Terms of Service

These Terms of Service (“Terms”) are an agreement between you and Track and Trestle Technology, LLC (“Track & Trestle”, “we”, “us”). They cover DEJA: the Throttle app, this website, the deja command-line tool and server software, device firmware we provide, and any related services (together, “DEJA” or the “Service”).

By creating an account, installing the deja software, or otherwise using DEJA, you agree to these Terms and to our Privacy Policy. If you don't agree, please don't use DEJA.

You need to be at least 13 years old to create an account. If you're under the age of majority where you live, a parent or guardian must agree to these Terms for you. Guests who join a layout with a room code don't create an account; the layout owner who invites them is responsible for their use.

DEJA is model-railroad control software for DCC-EX. The Throttle app and your layout's settings run in the cloud (Google Firebase, hosted on Vercel). The deja server runs on your own computer and talks to your EX-CommandStation and IO devices over USB, your network, MQTT, or WebSocket.

DEJA is free to use. Donations are optional (section 8). Hands-on help is available as paid support sessions from Track & Trestle (section 9). We may add, change, or remove features over time, and we may suspend or discontinue the Service — we'll try to give reasonable notice of anything major.

The deja CLI and server are distributed as compiled software through our installer and GitHub Releases. Subject to these Terms, we grant you a personal, non-exclusive, non-transferable, revocable licence to install and run that software to control your own layouts (including a club layout you help operate).

You agree not to:

• redistribute, sell, rent, sublicense, or publicly host copies of the deja software or the installer;
• reverse engineer, decompile, or disassemble the compiled software, except to the extent the law expressly allows it despite this restriction;
• remove or alter any copyright, licence, or attribution notices;
• use the software to build a competing hosted service.

Device firmware is shipped as source so it can be built on your machine, and it includes third-party code. Third-party and open-source components are licensed under their own terms (see the notices that ship with them), and those terms win for those components. Everything else in DEJA — the software, the apps, the design, and the DEJA name — belongs to Track & Trestle or its licensors, and these Terms don't give you any rights to it except the licence above.

Updates are never installed automatically: you choose when to run deja update. Older versions may stop working with the cloud service over time.

You can sign up with email and password, Google, or GitHub. Keep your sign-in details and any server login tokens (from deja login) secure — anyone holding them can control your layout. You're responsible for what happens under your account, and for the people you add to your layout or give a room code to. Tell us promptly if you think your account has been compromised. You can revoke a connected server from Throttle at any time.

Please use DEJA for running model railroads. Don't:

• break the law, or infringe anyone else’s rights (including copyright in sounds, photos, or videos you upload);
• try to access accounts, layouts, or data that aren’t yours, or probe, scan, or overload our systems;
• get around rate limits, usage limits, security measures, or the review process for shared sounds;
• upload malware, or content that is unlawful, hateful, harassing, sexually explicit, or otherwise inappropriate — guest pages may be seen by children;
• use automated means to scrape the Service or abuse the AI identify feature;
• misuse the public demo layout or harass other users.

“Your content” means the things you put into DEJA: layout configuration, rosters, photos, sounds, videos, guest pages, hunts, automations, and similar. You keep ownership of it. You give us a worldwide, non-exclusive, royalty-free licence to host, store, copy, process, and display your content only as needed to run, secure, and improve DEJA for you — for example, showing your layout to the members and guests you invite.

Uploaded files are public links. Photos, sounds, and guest media are stored at long, unguessable web addresses that aren't private: anyone who has the link can open the file. Don't upload anything you need kept secret.

Sharing sounds. If you submit a sound to the community library, you confirm that you have the right to share it, and you grant every DEJA user a licence to use it in their layouts. Shared sounds are reviewed by Track & Trestle before anyone else can see them, and we may decline or remove any of them. You can un-share or delete a sound at any time; layouts that already use it may keep playing it.

We may remove content or restrict features if we reasonably believe they break these Terms or the law. If you believe something on DEJA infringes your copyright, contact us (section 17) with the details and we'll look into it promptly.

Some features (such as identifying a locomotive or car from a photo) use an AI model. AI suggestions can be wrong. Check them before you rely on them — especially anything about DCC addresses, decoders, or wiring. Suggestions only change your roster when you accept them.

DEJA is free. You can choose to donate to support its development. If you do:

• donations are voluntary and never required to use any part of DEJA;
• you get no goods, services, features, or priority in exchange — a donation is a gift to Track and Trestle Technology, LLC, a for-profit company;
• donations are not charitable contributions and are not tax-deductible;
• donations are non-refundable, except where the law requires otherwise or in the case of a duplicate or mistaken charge — contact us and we’ll sort it out;
• a monthly donation renews each month until you cancel it, which you can do at any time — from your Profile in Throttle if you donated in the app, or from the link in your Stripe receipt email (or by contacting us) if you donated on dejadcc.com; cancelling stops future charges;
• payments are processed by Stripe, and your card details go straight to Stripe — we never see or store them.

Track & Trestle offers paid one-to-one help sessions, booked through our Support page (a Google Calendar booking page). The price, scheduling, and any cancellation terms are shown when you book. Sessions are advice and hands-on help on a best-effort basis: you stay in control of — and responsible for — your layout, wiring, and equipment, and section 10 applies to anything we suggest. Free community help is available on Discord, but it isn't a support channel run by us.

DEJA is provided “as is” and “as available”, without warranties of any kind, whether express, implied, or statutory — including any warranties of merchantability, fitness for a particular purpose, title, non-infringement, and that the service will be uninterrupted, timely, secure, or error-free. Some places don't allow these exclusions, so some of them may not apply to you.

To the fullest extent the law allows, Track & Trestle and its owners, employees, and contractors will not be liable for any indirect, incidental, special, consequential, exemplary, or punitive damages, or for any loss of data, profits, or goodwill, or damage to equipment or property, arising out of or relating to DEJA or these Terms — even if we were told such damages were possible.

Our total liability for all claims relating to DEJA or these Terms is limited to the greater of (a) the amounts you paid us in the 12 months before the event giving rise to the claim, and (b) US$50.

Nothing in these Terms limits liability that can't be limited by law, such as liability for fraud or, where applicable, for death or personal injury caused by negligence.

If someone makes a claim against Track & Trestle because of your content, your use of DEJA in breach of these Terms, or your violation of the law or someone else's rights, you agree to cover our reasonable losses and costs (including reasonable legal fees) arising from that claim. We'll let you know about the claim and give you a reasonable chance to help respond to it.

You can stop using DEJA at any time, and you can ask us to delete your account (see the Privacy Policy). Cancel any monthly donation from your Profile first.

We may suspend or close an account, or revoke the software licence, if you seriously or repeatedly break these Terms, if we must for legal reasons, or to protect other users or our systems. Where it's reasonable, we'll tell you first and give you a chance to fix the problem. Sections that by their nature should survive — including 6, 8, and 10 through 16 — survive after your account ends.

These Terms are governed by the laws of the state in which Track and Trestle Technology, LLC is organized, and by applicable United States federal law, without regard to conflict-of-law rules. Any dispute that can't be resolved informally will be brought in the state or federal courts located in that state, and you and we consent to their jurisdiction. If you live outside the United States, you may also have rights under the laws of your country that these Terms can't take away.

Before filing a claim, please contact us and give us 30 days to try to resolve it informally — most problems can be fixed with a conversation.

We may update these Terms. When we do, we'll change the effective date at the top of this page, and for material changes we'll give notice in Throttle or on this website before they take effect. If you keep using DEJA after the changes take effect, you accept the updated Terms. If you don't agree, stop using DEJA and ask us to delete your account.

DEJA is provided by Track and Trestle Technology, LLC. To reach us, use Send feedback in Throttle (Settings › Get help) or the options on our Support page. Questions about these Terms, your account, or your data are always free — you don't need to book a session.

These Terms and the Privacy Policy are the whole agreement between you and us about DEJA. If any part turns out to be unenforceable, the rest still applies. If we don't enforce something right away, we haven't given up the right to. You can't transfer these Terms to someone else without our consent; we may transfer them as part of a merger, acquisition, or sale of the business.