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phileas-dotnet

phileas-dotnet is a .NET library for detecting and filtering Personally Identifiable Information (PII) from text. It provides a flexible policy-driven approach to redacting, masking, replacing, or encrypting sensitive data such as SSNs, email addresses, phone numbers, credit card numbers, and more.

Features

  • A comprehensive set of built-in PII identifiers covering SSN, ITIN, Canadian SIN, email, phone, credit card, IP, URL, date, ZIP, street address, names, locations, hospitals, custom dictionaries, custom regex identifiers, sections, and more
  • AI-powered entity detection through the PhEye filter, backed by a remote NER service
  • Multiple filter strategies, including redact, mask, hash, encrypt (AES-GCM / FF3-1 format-preserving), realistic random replacement, static replacement, and others
  • Policy-driven configuration that defines what to detect and how to replace it using plain C# objects, JSON, or PhiSQL
  • Referential integrity through the opt-in CONTEXT replacement scope, which keeps random replacements consistent across documents
  • Span disambiguation that resolves competing classifications of the same text by surrounding context
  • PDF redaction that detects and redacts PII in PDFs, rasterizing pages so no text is recoverable
  • Word & Excel redaction that detects and redacts PII in .docx/.xlsx documents in place (.NET port only)
  • An optional cross-platform REST service (Phileas.Rest) for filtering text and documents, with MongoDB-backed policy/context management and OCR
  • Extensibility through IContextService, which lets you persist replacement mappings in any store (Redis, database, etc.)

Project

The Phileas library (NuGet package: Phileas) contains all filter types, policy configuration, and the FilterService entry point.

Quick Example

using Phileas.Policy;
using Phileas.Policy.Filters;
using Phileas.Services;

var policy = new Policy
{
    Name = "my-policy",
    Identifiers = new Identifiers
    {
        Ssn = new Ssn(),
        EmailAddress = new EmailAddress()
    }
};

var result = new FilterService().Filter(policy, context: "default", piece: 0,
    input: "Patient SSN 123-45-6789, contact admin@example.com");

Console.WriteLine(result.FilteredText);
// Patient SSN {{{REDACTED-ssn}}}, contact {{{REDACTED-email-address}}}

Next Steps