RungCraft
PLC logic in a browser tab, with a simulator that actually scans.
Ladder and structured text in one project, a Web Worker scan cycle with live energy flow, plus HMI screens and recipes. No install, no backend — open the folder and work.
Free during launch Every build on this site is free during the launch period. Paid editions and App Store listings come later; nothing here needs an account or a key.
LAD · ST Any modern browser Open core (MIT) Engineering v0.3.0
01What's inside
The specifics, with numbers.
The things a general-purpose tool does not do.
01
LAD and ST, block by block
Mix ladder and structured text in the same program; FCs and FBs are callable across both languages.
02
A real scan cycle
Simulation runs in a Web Worker with run, pause, step, stop and reset, a scan-time readout, speed multiplier and forcing.
03
Five demos to learn from
Motor start-stop with HMI, a traffic light (TON + CTU), conveyor counting, an ST traffic light, and a tank with FB + DB + UDT + analog, HMI and recipe.
04
HMI and recipes included
Buttons, switches, lamps, numeric display and input, text and bar graphs bound to PLC tags; recipe tables download, capture and export CSV or JSON.
05
Projects that persist
Stored in IndexedDB and portable as .ladproj.json, with a Zod-versioned schema and migrations.
06
One small archive
The whole app is a 992 KB download, and the open core is MIT-licensed for teaching and evaluation.
02Gallery
A closer look.
Real screenshots where they exist. Where a capture is missing, the frame says so.
Screenshot pending
Editor capture in preparation — the current UI is Chinese-first.
The build is real; the picture will follow.
Screenshot pending
Simulator and forcing panel.
The build is real; the picture will follow.
03Get it
Download the build.
Everything is free during launch — the same binaries the studio tests. No account, no key.
Free during launch Every build on this site is free during the launch period. Paid editions and App Store listings come later; nothing here needs an account or a key.
macOS builds are Developer ID signed and notarised by Apple. Checksums are published with the release manifest.
Artifacts over the Pages file limit stay pending until the binary bucket is live. Ask and we will send those directly.
UI language
The editor is Chinese-only today. An English pass is planned; the site does not claim it is localised.
macOS launcher
rungcraft-0.3.0.zip
1.0 MB
04More from the bench
Keep looking around.
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