DAM — Data Access Mediator

The PII firewall for AI agents.

Your data never leaves your machine. The LLM never sees it. Every access is logged.

  "Send the contract to [email protected]        "Send the contract to [email:a3f71bc9]
   and CC [email protected],                       and CC [email:d4f82c19],
   charge card 4111-1111-1111-1111"  ──DAM──►  charge card [cc:b7e31a02]"

        What the user types                       What the LLM sees

DAM sits between your app and the LLM as a local proxy, intercepts PII before it leaves your machine, and replaces it with typed references. Originals stay encrypted in a local vault. When the LLM responds with references, DAM resolves them back — the user sees real data, the LLM never does.

Install

npm install -g @rpblc/dam

Quick Start

# Start the proxy
dam serve
export OPENAI_BASE_URL=http://127.0.0.1:7828/v1
export ANTHROPIC_BASE_URL=http://127.0.0.1:7828

# Or run as a background service (auto-starts on login, restarts on crash)
dam daemon install

No dam init needed — config, vault, and encryption keys are auto-created on first run.

What It Does

| Stage | What happens | |-------|-------------| | Detect | Regex pipeline finds emails, phones, SSNs, credit cards, IPs, IBANs, and 15+ locale-specific patterns | | Encrypt | Each value gets its own AES-256-GCM key (envelope encryption). Master key lives in your OS keychain | | Replace | Values become typed references: [email:a3f71bc9]. The LLM knows the type but never the value | | Resolve | When the LLM responds with references, DAM replaces them with real values before returning to the client | | Audit | Every operation is logged in a SHA-256 hash-chained trail |

Supported Routes

| Route | Format | Default upstream | |-------|--------|-----------------| | POST /v1/messages | Anthropic Messages | https://api.anthropic.com | | POST /v1/chat/completions | OpenAI Chat | https://api.openai.com | | POST /v1/responses | OpenAI Responses | https://api.openai.com | | POST /codex/responses | Codex | https://chatgpt.com/backend-api |

Agent Install (One Command)

npx @rpblc/dam daemon install

Downloads the binary, registers DAM as an OS service, starts it, and verifies health — all in one command. Supports Linux (systemd), macOS (launchd), and Windows (Registry Run key).

CLI

dam serve [--port PORT]              Start HTTP proxy
dam daemon install|start|stop|status Manage background service
dam scan [TEXT]                      Scan text for PII
dam vault list|show|delete           Manage encrypted vault
dam consent grant|revoke|list        Control PII access consent
dam audit [--ref REF]                View audit trail

PII Types

Email, credit card (Luhn), phone, IPv4, date of birth, IBAN, SSN, SIN, postal code, NI number, NHS number, driving licence, INSEE/NIR, tax ID, national ID, VAT number, SWIFT/BIC — plus custom regex patterns via config.

Links

• GitHub
• Full Documentation
• Changelog

License

Apache-2.0