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Alejandro Jimenez Diaz

Full Stack Developer

Profile

Full Stack Developer building production software end to end — backend, frontend, mobile, infrastructure and AI. Currently shipping a multi-tenant AI conversational platform with self-hosted voice, RAG pipeline and hexagonal architecture. Background in nautical engineering: 8 years managing complex systems where failure was not an option.

Experience

Full Stack DeveloperKamaleonte SL
San Fernando, Spain · Full-time
  • Architected and built a multi-tenant AI conversational platform from scratch — hexagonal architecture, RAG pipeline with Qdrant, multi-channel (voice, WhatsApp, web, kiosk) with full workspace isolation.
  • Built self-hosted voice infrastructure: real-time STT/TTS streaming, session state machine with data collection, human transfer and silence detection. SIP trunking for production phone calls.
  • Ship complete products end to end: backend APIs (FastAPI, Node.js), web dashboards (Next.js), mobile apps (Flutter), CI/CD pipelines and Docker-based deployments to dedicated servers.
  • Manage infrastructure: two Hetzner servers, automated deployments via GitHub Actions, security hardening (iptables, fail2ban, SSH key-only, HMAC webhook verification).
Multiplatform App DeveloperKamaleonte SL
San Fernando, Spain · Training contract
  • Built mobile apps with Flutter and .NET MAUI — published to both App Store and Google Play with payment integration (Adyen), video processing and NFC.
  • Developed backend services with Node.js and C#/.NET for workforce management, loyalty programs and document ingestion systems.
Full Stack DeveloperXerintel Internet Technologies SL
Jerez de la Frontera, Spain · Internship
  • Developed web applications with Angular and PHP. REST API integrations and relational database management.
Chief EngineerNaval Sector
Spain · Full-time
  • Managed mechanical, electrical and hydraulic systems on vessels. Diagnostics and repairs under pressure with zero margin for error.

Selected Projects

AI Conversational PlatformMulti-tenant SaaS for deploying AI agents across voice, WhatsApp, web and kiosks. Self-hosted voice with RAG pipeline, admin panel and analytics.
Python · FastAPI · Next.js · PostgreSQL · Qdrant · Redis · Docker · CI/CD
Document Ingestion PlatformMulti-channel document processing (chatbot, WhatsApp, VoIP) with custom voice server and unified pipeline.
Node.js · TypeScript · VoIP · WhatsApp API · WebSockets · PostgreSQL
Interactive Screen AppConsumer app for sharing media on giant screens at events. Published on iOS and Android with real-time content moderation.
Flutter · Firebase · Adyen · Video Processing
Workforce Management PlatformMobile app + admin panel for shift management, NFC clock-in, GPS tracking and automated compliance reporting.
React · Laravel · PHP · NFC · MySQL
Regatta Navigation AppSole developer. Calculates buoy positions from wind data with sub-meter GPS precision. Replaced a manual process.
Ionic · Spring Boot · Java · GPS · PostgreSQL

Skills

LanguagesTypeScript, Python, C#, Java, Dart, PHP, SQL
BackendFastAPI, Node.js, Express, .NET, Spring Boot, Laravel, GraphQL
FrontendReact, Next.js, Angular, Tailwind CSS
MobileFlutter, Ionic, .NET MAUI
AI & VoiceRAG, Qdrant, OpenAI, Anthropic, STT/TTS, VoIP, SIP
InfrastructureDocker, GitHub Actions, Linux, PostgreSQL, Redis, Firebase, Hetzner

Education

Higher Vocational Degree in Multiplatform App Development2022 — 2024
Higher Vocational Degree in Naval Mechanics2017