This describes what MAAC Go Email actually stores and who touches it. It is written from the running system rather than from a template, so it is specific — and it will be updated when the system changes.
Last updated 18 October 2026 · Operated by Crescendo Lab (漸強實驗室)
You are our customer: you sign in and send email. The people on your contact list are your recipients — we process their data on your instructions, as a service provider. You decide who is on your list and what you send them; you are responsible for having permission to contact them.
We do not inject tracking pixels or rewrite links ourselves. Open and click data reaches us from our mail delivery provider (Resend), which performs that measurement as part of delivering the message, and reports it back to us by webhook. If you would rather your recipients were not measured this way, that is a provider-level setting and you should contact us before sending.
The public pages and signed-in product use Google Analytics 4 to count visits, sign-ups and privacy-safe feature usage. Its advertising features are switched off: no Google signals, no ad personalisation, no advertising pixels and no session recording. We do not send account IDs, email addresses, contact-list content, campaign content or URL query strings to Google Analytics. Google Analytics sets its own cookies (_ga, _ga_*). We also set:
edm_attr — a first-party cookie recording where you arrived from, kept 90 days, so we can tell a real visitor from our own team reloading the page. It contains campaign parameters and the referring site, never your identity.| Processor | What for | What they see |
|---|---|---|
| Resend | Delivering email | Recipient addresses, subject and body of messages you send, delivery and engagement events |
| Google Cloud | Hosting, database, image storage | Everything above, at rest. Application and database run in asia-east1 (Taiwan) |
| Google Analytics | Visits, sign-ups and privacy-safe product feature usage | Pages viewed, feature names, approximate location, device and browser type. No account IDs, email addresses, contacts or campaign content |
| Google Identity | "Continue with Google" sign-in | Your email address and name, if you choose that sign-in method |
| Stripe | Prepaid credit top-ups | Your payment details, directly — they never pass through us |
| Slack | Our internal signup notifications | Your account email and sign-in method |
Images you upload for your emails are stored in a Google Cloud bucket and served from a public, unguessable URL — mail clients fetch images anonymously, so they cannot be access-controlled. Do not put anything confidential in an email image.
Contacts, campaigns and delivery records are kept for as long as your account exists, because they are the record of what you sent. Login codes are deleted a day after they expire. Suppression entries are kept deliberately — deleting them would let a previously unsubscribed person be mailed again.
You can delete individual contacts and campaigns yourself in the app. To delete your whole account and everything in it, email info@cresclab.com from your account address; we remove the account, its contacts, campaigns, delivery records and uploaded images.
If you are a recipient rather than a customer: the sender controls your data. Every campaign carries a one-click unsubscribe link, which stops that sender from mailing you immediately. For anything else, contact the sender directly — or us, and we will pass it on.
Traffic is HTTPS only. Sessions are signed tokens. API keys are stored as bcrypt hashes behind a short lookup prefix, so a database dump does not yield working keys. Secrets live in Google Secret Manager, not in code.
Crescendo Lab (漸強實驗室) — info@cresclab.com · cresclab.com