal-grid renderer when the design is proven.