Enterprise Online Secured Payroll Web Application
Automated BIR TRAIN Law & 2025 statutory math engine
Field-level encryption for SSS, PhilHealth, TIN & Bank IDs
Modern decoupled App Router & Pydantic v2 API backend
1-Payslip-per-page print layout & executive summary reports
Multi-tiered statutory compliance, RBAC & immutable audit trails
About the Project
Enterprise Online Secured Payroll Web Application is a full-stack, enterprise-grade payroll system engineered for modern Philippine corporate payroll management. Built using Next.js 14 (App Router, React 18, TypeScript) and FastAPI (Python 3.10+, Pydantic v2), it automates statutory contributions and tax calculations while delivering bank-grade security and print-ready reporting. Key Core System Architecture & Features: 1. Philippine Statutory & BIR Tax Compliance Engine: - BIR TRAIN Law Tax Engine (2023 Revised Schedules): Automatically evaluates semi-monthly (₱10,417), weekly (₱4,808), and daily (₱685) tax-exemption thresholds. - 2025 SSS Contribution Schedule: Supports up to ₱35,000 Monthly Salary Credit (MSC) with exact EE/ER shares. - PhilHealth 5.0% Premium Rate: 50/50 split between employee and employer (₱10,000 floor to ₱100,000 ceiling). - Pag-IBIG Mandatory Contribution: Circular No. 460 standards (₱200/₱200 share). 2. Printable Reports & Payslips: - 1-Payslip-Per-Page Printing: Clean @media print layout featuring company headers, rate basis, itemized earnings/deductions, net pay banner, and employee signature lines. - Location Breakdown Summary: Executive summary metrics and location-level payroll breakdown tables. 3. Bank-Grade Security & Governance: - AES-256 Fernet Encryption: Sensitive employee identification (SSS, PhilHealth, Pag-IBIG, TIN, Bank account numbers) encrypted at rest in the database. - JWT & Role-Based Access Control (RBAC): Protected API endpoints with Admin and Manager permission checks. - Audit Logging: Every sensitive action (logins, payroll locks, profile updates) recorded in an immutable audit trail. 4. Flexible Workflows: - Configurable Weekly Cycles: Custom start and cutoff day configurations (e.g. Wed-Tue) with dynamic live UI updates. - Location Management: Dynamic site assignment with safety guards preventing deletion of active branch locations.
Challenges
Engineered precise floating-point rounding for multi-tiered Philippine statutory compliance (BIR tax schedules, SSS 2025 MSC brackets, PhilHealth 5% ceilings, and Pag-IBIG Circular 460) while maintaining AES-256 field-level encryption for sensitive employee Identifiers without degrading database query performance or report generation speed.
Learnings
Mastered full-stack architecture combining Next.js 14 App Router with FastAPI and Pydantic v2. Gained deep expertise in cryptography (Fernet AES-256 field encryption at rest), statutory payroll math engine design, role-based JWT security, and CSS @media print optimization for single-page corporate payslips.
Development Journey
BIR TRAIN & Statutory Math Calculation Core
Engineered FastAPI tax calculators for BIR TRAIN Law, SSS 2025 MSC brackets, PhilHealth 5% rates, and Pag-IBIG Circular 460.
AES-256 Fernet Encryption & JWT RBAC Auth
Implemented AES-256 field-level encryption for sensitive PII data and JWT authentication with Admin/Manager RBAC scope checks.
App Router Web Client & Glassmorphism System
Constructed responsive dashboards, employee list management, location branch safety controls, and audit trail visualizers.
@media Print Layouts & Railway/Vercel Pipelines
Designed clean 1-payslip-per-page print layouts and deployed backend services to Railway PostgreSQL and web frontend to Vercel.