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Kastro Labs → free community tool

Use AI. Share with care.

DMZ is a free community project by Kastro, providing the DMZ Chromium extension. Portal and Gateway are deferred. Download the alpha ZIP and find installation guidance and voluntary feedback at dmz.is. Optional Kastro assistance is separate.

Visit dmz.is ↗See how ↓

DMZ attempts to mask selected identifiers on your device and restore unchanged reply markers locally. No DMZ account, subscription or seat minimum. The AI page can see the original draft before masking; failures warn and continue, and attachments are sent unchanged.

dmz.is · Free community project · previewA free community project by Kastro

// How it works

Detect. Mask. Restore.

Staff keep using their AI tools. dmz is designed to keep selected direct identifiers out of the prompt.

DMZ · synthetic dataOn device
01 · You writeOn device

Draft a reply for Arna Jónsdóttir, ID 140182-8858. Send to [email protected].

Illustration of planned behaviour. All values are synthetic; test ID numbers use century digit 8.
  1. 01

    Detect

    We look for direct identifiers in the text before it is sent. The preview covers a limited set, and reviewed measurements show where it misses.

  2. 02

    Mask

    Each identifier gets a visible, unique token. An ID number becomes ⟦KT-1⟧.

  3. 03

    Restore

    When unchanged tokens come back, the real value is restored on the device. Restoration requires the marker to remain unchanged.

// Phase one detection

Icelandic matters.

Icelandic names and ID numbers do not follow English patterns. dmz is built for Icelandic, with declension handling on the roadmap.

Example of planned declension handling; not a claim about current accuracy.
CaseReal valueTo model
nom.GuðrúnXXXXXX
acc.GuðrúnuXXXXXXX
dat.GuðrúnuXXXXXXX
gen.GuðrúnarXXXXXXXX
Kennitala (ID)
Date and century digit; check digit
Icelandic names
Basic and trained previews differ; some forms are missed
IS IBAN
26 characters; mod-97 check
Payment cards
13–19 digits; Luhn check
Phone numbers
+354 or local seven digits
Secrets
Keys, JWTs, bearer tokens, connection strings

Direct identifiers only. Context can still identify people.

// Free community tool

DMZ first. Built with feedback.

Explore local masking, measured limits and ways to help. Portal and Gateway are deferred without a delivery commitment.

01Free preview

DMZ Chromium extension

Supported browser chats

Best-effort local masking and restoration. Read the installation status and warnings before testing with fabricated data.

Where real values liveOn the user’s device
02Development evidence

Measurements

Understand coverage

Reviewed summaries show progress and misses. Independent validation remains incomplete.

Where real values liveNo prompt collection
03Voluntary feedback

Community

Help improve the tool

Fabricated examples, compatibility reports and translations. No purchase or account required.

Where real values liveSynthetic reports only

// Know the limits

Precise words. On purpose.

Security claims should be backed by data. Explore the prototype’s limits and benchmarks on dmz.is.

See the data boundaries ↗
We sayWe don’t say
DMZ masks selected direct identifiers on the deviceAnonymous text
Free DMZ use, with no DMZ accountA general store release
We measure accuracy per identifier type100% detection
Original drafts are visible to the AI page before maskingFull legal compliance

Everything about dmz

dmz.is ↗

Free preview, installation, limits and community feedback at dmz.is. Code licensing remains undecided.