Subsystems and rewrites,
not patches.

Decommissioned a legacy XMLRPC / TGScheduler jobserver and migrated the platform onto a managed Celery framework I designed end-to-end. +10,787 LOC across 42 files, multi-tenant context restoration, 50+ legacy jobs ported. Runtime owner two years post-launch.

Ten-month, eight-version rewrite of the platform's core checkout-status workflow — the surface that touches every customer transaction. Python / SQLObject backend, ExtJS + Angular UI, SQL migrations and trigger logic. Persistence and tolerance for rework until it landed cleanly.

Two compounding bugs causing endless loads — missing SQL pagination on grouped queries plus inverted slicing in ReportJob. Real query-layer surgery, not a UI band-aid: P95 from 15.4 s to 0.67 s. Three rewrites before landing — quality over speed.

Dangling-IP subdomain takeover; CSRF tokens issued from a predictable Mersenne-Twister PRNG with state recovery through a 27-file import footprint; unauthenticated callback enabling SMS-MFA bypass and account takeover; leaked-credential audit. Each in executive register, with ISO 27001 framing and remediation plans.

Authored a Claude Code slash-command suite now in production use by the team; built an MCP-driven multi-source evidence pipeline; quantitative analysis of a 1,000-MR review corpus with a pre-merge tooling proposal that automates ~1/6 of recurring review feedback.

Unilateral design-system rollout touching email, web app and login. New unified styles, redesigned login, asset refresh and template updates. Frontend ownership on top of the backend reputation.

Co-founded and led an AI-powered city-traffic-optimisation startup. Distributed simulation platform processing 3M+ data points across 140 simulated years on Google Cloud 96-core instances. ML-accelerated optimisation, matrix-based safety calculations, 16 intersections deployed across three municipalities.

Python data-management platform for WHO; UNICEF frontend reliability for a global user base; 1.5M-word content-management system; data-enrichment pipeline for 20,000+ medical clinics via Scrapy; OpenAI-powered content strategy with automated A/B testing — pre-ChatGPT, 2021–22.