Apps built from the ground up.

One library, every platform. A network lab, an image editor, a kanban board and a backup suite, each with its own face, all on JFLib.

Explore the apps What is JFLib?

Apps: 4 in development, 5 planned
Platforms: Windows · Linux · Android · Web
Foundation: JFLib, written from scratch in Rust

Four apps, each with its own face

Every app has its own site in its own style, from the sober network lab to the blue kanban board. What they share is underneath, and the bar at the top that brings you back here.

JFNetworker in the light theme: the device palette, a campus network and the properties of the layer-3 switch MLS1 with its ports.

JFNetworkernetworker.jfreund.orgNetwork simulator and lab: build networks, configure devices in their consoles and watch every packet. With an academy and a lab for distributed systems.In developmentWindowsLinux

JFPainter, still named PaintCraft in its title bar, with a drawing in three layers and the Tools, Colors, History and Layers panels.

JFPainterpainter.jfreund.orgImage editor with layers, brushes, effects, many image formats and plugins. On the desktop, in the browser and on Android.In developmentWindowsLinuxWebAndroid

Kanban Tasker in its dark blue theme with five columns of task cards.

Kanban Taskerkanban.jfreund.orgPersonal kanban boards in one local file, synced by the tool you already use. Moving to JFLib: same look, more platforms.In developmentWindowsLinuxAndroidiOSmacOS

JFBackup in the light theme, still named BackupCraft in its title bar, with the overview and demo data.

JFBackupbackup.jfreund.orgBackup suite with its own server and agents: deduplicated, encrypted and signed backups, schedules, replication and restore.In developmentWindowsLinux

Coming later Planned

JFScriptscript.jfreund.orgA scripting language with its own virtual machine, editor support and debugger.
JFDiagrammerdiagrammer.jfreund.orgDiagrams, flowcharts and sketches of systems.
3D Engine3d.jfreund.orgA 3D engine on the GPU layer of JFLib.
2D Renderer2d.jfreund.orgA fast 2D renderer for apps and games.
Game Toolsgame.jfreund.orgTools and an engine for making games.

One library under every app

jflib.org

JFLib is a GUI library written from scratch in Rust. It draws every pixel itself, needs no standard library and brings the same app to Windows, Linux, Android and the browser.

That is why a network simulator, an image editor and a backup suite can share one foundation, and why each of them can still look exactly the way it wants.

JFNetworkerJFPainterKanban TaskerJFBackup

JFLibRust · no_std · GPU · accessibility · themes

WindowsLinuxAndroidWebmacOSiOS

Four apps, one foundation. Dashed: planned platforms.

What happens next

A short look ahead. Every app site has its own roadmap with the details.

The whole roadmap

Now November 2026

JFNetworkerThe lab for distributed systems: sweeps and a database service
Kanban TaskerMoving the app onto JFLib, with the same look
jfreund.orgPhase 2: the sites as a Next.js app

JFPainterThe new name in the app
JFBackupPublic packages for Windows and Linux
JFNetworkerReplication, traffic steering and a course about scaling

Later

Kanban TaskeriOS and macOS
jfreund.orgA forum and more services
JFScript · 3D · 2D · GamesNew app sites as the apps take shape

From the workshop

What changed lately, across all apps.

All news

8 Nov 2026jfreund.org

First drafts for jfreund.org and its app sites

One portal, one subdomain per app, each in its own style, joined by a shared bar.

4 Nov 2026JFNetworker

Two academy courses ready to install

“Network basics” and “Fault finding in networks” install straight from GitHub, in German and English.

3 Nov 2026JFNetworker

Lab experiments in the window

Load sweeps and studies of the lab for distributed systems now run right in the app, with their charts.