Privacy Policy

PLC-Ladder (plcladder.com) is an AI-assisted PLC programming tool: you describe control logic in plain English, and the service drafts IEC 61131-3 Structured Text that is verified by a deterministic compiler and simulator. This policy describes exactly what data the service handles; nothing more is collected than what is listed here.

• Email address: your account identifier, also used for the verification-code email (a 6-digit code you type into the app — no links to click).
• Password: stored only as an argon2 hash. We never store or log the plain-text password.
• Drafting activity: the plain-English queries you submit to the AI drafting feature and the code generated from them, with compile results and timing.
• Auth & security logs: sign-up, sign-in and verification events with IP address and timestamp, kept for abuse prevention and account security. From the IP address we derive an approximate location (country; region and city where the database provides them) using a local IP-geolocation database (IPinfo Lite or GeoLite2) — the address is never sent to a third-party lookup service — and from your browser’s User-Agent header we keep a coarse summary (browser family, operating system, device class). Sign-in events and their metadata are deleted after 90 days; the sign-up record is kept for the life of the account.

• To provide account access and keep your account secure.
• To keep track of your AI credit (the one-time free credit, credit you buy, and what each AI answer used).
• To improve the service. Queries may be reviewed by our team to improve the service.

The site sets a single strictly-necessary session cookie so you stay signed in. There are no advertising cookies, no tracking pixels, and no third-party analytics. That is why you don't see a cookie consent banner: there is nothing optional to consent to.

We use three service providers, strictly to operate the product:

• Anthropic: when you use AI drafting, your query text is sent to the Anthropic API to generate the code.
• Resend: sends the transactional account-verification email (the 6-digit code).
• Amazon Web Services: hosts the application and its database.

We do not sell or share your data for advertising, and no one else receives it.

Your account and drafting history are kept while your account exists. Email support@plcladder.com from your registered address and we will delete your account and its history.

If you start signup but don't verify, we keep your email address so we can help you finish, and we may contact you about PLC-Ladder. Email support@plcladder.com to be removed at any time. Every such email we send tells you how to opt out, and replying STOP is enough.

Questions about this policy: support@plcladder.com. We will update this page if our practices change; the effective date above reflects the latest revision.