01
Sign Up
Create your free DEJA Cloud account. Choose a plan that fits your layout. Your roster, settings, and layout data sync instantly across every device.
DEJA.jsDEJA.jsday-ZHAH · jay-ess
Simple to start. Built to grow.
The cloud platform for DCC-EX.
DEJA.js connects your 
DCC-EX EX-CommandStation to your phone, tablet, and computer using a modern, high performance, secure tech stack. Throttle, manage, and automate your layout from any browser — no app store required.
You tap
Server routes
deja — tamarack
$
✓ Ready
← throttle {addr:3, speed:50}
→ <t 3 50 1>
DCC-EX Translates
DCC-EX Translates
Train moves
Train moves
Scroll
Quick Start
Running trains in three steps.
02
Install the Server
Plug in your 
DCC-EX EX-CommandStation via USB and install the CLI. Then run deja login to connect your account, and deja start to launch the server.
bash
$curl -fsSL https://install.dejajs.com | bash
03
Run
Open the Throttle app on any device — phone, tablet, or desktop. Scan the QR code to launch it instantly on your phone.
Scan to open on phone
Scan to open on phone
See It In Action
Watch the 2-minute quickstart
DEJA.js — Getting Started
$ curl -fsSL https://install.dejajs.com | bash
Downloading DEJA Server v1.2.0...
Installing dependencies...
✓ DEJA Server v1.2.0 installed
→ Starting server...
✓ Server running on ws://localhost:8082
✓ EX-CommandStation connected on /dev/ttyUSB0
ℹ Signed in · Layout: Pittsburg & Shasta 1:87
Video coming soon
Check back shortly
~2 min
Throttle App
DEJA.JSThrottle
Precision locomotive control.
Precise speed control, function mapping, EZ Consist, and CV programming — from any browser. No app store, no install. Add it to your homescreen and open it with a tap.
- 🎚️Speed & Direction Smooth 0–126 step control with momentary and toggle functions
- 🚂EZ Consist Build multi-loco consists with independent function control per unit
- 🗂️Roster Snap a photo and AI fills in the roster entry — addresses, names, road numbers, and function mapping
- 🚦Track Diagrams Turnouts, routes, and signals — all automated from a clickable track map
- 🎆Effects, WLED & Sounds Toggle lights and relays, activate WLED scenes, and play your sound library from any device
- ♿Accessible by Design Large, chonky touch targets and four throttle styles to match how you operate. · · ·
- ⚙️CV Programming Read and write decoder CVs directly from the Throttle app
📱
Web App — works on any device
Open throttle.dejajs.com in Safari or Chrome and tap "Add to Homescreen". Full-screen, no browser chrome.
Server + CLI
One command. Everything connects.
The DEJA Server is a lightweight CLI that bridges your DEJA Cloud to your EX-CommandStation. It runs on any computer connected to an EX-CommandStation. Install it once, start it with a single command, and your entire layout — throttles, turnouts, signals, effects — is live.
- 🕹️WiThrottle server — ProtoThrottle, Engine Driver, ThrottleCard, and JMRI-style throttles connect directly
- 🔌USB serial bridge to DCC-EX EX-CommandStation at 115,200 baud
- 📡Connect DEJA IO devices via USB or WiFi — MQTT and WebSockets offer wireless extensibility
- ☁️DEJA Cloud sync — layout commands flow from cloud to track instantly
- 🔐Secure by design — browser-based CLI device authorization, credentials stay on your machine
- 🏗️Robust at scale — dozens of simultaneous operators, locomotives, and devices, with everything DEJA Cloud has to offer
- 🔄Self-updating via deja update — always on the latest version
macOSLinuxRaspberry Pi
install
bash
$ curl -fsSL https://install.dejajs.com | bash
Downloading DEJA Server v1.2.0...
Installing dependencies...
✓ DEJA Server v1.2.0 installed
→ Starting server...
✓ Server running on ws://localhost:8082
✓ EX-CommandStation connected on /dev/ttyUSB0
→ Signed in · Layout: Pittsburg & Shasta 1:87
deja cli
deja
$ deja start # Start the server
$ deja stop # Stop the server
$ deja restart # Restart the server
$ deja update # Update to latest version
$ deja status # Check server health
$ deja logs # Stream server logs
$ deja init # Re-initialize layout
Cloud App
DEJA.JSCloud
Command central for your layout.
Configure your roster, wire up turnouts and signals, manage devices and connections, and control your layout from anywhere.
- 🗂️Roster Management Add locos with addresses, names, road numbers, and photos — or snap a photo and let AI fill in the details and function mapping
- 🤝Members & Guests Invite co-operators with a shareable link or printable QR code, approve join requests one by one, or let people in the room join instantly with the rotating room code on the Monitor kiosk
- 🔌Device & Connection Management Connect via USB, WebSocket, or MQTT — configure DEJA IO devices or use custom integrations
- 🔀Turnouts & Routes Map physical turnouts and build automated route sequences
- 🚦Signals Configure signal heads and assign them to track blocks
- 🗺️Track Diagrams Draw your layout as a schematic track map — turnouts, routes, and signals stay live and clickable
- 🎆Effects, WLED & Sounds Toggle lights and relays, activate WLED scenes, and play your sound library from any device
- 🖥️DCC Console Send raw DCC-EX commands and view live serial output
☁️
Instant sync across all devices
Change a setting on your desktop — it instantly updates on your phone, tablet, and every connected device.
DEJA IO
Expand your layout. On your terms.
DEJA IO lets you connect common devices — Arduino, Raspberry Pi Pico W, ESP32, or your own custom build — communicating over any supported protocol to expand what your layout can do.
Protocols
MQTTUSB SerialWebSocketWiThrottle
DCC-EX Track Modes
🚂DCC Main⚙️Programming⚡DC / PWM📡Booster
Hardware Devices
🚂
EX-CommandStation
USB Serial
The DCC-EX hardware that drives your track. Connects to the DEJA Server over USB at 115,200 baud.
🔌
Arduino Mega
USB Serial
Connect via USB to DEJA Server for pin-level control of outputs, sensors, and signal heads. WiFi support coming soon.
📡
ESP32
USB SerialMQTT
Connect via USB, or go WiFi-native over MQTT for pin-level control without a cable. WebSocket support coming soon.
📶
Raspberry Pi Pico W
MQTT
WiFi-native CircuitPython device. Connects over your network via MQTT — no USB cable required. WebSocket support coming soon.
💡
WLED
WiFi
Register any WLED controller as a device and trigger its scenes from Throttle, Cloud, or Tour.
Expansion Capabilities
Lights
Sounds
Servos
Sensors
Relays
Signals
Turnouts
Outputs
Guides
Learn DEJA.js
Step-by-step guides to help you get the most out of the platform — whether you're just getting started or expanding a club layout.
🚂
Throttle
Train control, function buttons, consists, and everything you can do from the Throttle app.
📊
Monitor
SoonDiagnostics, DCC command logging, device status, and system health monitoring.
🎟️
Tour
SoonGuest-facing layout tours — interactive effects, media, and area exploration.
Platform
Built for the way you operate.
🤖
AI Roster Enrichment
Snap a photo — AI fills in your roster entry, function mapping and all. Review and accept field-by-field.
☁️
Cloud Sync
Roster, turnouts, and settings sync instantly across all devices through DEJA Cloud.
📱
Any Device
Web app works on phone, tablet, and desktop. PWA install — no app store.
🔒
Private Platform
Subscription-gated access. Your layout data is yours — secured end-to-end by DEJA.js.
⚡
Real-Time
Commands reach your track in under 100ms via WebSocket + serial bridge.
🔧
DCC-EX Native
Built specifically for DCC-EX. Full protocol support — not a general-purpose tool.
🎮
WiThrottle Compatible
Built-in WiThrottle server replaces JMRI for that role. Engine Driver, ThrottleCard, ProtoThrottle, and other WiThrottle clients connect directly — including ThrottleCard’s Apple Watch and game-controller support.
🎆
Effects, WLED & Sounds
Toggle lights and relays, activate WLED scenes, and play your sound library from any device on your network.
📡
MQTT Ready
Optional MQTT broker integration for advanced automation and sensor inputs.
🗺️
Track Diagrams
Drag-and-drop schematic editor — turnouts, routes, and signals, all automated from a clickable track map.
🔀
Multi-Track
Support for Main, Programming, DC/PWM, and Booster modes on separate EX-CommandStations.
🚦
Signal Control
Configure signal heads with full aspect control tied to block occupancy.
Roadmap
In development
WiThrottle supportCloud-hosted monitorVisual Automation BuilderEXRAIL Automation Studio
In progress
Architecture diagramsConnection test flowCloud setup refinementsMulti-device support
Coming soon
📱 iOS Native App🤖 Android Native App🗺️ Layout Map Editor📊 Operations Mode🔔 Push Notifications🔗 Multi-layout Support🤖 AI Conductor
FAQ
Common questions.
Support
Help when you need it.
From our Discord community to hands-on consulting — we've got you covered.
Community (Discord)
Ask questions, share layouts, and connect with other DEJA.js users. Free for all.
AI Chat Support
Coming SoonGet instant answers about setup, configuration, and troubleshooting from our AI assistant.
Support Tickets
Paid plans include support tickets with a guaranteed response time. Priority handling for Engineer and Conductor.
Consulting Services
Per-incident help, prepaid hours, or direct consultation with Track and Trestle Technology for complex layouts and custom integrations.
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DEJA.js is developed by Track and Trestle Technology, LLC
We offer consulting services for DEJA.js projects — big or small. Get in touch →