Great on Find Indices of Two Numbers That Add Up to Target, Difficulty Easy
Great on Design a Scalable and Compliant SaaS Platform Architecture, Difficulty Hard
Great on Enhance Kubernetes Security on GCP, Difficulty Easy
Architected and deployed scalable ELT pipelines using BigQuery and Airflow
Presented architectural roadmaps to executive leadership
Optimized SQL query performance and storage schemas
Acted as a technical consultant for Product teams
Designed and implemented a PII anonymization framework
Led high-level engagements with local partners and stakeholders
Conducted market research and technical discovery sessions
Bridged the gap between technical AI tools and end-user requirements
Developed real-time analytics dashboards for clients
Recommended and implemented industry best practices for data modelling
Developed scalable data pipelines to support real-time analytics and reporting
Leading a community of developers
Organising technical workshops
Advocating for Google Cloud adoption in the region
Mentored 50+ developers on GCP architecture
A full-stack reconciliation platform built to automate the matching of vendor transaction files against core transaction data. The platform provides a guided 4-step vendor onboarding wizard with intelligent column field mapping, configurable subtype detection rules (keyword/prefix/suffix matching with AND conditions), and automated reconciliation scheduling via Cloud Run. Key features include: multi-file reconciliation (transaction + reversal files with cross-file matching), two-pass reconciliation using primary and fallback matching references, balance anchors for running balance tracking, a readjustment approval workflow, EMTL/IBT/card payment subtype support, upload detail drawers with skipped record visibility, a reconciliation health report pivot grid, and role-based access control. Tech stack: React, TypeScript, Tailwind CSS, Vite, Supabase (auth + DB), BigQuery, Python (Cloud Run backend), Google Cloud Storage.
Designed and maintained the dbt transformation layer for core transaction data across Nigeria and DRC (Democratic Republic of Congo) markets. Built and iterated on models covering daily transaction replicas for corporate and personal wallets, EMTL charge extraction, user loan eligibility scoring, savings plan views, pybot (receipt) orders and accounts, transaction segmentation by type, unified loan models, smart save transactions, and AUM (Assets Under Management) models for the DRC market. Also maintained data quality guardrails — including NULLIF guards for division-by-zero, deduplication of loan statuses, and refactoring of weekly source models. Tech stack: dbt, BigQuery, SQL, Python.
Built and maintained real-time change stream pipelines that capture MongoDB document changes and stream them into Google Cloud Spanner and BigQuery. Extended the pipeline to cover the Nigeria staging environment (ng_staging) and wallet transactions. Hardened the pipeline for production reliability by handling invalid UTF-8 bytes in BSON strings with silent replacement logging and resilient iterator restart logic. Tech stack: Python, MongoDB Change Streams, Google Cloud Spanner, BigQuery, Cloud Run.
Improved the account statement generator service to correctly handle non-NGN transactions (USD, CDF, CAD, EUR, GBP) from international markets. Non-NGN transactions arrive without a linked transaction document, previously causing narrations to show as raw type names (e.g. "Fx Tx Dr", "Wallet Topup"). Built structured narration logic for wallet_topup, fx_tx_dr, p2p, and transfer types using available meta fields (sender_name, recipient_name, narration, RRN), with CREDIT/DEBIT-aware name display. Tech stack: Python, Google Cloud Run, Jinja2, WeasyPrint, GCS.

Mustapha A. is mid-senior Level Developer