Juan Carlos Valencia

Full-stack multi-tenant platform with schema-per-tenant Postgres isolation, subdomain-based tenant routing and automatic schema provisioning. 17 hexagonal (DDD) modules under strict dependency rules; Go services with Chi (REST) and gRPC for inter-service communication; Next.js 16 App Router frontend on React 19 in a Turborepo monorepo with 5 shared packages. Browser automation via Patchright with anti-detection and fingerprint injection; BullMQ worker pools running 30s scheduled checks through a snapshot → change detection → AI insight → alert pipeline. Elasticsearch search and a LangGraph insight pipeline on Amazon Bedrock (text + vision) exposed through a Django REST Framework API. JWT access/refresh, OAuth 2.0, and a BFF handler for secure cross-subdomain cookie exchange. Deployed on AWS — frontend on Amplify Hosting, four backend services on ECS with Fargate Spot.

Modular NestJS application with 10+ feature modules: authentication, user management, content management, dynamic forms, role management and Google Drive integration. Passport JWT with RBAC and junction tables for fine-grained many-to-many permissions. Hierarchical CMS supporting unlimited nesting via self-referencing parent-child relationships, kept in bidirectional sync with Drive through driveId references. Dynamic forms with configurable fields, validation rules and multi-part uploads via Multer, supporting authenticated and anonymous submissions. Google Drive API v3 with service-account auth and streaming uploads/downloads — metadata in Postgres, files in Drive. Prisma ORM for type-safe queries and migrations, global ValidationPipe with class-validator DTOs, Swagger/OpenAPI docs, and CI/CD to Amazon ECS on Fargate Spot.

Unified TypeScript codebase with platform-specific builds via EAS (dev/preview/production). File-based routing with expo-router and a Guardian component enforcing auth and automatic session restoration. Modular Zustand state architecture across six domain stores, deliberately decoupled from the API layer to prevent circular dependencies. Token-based JWT auth persisted in Expo Secure Store, and an advanced PDF viewer (react-native-pdf) with offline caching. Dynamic form system with a multi-step wizard, validation and file uploads, plus an admin panel with user CRUD and role management.

Participated in the architectural design of a distributed microservices platform with hexagonal architecture and domain-driven boundaries. Event-driven communication over Azure Service Bus and Kafka; MongoDB schemas alongside relational data on Azure SQL with TypeORM. Queue-based microservice for bulk CSV/Excel report generation in Python (pandas), streaming results to the frontend in chunks. Azure AD / MSAL SSO across multiple applications, Elasticsearch search, and a real-time Socket.io microservice. REST and GraphQL APIs with Apollo Server (resolvers, subscriptions), gRPC with protobuf, and Databricks SQL for reporting. React, Vue and TypeScript frontends — one migrated to shadcn/ui. Quality enforced with Jest, TestContainers, SonarQube CI/CD gates at 80%+ coverage and Semantic Release. A high-performance Go microservice (goroutines, channels) ran on AWS Lambda behind API Gateway, with Provisioned Concurrency to minimize cold starts and CloudWatch for latency profiling.

Built full-stack applications integrating React/Next.js with Node/NestJS, using SSR and SSG to improve SEO and bring page load times under 3 seconds. Structured the frontend into Nx microfrontends, documented a component library in Storybook, and added i18next localization for US clients. Replaced Redux with Zustand, managed server state with TanStack Query and SWR, built data grids with TanStack Table, and enforced schema validation with Zod / nestjs-zod. Redis caching cut response times 76% — from 30s to 7s. Designed and optimized Postgres schemas (indexes, partitions, query tuning), ran production deployments on Amazon RDS (RDS Proxy) and EC2, served Next.js apps through CloudFront, and integrated S3, SQS and Lambda. Automated testing with Jest and Cypress sustained 80%+ coverage.

Personal portfolio + engineering blog. Astro SSR public site, Hono RPC API on Bun, React 19 admin SPA with TanStack Router. Powered by Drizzle ORM on Postgres, Valkey caching, isomorphic-dompurify-sanitized MDX, and reduced-motion-safe GSAP timelines.

Designed normalized MySQL schemas with foreign keys and indexing strategies, and implemented the Service and Repository patterns in Laravel. Optimized MySQL with composite/covering indexes, eager loading to fix N+1 queries, and more efficient JOINs. JWT authentication and financial reporting modules covering daily sales, revenue breakdowns and inventory valuation. Vue.js components for inventory, sales and dashboards, deployed on shared hosting.

Designed a QR-based delivery tracking workflow with unique codes per order and implemented the scanning/validation flow in Vue.js. Built secure, high-performance Laravel REST APIs with authentication, role-based middleware, throttling and optimized queries. Integrated geolocation tracking (GPS coordinates in MySQL with timestamps) and tuned Vue.js performance for unstable networks. Monitoring dashboards combined QR validation results with geolocation history for supervisors.