Ruben Martinez Tanahara

Technical Lead for a 10-engineer team building cloud-native microservices for an enterprise healthcare logistics platform, using C#, .NET 8/.NET 10, Azure Functions, Durable Functions, SQL Server, and Azure DevOps.

• Lead a 10-engineer team as Technical Lead (promoted May 2026): own architecture decisions, delivery planning, and weekly leadership meetings in a SAFe Agile environment.
• Architected a claims processing platform with Azure AI Document Intelligence (OCR), Durable Functions SLA timers, and a Strategy-pattern reconciliation engine for invoices and receipts; produced six sets of system design diagrams.
• Led the migration of platform services from .NET 8 to .NET 10, resolving NuGet and Central Package Management issues, aligning target frameworks, and repairing Azure DevOps CI/CD pipelines (code coverage, AppScan security scanning).
• Designed the migration from Azure Cache for Redis to Azure Managed Redis and wrote SQL Server provisioning scripts for client integrations.
• Built observability dashboards and alerts in New Relic using KQL and NRQL across environments, improving production monitoring and troubleshooting.
• Authored developer onboarding documentation and standardized CI/CD pipeline templates, using GitHub Copilot and Claude Code workflows to speed up developer ramp-up.

Freelance AI Engineer for a conversational AI assistant embedded in an ERP, serving 100+ users, within a 15-person engineering team.

• Developed the backend of a conversational AI assistant using Google Vertex AI (Gemini) with function calling to query inventory, sales, and collections data in MySQL, returning streamed responses and charts.
• Designed the LLM tool layer and AI orchestration: client-configurable prompts, per-user and per-company access control for every tool, and token-based usage metering for billing.
• Built a RESTful API with .NET 10, C#, and ASP.NET Core minimal APIs (Carter) using Clean Architecture; enforced layer dependencies with NetArchTest architecture tests that fail the build on violations.
• Implemented application security: JWT authentication, role-based access control (RBAC), rate limiting, login brute-force protection, and secrets management with GCP Secret Manager.
• Automated CI/CD with GitHub Actions: build, tests, secret scanning (gitleaks), dynamic application security testing (OWASP ZAP), CalVer releases, and zero-downtime IIS deployments with health checks.
• Built an admin module for user, company, prompt, pricing, usage metering, and account statement management.
• Added per-client time zone support, validated at startup against the MySQL server time zone.

• Developed the mobile e-commerce frontend in Flutter and Dart, with state management in Riverpod.
• Implemented responsive UI layouts from design specifications and integrated REST APIs with Dio.
• Added Stripe payments (Flutter Stripe), secure token storage (Flutter Secure Storage), and cached image loading.
• Delivered assigned modules on schedule in Agile/Scrum sprints and resolved bugs and feature requests with the technical team.