Vault12

Vault12 Zax Cryptographic Relay API

Open-source NaCl-based cryptographic relay operated as asynchronous "dead drops" for end-to-end-encrypted device-to-device communication. Clients establish anonymous session keys via a proof-of-work handshake (POST /start_session, /verify_session) and then post encrypted commands to /command — upload, count, download, messageStatus, delete, plus the Zax 2.0 file-command family (startFileUpload, uploadFileChunk, downloadFileChunk, fileStatus, deleteFile). Vault12 maintains a public test relay with 30-minute message expiration.

GitHub

Documentation

📖
Documentation
https://github.com/vault12/zax
📖
APIReference
https://s3-us-west-1.amazonaws.com/vault12/crypto_relay.pdf

Other Resources

🔗
SourceCode
https://github.com/vault12/zax
🔗
Sandbox
https://zt.vault12.com
🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/vault12/refs/heads/main/apis.yml

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API entry from apis.yml

apis.yml Raw ↑ 
name: Vault12 Zax Cryptographic Relay API
description: Open-source NaCl-based cryptographic relay operated as asynchronous "dead drops" for end-to-end-encrypted
  device-to-device communication. Clients establish anonymous session keys via a proof-of-work handshake
  (POST /start_session, /verify_session) and then post encrypted commands to /command — upload, count,
  download, messageStatus, delete, plus the Zax 2.0 file-command family (startFileUpload, uploadFileChunk,
  downloadFileChunk, fileStatus, deleteFile). Vault12 maintains a public test relay with 30-minute message
  expiration.
humanURL: https://github.com/vault12/zax
baseURL: https://zt.vault12.com
tags:
- Relay
- Cryptography
- Messaging
- File Exchange
properties:
- type: Documentation
  url: https://github.com/vault12/zax
- type: APIReference
  url: https://s3-us-west-1.amazonaws.com/vault12/crypto_relay.pdf
- type: SourceCode
  url: https://github.com/vault12/zax
- type: Sandbox
  url: https://zt.vault12.com