In enterprise software delivery (especially banking, healthcare, and global SaaS), Personally Identifiable Information (PII) protection is a non-negotiable security requirement:

Plaintext Logging: Developers casually logging raw phone numbers or national IDs, leaking PII to centralized Elasticsearch/Datadog clusters;
Unredacted UI Responses: Unprivileged support operators viewing unmasked customer credit card numbers.

BitzOrcas.Modern includes an embedded IDataMasker engine and [Masked] contract attributes: Dynamically masking sensitive values during JSON serialization, logging, and audit persistence.

Data Masking Lifecycle and PII Defense

Step 1: Declaring Masked Fields on Contracts

Annotate sensitive fields with [Masked]:

using BitzOrcas.Application.Abstractions.Security;

namespace BitzOrcas.Identity.Contracts.Dtos;

public sealed record UserProfileDto
{
    public string UserId { get; init; } = string.Empty;
    public string FullName { get; init; } = string.Empty;

    // Phone masking: preserves first 3 and last 4 digits (e.g. 138****5678)
    [Masked(MaskType.PhoneNumber)]
    public string PhoneNumber { get; init; } = string.Empty;

    // Email masking: preserves prefix and domain (e.g. a***z@corp.com)
    [Masked(MaskType.Email)]
    public string Email { get; init; } = string.Empty;
}

Step 2: Sanitizing Audit Entries via IDataMasker

using BitzOrcas.Application.Abstractions.Security;

public static class AuditLoggingExtensions
{
    public static string ToSafeLogString(this string rawPhone, IDataMasker masker)
    {
        // 1. In-memory masking with minimal heap allocation
        var masked = masker.MaskPhoneNumber(rawPhone);

        // 2. Return sanitized string safe for centralized logging
        return masked;
    }
}

Summary

IDataMasker fortifies platform privacy:

Declarative Attributes: Clean, readable property annotations;
Zero PII Leaks: Sanitized logs, traces, and external APIs by default;
Audit-Ready Compliance: Meets strict GDPR and financial security audits out of the box.