Engineering & Cryptography
In-depth technical papers on phone number entropy, financial audit reconciliation, and sub-millisecond distributed lookup architecture.
Processing 50,000 Hashes in 40 Seconds - Memory-Mapped IO and Sharded Queues
An engineering deep dive into the high-throughput architecture, binary chunk serialization, and distributed job orchestration powering LOOKUP API's 50,000-item batch engine.
Handling Dropped Safaricom Daraja STK Push Callbacks - An Idempotent Reconciliation Architecture
A production architecture guide for African fintechs to handle dropped or delayed M-Pesa STK push callbacks, resolve ledger state mismatches, and automate payment verification.
Salting Is Not Enough - Why You Need HMAC-SHA256 with KMS Secrets for Mobile PII
A cryptographic teardown explaining why static salting fails to protect phone numbers against modern GPU clusters, and how security engineers implement HSM/KMS-backed HMAC-SHA256.
Architecting a 100M-Record Sub-Millisecond Reverse Lookup Engine with Zero Cold Starts
A technical breakdown of the distributed architecture, partitioning topology, memory indexes, and sliding-window rate limiters behind LOOKUP API.
Resolving M-Pesa & Payment Audit Log Mismatches Using SHA-256 Reverse Ingestion
How African fintech engineering teams resolve transaction ledger mismatches and audit failures when upstream providers or security policies only retain hashed mobile identifiers.
Why Unsalted SHA-256 Does Not Anonymize Phone Numbers - The 25.5-Bit Entropy Problem
A mathematical and empirical analysis demonstrating why unsalted SHA-256 hashes of Kenyan mobile phone numbers offer zero cryptographic anonymity.