From support desk to systems architect — I build software that survives real users.

An internal enterprise platform for a Philippine company, designed and built from zero. Thirty-five functional modules are kept coherent by a single multi-stage workflow engine: approval delegation, stage-gated edit permissions, rejection history, bulk operations across fifteen-plus form types. SAP Business One integration carries a request all the way to ERP posting — payment drafts and purchase orders created automatically. Sentry tracing, branded transactional email, generated PDF certificates: production, not prototype.

• TypeScript ·
• Prisma ·
• SAP B1 Service Layer ·
• Sentry ·
• Nodemailer ·
• pdf-lib

Built for a real live event with a fixed, immovable deadline. Real-time attendance tracking, QR-based pledges, and a category-aware raffle engine with winner exclusion and grand-raffle logic — twenty-three API endpoints holding up while the room was full and there was no retry button.

• Real-time attendance ·
• QR pledges ·
• Raffle engine ·
• 23 API endpoints

A multi-tenant HRIS built as SaaS from the start. Billing — organizations, invoices, subscriptions, audit logs — lives in its own schema, fully isolated from tenant data: employees, departments, positions, salary history. The schema-per-tenant trade-offs made deliberately, with audit logging across the boundary.

• Schema-per-tenant ·
• Billing & subscriptions ·
• Audit logging ·
• Data isolation