Part 4 · 2 chapters · ~12 min

Data Privacy, Retention and Deletion (NDPA, GDPR)

Nigeria's Data Protection Act 2023 and the GDPR in engineering terms, lawful bases, data maps, minimisation, retention schedules, deletion across systems (crypto-shredding, backups), data subject requests, breach notification within 72 hours, and cross-border transfers.

8

The law in engineering terms

requirementengineering work
lawful basis and purpose limitationa field inventory: what, why, basis, retention, where stored
data subject rights (access, correction, deletion)an export job and a deletion workflow across services
security of processingencryption, access control, audit logs, testing
breach notificationboth the NDPA and the GDPR set a 72-hour window to notify the regulator (NDPC in Nigeria) after becoming aware
cross-border transfersknow which vendors and regions hold data; adequacy or safeguards
data protection impact assessmentsrequired for high-risk processing (biometrics, credit scoring)

This is engineering guidance, not legal advice: confirm specifics with your data protection officer.

PERSONAL DATA THROUGH ITS LIFE
collect less, keep it for a reason, delete it everywhere
collectminimum needed + lawful basisstoreencrypted, access-loggedusepurpose-limitedretentionscheduled per categorydeleteprimary, replicas, backups, logs, vendors
swipe the figure sideways, or tap expand for full screen
1/4
collect less
Every field needs a purpose and a lawful basis (consent, contract, legal obligation, legitimate interest). Data you never collect cannot leak or need deleting.
minimise at the sourcepurpose + lawful basis per field
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Deleting for real

code
-- crypto-shredding: encrypt each customer's personal fields with a per-customer key;
-- deleting the key makes every copy unreadable, including backups you cannot edit
CREATE TABLE customer_keys (customer_id uuid PRIMARY KEY, wrapped_dek bytea NOT NULL);   -- data key wrapped by KMS
DELETE FROM customer_keys WHERE customer_id = $1;     -- replicas, backups and exports become ciphertext

-- deletion workflow (orchestrated, Workflows P6): each service confirms
-- identity ✔  payments: anonymise (keep ledger rows, legal obligation) ✔  search index ✔  warehouse ✔  email vendor ✔

Ledgers and KYC records usually cannot be deleted while a legal retention duty applies: anonymise or restrict them, and delete when the period ends.