Implement data anonymization pipeline for analytics exports

[Smartdevs17]

Context

Analytics exports contain PII (email, name, IP address) which violates data protection regulations when exported for third-party analysis or data sharing.

Current Limitation/Problem

Exports include raw user data. No anonymization or pseudonymization options exist before download.

Expected Outcome

Configurable data anonymization pipeline: strategies (mask, hash, truncate, perturb) applied per field before export, with irreversible anonymization for GDPR-compliant exports.

Acceptance Criteria

• Anonymization strategies: email mask (j***@example.com), name hash (SHA-256 + per-export salt), IP truncation (192.168..), date perturbation (+-3 days uniform)
• Configurable per export type: full (admin only), pseudonymized (analytics team), anonymized (third-party)
• Irreversible guarantee: anonymized exports include no reversible mappings or encryption keys
• Export audit log: record anonymization level, fields transformed, timestamp, requester
• Preview: show anonymized sample rows before export download
• k-anonymity check: warn if fewer than 5 records share identical quasi-identifiers
• Edge case: small dataset (<20 records) -> warn user of re-identification risk before export

Technical Scope

• backend/analytics/domain/anonymization/ - AnonymizationPipeline orchestrator
• backend/analytics/domain/anonymization/ - strategy implementations (MaskStrategy, HashStrategy, TruncateStrategy, PerturbStrategy)
• backend/analytics/controller/ - anonymization configuration API
• backend/analytics/tests/ - k-anonymity validation and re-identification risk tests
• backend/gdpr/ - data classification registry (PII field annotations)

[euniceamoni]

@euniceamoni has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi ,I am a full stack developer and a smart contactor and I would love to work on this issue

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[Delightech28]

@Delightech28 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I'd like to work on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Delightech28 to this issue.

[drips-wave]

Congratulations, @euniceamoni! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

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