Privacy & Hashing
HushAsk is built on one guarantee: we cannot tell who sent a message. Here's exactly how that works — technically and in plain English.
The one-sentence version
When you send a message, your Slack user ID is passed through a SHA-256 one-way hash function before anything touches the database. The hash cannot be reversed. The original ID is never stored.
What SHA-256 means in practice
SHA-256 is a cryptographic function that converts any input into a fixed-length string:
- One-way — you can turn a Slack ID into a hash, but you cannot turn the hash back into a Slack ID.
- Deterministic — the same ID always produces the same hash, but only within HushAsk's salted context.
- Collision-resistant — two different IDs will never produce the same hash.
What we store
| Data | Stored? |
|---|---|
| Your Slack user ID | Never — discarded immediately after hashing |
| Your name or email | Never — not requested from Slack's API |
| Your profile photo | Never — not accessed |
Your DM channel ID (source_channel) | Purged — stored temporarily; deleted after the first reply is sent |
| Message content | Yes — for delivery and optional Notion sync |
| User hash (64 characters) | Yes — used only to detect abuse patterns; cannot identify you |
| Target channel ID | Yes — routing only |
| Timestamp | Yes — standard delivery metadata |
The source_channel purge
When you send a message, HushAsk temporarily stores your DM channel ID so it knows where to deliver any admin reply. As soon as a reply is sent — or the conversation is closed without a reply — this value is deleted from the routing table. After that point, there is no record linking the anonymous post to any DM channel.
Can admins see who sent a message?
No. Admins see the anonymous message in their triage channel and can reply — but sender identity is never revealed. The reply is routed through the temporary routing record, which is then purged.
What about Slack itself?
HushAsk can't protect against Slack's own audit logs — that's a Slack platform constraint, not ours. On Enterprise Grid plans, Slack makes bot interaction logs available to workspace administrators. If your company is on Enterprise Grid, your Slack admin could see that you sent a DM to HushAsk — independently of anything HushAsk stores.
To check which plan your company is on: open Slack on the web and go to [yourworkspace].slack.com/account/workspace-settings — the plan is listed under the Overview section. No admin access needed. If it says Enterprise Grid, this caveat applies to you.