Privacy Policy
Last updated: 19 April 2026
This Privacy Policy explains how Stackd AI collects, uses, and protects your personal information when you use our website (stackdd.tech) and platform (app.stackdd.tech).
Who we are
Stackd AI is a trading name of Certi Technologies Ltd, a company registered in England and Wales. We're the data controller for the information you give us. You can contact us at hello@stackdd.tech.
What we collect
Information you give us directly:
- Your name and email address when you sign up
- Payment details (processed by Stripe — we don't store card numbers)
- Any messages you send us through the enquiry form or by email
- Content you create on the platform (announcement posts, quiz answers, module progress)
Information we collect automatically:
- Pages you visit and how you use the site
- Your approximate location (based on IP)
- Device and browser type
- Session recordings and click behaviour (via PostHog, for improving the product)
Information we don't collect:
- We don't sell your data
- We don't use trackers from ad networks
- We don't run third-party advertising on our platform
How we use your information
We use your information to:
- Give you access to the platform and manage your account
- Take payment and handle billing
- Send service emails (receipts, password resets, important updates)
- Improve the product by understanding how it's used
- Respond when you contact us
- Meet our legal obligations (tax, accounting, fraud prevention)
We don't send marketing emails unless you opt in separately.
Who we share it with
We share data only with services we need to run Stackd AI:
- Supabase — stores your account and platform data
- Stripe — handles payments and subscriptions
- Vercel — hosts our websites
- Resend — sends transactional emails (receipts, password resets)
- PostHog — analytics and session replay on the marketing site
- Upstash — rate limiting on form submissions
- Anthropic — powers the AI Coach (your messages are processed to generate replies, not used to train models)
We don't sell, rent, or trade your data to anyone. We share it only when legally required (e.g. a court order).
How long we keep it
- Account data: for as long as you have an active account, plus 6 years after closure for accounting and legal reasons
- Session recordings: 30 days, then deleted automatically
- Support emails: 2 years
- Payment records: 6 years (HMRC requirement)
If you close your account, we delete your personal data within 30 days unless we need to keep specific items for the legal reasons above.
Your rights
Under UK GDPR you have the right to:
- Access the data we hold about you
- Correct any inaccuracies
- Ask us to delete your data (the "right to be forgotten")
- Export your data in a portable format
- Object to certain processing
- Withdraw consent you previously gave
To exercise any of these, email hello@stackdd.tech. We'll respond within 30 days.
If you're unhappy with how we've handled your data, you can complain to the Information Commissioner's Office (ICO) at ico.org.uk.
Cookies
We use essential cookies to keep you logged in and handle payments. We also use analytics cookies (PostHog) to understand how people use the site. You can disable non-essential cookies in your browser settings — the site will still work but some features may be limited.
International transfers
Some of our service providers (Stripe, Vercel, Anthropic, PostHog) are based in the US or other countries outside the UK. When your data is transferred there, we rely on standard contractual clauses or other legal safeguards approved by the UK government.
Changes to this policy
We'll update this policy if our practices change. The "Last updated" date at the top shows when. Significant changes will be announced via email or a notice on the platform.
Contact
Questions, requests, or concerns?
Email: hello@stackdd.tech
Certi Technologies Ltd, 3rd Floor, 86-90 Paul Street, London, EC2A 4NE. Registered in England and Wales. Stackd AI is a trading name of Certi Technologies Ltd.