DEJA.JSIOStandard hardware. Full control.
Expand your layout with hardware you already own. Arduinos, ESP32s, Pico Ws, and MQTT — no proprietary modules to buy.
Your layout, your hardware, your rules
Arduino, ESP32, and Pico W support
Plug-and-play firmware for Arduino Mega, ESP32 (USB or WiFi/MQTT), and Raspberry Pi Pico W. Drop the sketch on, wire it up, and your devices register themselves with the server on boot.
MQTT native
Every IO device speaks MQTT directly to your server. Subscribe to events, publish commands, compose anything.
Effects, sensors, servos, signals
Wire LED strips, occupancy sensors, servo turnouts, and signals — each one becomes a first-class element in Cloud.
No proprietary modules
Skip expensive proprietary decoders for things a Pico W can do for a few dollars. Standard hardware, full control.
Standard hardware, end to end
Wire it yourself or drop in one of these. Every device speaks MQTT directly to your server.
Raspberry Pi Pico W with DEJA firmware
Arduino Mega wired for effects
ESP32 board wired for wireless IO
Servo-driven turnout mechanism
LED strip lighting a station scene
Occupancy sensor on the mainline
Signal head wired to IO
MQTT to the server. DCC to the track. Open protocols in between.
Every IO device — ESP32, Pico W, WLED, or something you built yourself — publishes its state and subscribes to commands over MQTT. The server routes messages to the right Cloud element. You never touch a proprietary module or a locked-down protocol.
LED strips to servo turnouts. If you can wire it, you can run it.
If it runs on an Arduino, an ESP32, or a Pico W, it can run under DEJA.js. Flash our firmware with deja deploy, wire it up, and it shows up in Cloud.
- WLED-flashed LED scene lighting
- Servo-driven turnouts
- Block occupancy sensors
- Signal heads
- Anything else you can wire to a GPIO
Sign in once. Use everything.
DEJA.js isn't a single tool — it's a connected platform for driving, managing, and expanding your layout.
Free plan. No trial timer.
Spin up DEJA.js on your layout today — no credit card, no download for the web apps.
Build it your way.
Standard boards, open protocols. Start with an Arduino or a Pico W.