Melanite is a universal, user-programmable soft PLC. Wire up real-time control logic, industrial protocols, smart-home, a touch HMI and a live spatial 3D editor — directly on the device. No developer toolchain. No deployment step.
Free, forever, for personal use.
Why it exists
Node-RED runs on an event loop, not a real-time cycle. CODESYS is programmed in a desktop IDE. Home Assistant has no real-time control and no EtherCAT. WLED drives light, not logic. Melanite is one coherent system that does all of it, on a €50 compute module, with no IDE and no deployment step.
It runs offline by default: no account, no cloud service, no telemetry, no phone-home. The licence verifies on the device itself.
The real-time core, measured
Every controller claims to be real-time. Melanite measures itself and publishes the histograms on the device, so you can check this table on your own hardware instead of believing it.
The figures below come from one continuous window on a Raspberry Pi CM5 driving four EtherCAT slaves — not a lab bench set up for the occasion.
| Quantity | Measured | Unit | Conditions |
|---|---|---|---|
| Cycles executed | 104,031,000 | 28.9 h continuous, 1 kHz, EtherCAT in OP | |
| Missed deadlines | 0 | Across all 104 million | |
| Deadline jitter, median | 0.256 | µs | Same window |
| Deadline jitter, p99.9 | 1.28 | µs | Same window |
| Deadline jitter, worst | 150.8 | µs | Rarest excursion; 15% of the 1 ms budget |
| Wake latency, p99.9 | 22.8 | µs | Cyclictest-equivalent, same window |
| RT-thread allocations | 0 | bytes | Tripwire armed the whole window |
| Stall events | 0 | Same window |
Raspberry Pi CM5, PREEMPT_RT, four EtherCAT slaves in OP, one uninterrupted window. The cycle is configurable down to 250 µs, but we have no benchmark at that rate, so it is not claimed as verified.
What it does
No add-on packs, no per-protocol licences, no feature gates between tiers. The status column is the honest one.
On a live device
One binary serves the engineering view, the operator's view and the house. These are screenshots of it running, not renderings of it.
Field record
A lab reactor controller had been commissioned from a professional CODESYS integrator: €10k, months of lead time, and an interface nobody could change afterwards. Working through Melanite's agent API, an AI agent rebuilt it — a ΔT-clamped cascade PID, a multi-segment setpoint program, real EtherCAT I/O and a purpose-built operator page — in roughly an hour, editable ever since.
Our own lab project, not a customer deployment.
The Community tier is the whole platform, free for private use. Any use by a business needs a Commercial licence — a machine you sell, and just as much a test rig, a production line, a dashboard or a building you run in-house. One build runs every tier; the licence toggles entitlements, never the feature set.