Hi, I'm
David Amador

Senior Backend Engineer & Software Architect with over 20 years of solid experience designing and delivering mission-critical distributed microservices, modern PHP 8.5 / Laravel architectures, Docker orchestration, multi-tenant SaaS platforms, and FinTech systems.

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About me

Senior Backend Engineer and Software Architect with 20+ years of experience leading and building mission-critical distributed microservices in multi-tenant SaaS, FinTech, and transactional e-commerce platforms. Specialist in modern PHP 8.5, advanced Laravel ecosystem, reusable internal package design, Docker orchestration, and high-throughput asynchronous processing. Extensive background in service-to-service cryptographic security (HMAC SHA-256 signatures, timestamps), observability and distributed telemetry with Grafana Loki over Spatie Activitylog, and high-volume structured data processing and electronic billing.

Notable Achievements & Core Strengths
  • Distributed Microservices Architecture: Domain-driven decoupling (Auth/Users, Catalog, Payment Processing, Virtual Classrooms, Background Workers) orchestrated via a unified Nginx Reverse Proxy / Gateway.
  • Cryptographic S2S Security: Implementation of secure communication middleware featuring HMAC SHA-256 signatures, timestamp window validation, and secure headers for high-integrity inter-service communication.
  • Electronic Invoicing & Transactional Data Processing: Batch ingestion, schema validation, and processing of structured data packages (JSON/XML), automated payment reconciliation, and strict regulatory compliance.
  • Multi-Tenant Data Persistence: Data isolation strategies (Shared Database vs. Database-per-Service), continuous relational migrations in MySQL 8.2, and query optimization for high performance.
  • Internal Core Libraries & SDKs: Creation and maintenance of corporate Composer packages standardizing token authentication with Sanctum, structured JSON responses, and granular roles and permissions.
  • Asynchronous Processing & Docker: Background worker execution in Laravel (queue:work), scheduled cron jobs (schedule:work), containerized environments with Docker Compose, and source control via Git and Azure DevOps.
Architectural Philosophy & Software Quality

My approach combines robust engineering principles (Clean Architecture, SOLID, DRY, KISS) with pragmatic business alignment. I focus on delivering resilient, highly secure, auditable, and testable systems that scale smoothly alongside enterprise growth without accumulating unnecessary technical debt.

Work Experience

Kilopolis
Founder & Lead Software Architect / Senior Backend Engineer
Multi-Tenant SaaS Platform Modular Microservices Architecture PHP 8.5 · Laravel · Docker · MySQL 8.2

Led the end-to-end architectural design, backend engineering, and containerized deployment of the Kilopolis SaaS platform, building high-criticality distributed services, cryptographic inter-service security, and asynchronous background processing:

  • Distributed Architecture & Microservices: Decoupled business domains (Auth/Users, Catalog, Payment Processing, Virtual Classrooms, and Background Workers) unified under an Nginx Reverse Proxy / Gateway.
  • Advanced Laravel (v11 / v12) & Core Packages: Distributed Sanctum token introspection middlewares, RBAC authorization policies (granular Roles and Permissions), Form Requests, advanced Eloquent, complex polymorphic relationships, and structured API responses.
  • Observability & Telemetry: Distributed log integration with Grafana Loki over Spatie Activitylog for centralized event traceability and auditing.
  • Cryptographic Inter-Service Security (S2S): Implemented secure inter-service communication protocols using HMAC SHA-256 signatures, timestamp validity windows, and tamper-proof headers.
  • Hybrid Multi-Tenant Persistence: Tenant-isolated database architecture, structured relational migrations in MySQL 8.2, and high-performance query optimization.
  • Asynchronous Processing Engine: Implemented asynchronous background queues in Laravel (queue:work), scheduled cron tasks (schedule:work), and reliable synchronization without overlaps.
  • Transactional Payments & Automated Invoicing: Full integration with Bold Colombia payment gateway, automated subscription billing, payment reconciliation, and electronic invoicing workflows.
  • Docker Infrastructure & Repositories: Containerized development and production environments using Docker and Docker Compose on Alpine Linux, managing code repositories with Git and Azure DevOps.
Publicis Groupe
Senior Backend Developer
Global Advertising & Tech Laravel · Drupal · WordPress

Developed standardized micro-backends in Laravel for enterprise internal projects. Designed complex taxonomies and content structures in Drupal for human resources and showcase portals. Advanced web performance optimization and redesign.

Flores a Colombia, Inc. (daFlores / Roses and Boxes)
Senior E-commerce & Web Developer
High-Traffic International E-Commerce Logistics & Payment Gateways

Full-stack engineering and lifecycle management for high-traffic international e-commerce storefronts (daFlores, Roses and Boxes, Florerías Latinas). Engineered core administrative modules for sales orders, accounts receivable, real-time inventory management, international courier integrations, and automated financial reporting.

Delaware
Senior Backend Consultant
PHP & Enterprise Oracle Clients: Bogotá Chamber of Commerce & Claro Colombia

Built and maintained high-availability enterprise web applications for Bogotá Chamber of Commerce and telecommunications leader Claro Colombia, integrating mission-critical Oracle databases.

TotalCode Software
Senior Software Engineer
Enterprise ERP EDI Messaging · UPS & FedEx Logistics

Engineered comprehensive web ERP in PHP and MySQL managing purchasing, sales, inventory auditing, invoicing, EDI messaging protocols, barcode generation, bills of lading, and automated shipping tracking integrations with UPS and FedEx.

Technical Competencies & Skills

Architecture & Distributed Systems
  • Microservices Architecture: Domain-driven decoupling orchestrated via an Nginx API Gateway.
  • Cryptographic S2S Security: HMAC SHA-256 signatures, timestamp validation, and request integrity protection.
  • Persistence Strategies: Hybrid architectures (Shared Database vs. Database-per-Service / Multi-Tenant).
  • Internal Composer Packages: Corporate SDK design and versioning of reusable libraries.
  • Design Principles: Clean Architecture, SOLID, DDD, KISS, DRY, High Cohesion & Low Coupling.
Backend & PHP / Laravel Ecosystem
  • Modern PHP 8.5: Strict typing, native Enums, match expressions, attributes, and constructor promotion.
  • Advanced Laravel (v11 / v12): Distributed Sanctum token introspection middlewares, RBAC authorization policies (granular Roles & Permissions), Form Requests, advanced Eloquent, and complex polymorphic relationships.
  • Asynchronous Processing: Background queue workers (queue:work), cron task scheduling, and background jobs.
  • Eloquent & Optimization: Polymorphic relationships, eager loading, and N+1 query elimination.
  • APIs & Web Services: Clean RESTful endpoint architecture, JSON data serialization, and third-party API integration.
SaaS, FinTech & Transactional Platforms
  • Electronic Invoicing & Data Processing: Batch ingestion, schema validation, and processing of structured packages (JSON/XML).
  • Transactional Reconciliation & Auditing: Automated payment reconciliation, fee settlement, and business rules engine.
  • Multi-Tenant Architectures: Tenant database isolation, dynamic tenant provisioning, and centralized relational schema management.
  • Transactional Payment Gateways: Bold Colombia, Stripe, PayPal, PayU, and MercadoPago.
  • API Interoperability: Secure RESTful API integrations with enterprise, banking, and government endpoints.
Infrastructure, DevOps & Cloud
  • Docker & Docker Compose: Multi-container environments on Alpine Linux, Docker Compose orchestration, and reproducible services.
  • Nginx Gateway: Reverse proxy, load balancing, FastCGI routing, and SSL termination.
  • AWS Cloud: Secure storage with S3 (Flysystem), Amazon CloudFront (CDN), and EC2 compute.
  • Version Control & Repositories: Source code management with Git, repositories in Azure DevOps and GitHub, and private Composer packages via SSH.
  • Operating Systems: Linux (Ubuntu/Debian/Alpine), macOS, Windows, and enterprise server management.
Databases & Persistence
  • MySQL 8.2: Complex relational modeling, structured schema migrations, and Soft Delete auditing.
  • Relational Engines: PostgreSQL, Oracle Database, SQLite.
  • Performance Optimization: Composite indexing, EXPLAIN execution analysis, locking prevention, and referential integrity.
  • Caching & Throughput: Redis, distributed session handling, and latency minimization.
Auditing, Quality & Frontend
  • Observability & Telemetry: Distributed log integration with Grafana Loki over Spatie Activitylog and mission-critical operational traceability.
  • Testing & Quality: Unit, Integration, and End-to-End testing suites (PHPUnit, Pest).
  • Modern Frontend: HTML5, CSS3, JavaScript ES6+, Bootstrap 5, TailwindCSS, Vue.js, and jQuery.
  • Payment Gateways: Bold Colombia, Stripe, PayPal, PayU, and MercadoPago.

Training & Continuous Learning

Microservices Architecture & Distributed Systems

Specialization in decoupled microservices architecture, cryptographic service-to-service security (HMAC SHA-256 signatures), hybrid persistence strategies, modular services, and high-concurrency systems.

PHP 8.5 & Advanced Laravel Ecosystem

Corporate Composer packages & internal SDK design, advanced middlewares, token authentication with Sanctum, asynchronous background jobs, and OWASP security best practices.

DevOps, Containers & Cloud

Containerization with Docker on Alpine Linux, Docker Compose orchestration, Nginx Reverse Proxy / FastCGI tuning, AWS S3 / CloudFront, and repository management with Git and Azure DevOps.

Transactional Systems & Electronic Billing

Electronic billing, batch ingestion of structured data packages (JSON/XML), automated payment reconciliation, API security, and interoperability standards.

Languages

Spanish: Native · English: B1 (Conversational proficiency, professional communication, and technical documentation).