Laravel | Flutter | Production Systems

I architect and maintain systems handling financial transactions, field operations, and multi-tenant workflows for thousands of active users.

Backend (Laravel/PHP)

• Multi-tenant architecture with dynamic database connections per tenant
• Approval workflow engine with state machines and authority-based routing
• Financial transaction processing with ACID compliance and audit trails
• Query optimization: eager loading, index design, N+1 elimination
• Firebase Cloud Messaging integration for real-time notifications
• Payment gateway integrations (Flutterwave/Paystack) with webhook handling
• Granular RBAC with route-level permissions and middleware chains
• Schema design: composite keys, foreign key constraints, soft deletes, JSON columns

Mobile (Flutter/Dart)

• Cross-platform apps (iOS/Android) with 5K+ active installations
• Riverpod for state management with provider composition
• Offline-first: local SQLite cache with background sync
• WebView integration for OAuth flows and payment processing
• FCM push notifications with background message handling
• PDF generation from widgets, screenshot capture, Share API integration
• Service layer pattern with proper error propagation and retry logic

Architecture

• Multi-tenant SaaS with tenant isolation at database and cache layers
• Event-driven workflows with before/after snapshots for rollback
• Automated billing cycles with proration and reconciliation
• Document generation pipeline (bills, receipts, statements)
• Job queue processing with failed job handling and retry strategies

Systems I've built serve municipal waste service operations across multiple locations:

• Payment processing with transaction verification and balance tracking
• Multi-level approval workflows with authority delegation
• Automated monthly billing cycles with proration logic
• Mobile field apps with offline operation and sync
• Job scheduling with GPS tracking and photo evidence
• Real-time push notifications for payment confirmations
• Export pipelines for financial reporting and analytics

These systems process real transactions where data integrity and uptime are critical.

Backend: PHP 8+, Laravel 10+, MySQL 8+, Eloquent ORM, Firebase Admin SDK, Guzzle
Mobile: Flutter 3+, Dart 3+, Riverpod, FCM, WebView, PDF/Image libraries
Tools: Git, Composer, VS Code, Postman, MySQL Workbench
Patterns: Multi-tenancy, Service Layer, Repository, Factory, Observer, DI

Data Integrity First
Database transactions, foreign key constraints, before/after snapshots, comprehensive audit trails.

Performance at Scale
Eager loading, proper indexing, query analysis, caching strategies, background job processing.

Defensive Programming
Authorization checks at every layer, input validation, SQL injection prevention, graceful error handling.

Maintainable Code
Clear naming, logical abstractions, inline documentation for complex logic, migration rollback plans.

Real-World UX
Offline capability, poor network handling, immediate feedback, no silent failures.

Pre-Development
Map business workflows, design state machines, define database schema, document API contracts.

During Development
Test financial paths thoroughly, wrap critical operations in transactions, log strategically, optimize queries early.

Deployment
Verify backups, stage rollouts, monitor error rates, profile performance, iterate based on metrics.

Event-driven microservices, Laravel queue optimization, Flutter performance profiling, database sharding.

Looking for roles involving:

• Backend systems requiring scale and complexity
• Mobile apps with real business impact
• Teams that prioritize reliability and code quality
• Technical challenges with measurable outcomes

Contact: Available via GitHub or LinkedIn.

Production systems engineer. I build things that work.