Senior Full-Stack & AI Engineer · Tech Lead

Yagel
Salazar.

Yagel Salazar Reyes — Senior Full-Stack & AI Engineer · Tech Lead
8+ yrs

I build AI agents & RAG systems people love to use.

8+ years taking ideas from backend architecture to the last pixel of the frontend — for brands like Disney, Clara and the LA Clippers. Today I build LLM agents and RAG pipelines that run in production, with evaluation and observability built in.

LOC
Actopan, Hidalgo, México
BASE
Mexico City · Remote-first
Disney✦Clara✦Softtek✦Globant✦LA Clippers · NBA✦Citibanamex✦Honeywell✦Alsea✦Hard Rock✦Roku × HBO✦
Profile

Senior Full-Stack & AI Engineer and Tech Lead with 8+ years shipping type-safe systems end to end — now with AI at the core. I design multi-step LLM agents and RAG pipelines, architect secure event-driven microservices, optimize PostgreSQL data layers and build polished React frontends with genuine UX/UI sensibility.

  • 01

    AI / LLM Engineering

    Multi-step agents on LangGraph, RAG over Azure AI Search, evaluation with test datasets and LLM-as-judge scoring — traced end to end with Langfuse.

  • 02

    Backend Architecture

    Microservices & APIs in Node.js, NestJS and TypeScript — GraphQL Federation, Kafka event streams, OpenAPI contracts — with PostgreSQL schema design and query optimization.

  • 03

    Frontend & UX/UI

    React, React Native & Next.js with design systems, Web Components, D3.js/SVG data visualization and a sharp eye for interfaces that feel right.

  • 04

    Cloud & DevOps

    CI/CD pipelines, Docker deploys and cloud infrastructure across AWS & Azure.

  • 05

    Quality & Testing

    Comprehensive Unit and E2E coverage with Jest, Cypress and Pytest to keep releases reliable.

  • 06

    Technical Leadership

    Leading Agile teams, setting architecture direction and mentoring toward clean code.

  • 07

    Mobile, end to end

    React Native, Kotlin & Swift — production apps for fintech, hospitality, retail and live events.

AI Engineering

AI in production.

Agentic RAG platform for a Fortune 500 beverage company — Softtek, 2026 — present.

  • 01

    Agents & tools

    Multi-step agents on LangGraph — stateful graphs, conditional routing, retries and handoffs between steps — with per-agent system prompts, Pydantic-typed tools, schema-validated structured outputs and persisted per-user memory.

  • 02

    Retrieval

    Structure-aware chunking with overlap, hybrid vector + keyword search on Azure AI Search with semantic re-ranking, metadata- and permission-aware filters, and incremental re-indexing from SharePoint, Confluence and S3.

  • 03

    Evaluation & guardrails

    Test-case datasets re-run on every prompt or model change, LLM-as-judge scoring recorded in Langfuse, schema validation, mandatory citations, out-of-domain refusals and human review of traces before each release.

  • 04

    Cost, latency & observability

    Per-step and per-tool tracing of tokens, latency and cost in Langfuse; model routing by task; streaming responses with timeouts and retries; embedding and response caching plus context trimming.

  • 05

    AI in the dev loop

    An n8n + LLM pipeline that reviews every GitHub pull request automatically.

Experience

Track record.

Reverse-chronological — global brands across beverages, fintech, streaming, retail & sports.

  1. Softtek

    Senior Full-Stack & AI Engineer · Tech Lead, AI Platform

    Apr 2026 — Present

    Ciudad de México · Hybrid

    Global IT services — client: a Fortune 500 beverage company.

    • Lead development on an Nx monorepo for the client’s next-generation, multi-tenant sales platform — Next.js web app, NestJS microservices with GraphQL (Apollo Federation) and a BFF layer, Kafka-based event-driven integrations, PostgreSQL; deployed with Docker, GitHub Actions and Argo CD on AWS.
    • Own the AI platform — multi-step LLM agents and RAG pipelines with LangGraph, LangChain, OpenAI and FastAPI over an Azure AI Search vector store, evaluated and observed with Langfuse — and its LLM-powered UI: a conversational interface with streaming responses and agent workflows in Next.js/React.
    • Develop Python data ingestion & retrieval services (Snowflake/Snowpark, Pandas, SQLAlchemy) integrating SharePoint, Confluence and AWS S3 sources.
    • Ship the field-sales React Native + Expo mobile app with Redux Toolkit, TanStack Query, Apollo Client and MUI; shared UI as StencilJS Web Components; OpenAPI/Swagger contracts with generated typed clients; enterprise SSO with OAuth 2.0 / OIDC (Azure Identity).
    • Automated code review with an n8n + LLM pipeline on GitHub pull requests; tests with Jest, React Testing Library, Supertest and Pytest; sprint demos with client stakeholders.
  2. Clara

    Senior Full-Stack Engineer

    Apr 2025 — Apr 2026

    Remote · México

    Unicorn fintech — corporate spend-management platform.

    • Architected secure, type-safe multi-tenant microservices with NestJS, GraphQL (Apollo Federation) and Prisma over PostgreSQL, with event-driven processing on Kafka and RabbitMQ for real-time transactions and automated financial reconciliation.
    • Shipped the Next.js web app and React Native + Expo mobile app with Redux Toolkit, TanStack Query, Apollo Client and MUI / MUI X; shared UI as StencilJS Web Components (Shadow DOM) and embedded third-party flows in sandboxed iframes with postMessage and a strict CSP.
    • Published OpenAPI/Swagger contracts for REST services with generated typed clients; engineered on an Nx monorepo with Docker and GitHub Actions (Fastlane/Codemagic for mobile); tested with Jest, React Testing Library and Supertest.
  3. Globant

    Senior Full-Stack Engineer & Tech Lead

    Jun 2022 — Apr 2025

    Remote · Global clients

    Global digital consultancy — marquee client engagements.

    • Disney — as Tech Lead, architected internal dashboards with interactive D3.js/SVG visualizations (time series, rankings, drill-down tooltips) and streaming-management services (Node.js, Express, NestJS, TypeScript) with Kafka event streams and OpenAPI contracts with generated clients; containerized deploys with Docker on AWS.
    • Disney — secured and integrated them with OAuth 2.0 / OIDC SSO and JWT flows, StencilJS Web Components and sandboxed iframe + postMessage + CSP embedding; Unit + E2E testing with Jest and Cypress.
    • LA Clippers (NBA) — data-driven drag-and-drop web app in React, Next.js and TypeScript with D3.js/SVG charts for game-day metrics and PostgreSQL persistence, scaled across Azure and AWS for high-traffic game days.
    • Alsea Omnicalidad (Starbucks, VIPS, Burger King, Ginos, Foster’s Hollywood…) — multi-tenant, multi-brand in-restaurant & delivery ordering app in React Native, Kotlin and Swift with Paycomet payments, Firebase, PostgreSQL and Docker for the Spanish market.
    • Hard Rock “Unity” — multi-property rewards & reservations app for hotels and casinos in React Native and NestJS with Stripe payments on AWS.
  4. Honeywell

    Full-Stack Developer

    Feb 2022 — Jun 2022

    México

    Honeywell R&D center — warehouse-management web app.

    • Delivered a warehouse-management platform with a React/Next.js front end and a C#/.NET + GraphQL backend on Azure with SQL Server.
  5. Globant

    Full-Stack Engineer

    Mar 2021 — Feb 2022

    Remote · Global clients

    Global digital consultancy — marquee client engagements.

    • Yarta (EagleAI, Market Intel, Livestock) — global farm-market tooling; designed and optimized SQL Server & PostgreSQL schemas with Java/Spring Boot and Node.js backends feeding a Next.js frontend.
    • Citibanamex — Account Opening Partners — banking web UI for credit-card assignment and credit-line management with Maestro Avoka, Angular, Java/Spring Boot and a Headless CMS.
    • Roku × HBO — performance optimization of the HBO app on Roku OS (SceneGraph, BrightScript, GraphQL) for the Justice League release; plus Pokerlabs, an internal story-pointing tool (React, Node.js, MongoDB).
  6. KIORU

    Frontend Developer

    Aug 2019 — Mar 2021

    México

    “Saeko V2” — multi-role school-management platform.

    • Built a role-based school-management web app in React with Storybook-driven components, Redux and reusable hooks.
  7. Actosoft

    Full-Stack Developer

    Jun 2018 — Dec 2019

    México

    Transport & restaurant products.

    • Built “BuntiApp” (transport) and “Leaf” (restaurant web app) with Node.js, Express, MySQL/MongoDB, React, TypeScript, Styled Components, GraphQL and Kotlin/Android Studio.

Earlier — Brounie (“Plano Firme”): frontend web & mobile for a building-materials delivery platform with admin panel and mobile client (React, Redux, Node.js, GraphQL, Kotlin).

Selected work

Things I’ve shipped.

  • AI Platform

    01
    AI Engineer · Fortune 500 beverage company

    Agentic RAG platform in production: LangGraph agents, hybrid retrieval on Azure AI Search, LLM-as-judge evaluation, Langfuse tracing and an LLM-powered conversational UI with streaming responses.

    • LangGraph
    • LangChain
    • OpenAI
    • FastAPI
    • Azure AI Search
    • Langfuse
  • Disney

    02
    Tech Lead · Streaming

    Architected internal dashboards with interactive D3.js/SVG visualizations and streaming-management services with Kafka event streams, OAuth 2.0 / OIDC SSO and OpenAPI contracts; drove Unit + E2E testing.

    • NestJS
    • D3.js
    • Kafka
    • OIDC
    • Cypress
    • AWS
  • Clara

    03
    Full-Stack · Fintech

    Secure, type-safe multi-tenant microservices for a unicorn corporate-spend platform — Kafka and RabbitMQ event processing, real-time transactions and automated reconciliation.

    • NestJS
    • GraphQL Federation
    • Kafka
    • PostgreSQL
    • React Native
  • LA Clippers

    04
    Full-Stack · NBA

    A data-driven drag-and-drop web app for high-traffic game days — D3.js/SVG charts for game-day metrics, PostgreSQL persistence and multi-cloud scaling.

    • React
    • Next.js
    • D3.js
    • TypeScript
    • PostgreSQL
    • Azure
  • Alsea

    05
    Mobile · Multi-brand

    In-restaurant and delivery ordering across Starbucks, Burger King, VIPS and more — one multi-tenant app shipped for Spain.

    • React Native
    • Kotlin
    • Swift
    • NestJS
    • Firebase
  • Hard Rock

    06
    Mobile · Hospitality

    “Unity” — a rewards and reservations app for hotels and casinos, with Stripe payments on AWS.

    • React Native
    • NestJS
    • Stripe
    • Redux
    • AWS
  • Roku × HBO

    07
    Frontend · Performance

    Optimized the HBO app on Roku OS for the Justice League release — close to the metal in SceneGraph and BrightScript.

    • BrightScript
    • SceneGraph
    • GraphQL
  • Citibanamex

    08
    Full-Stack · Banking

    Account Opening Partners — web UI for credit-card assignment and credit-line management at one of Mexico’s largest banks.

    • Maestro Avoka
    • Angular
    • Spring Boot
    • Headless CMS
  • Yarta

    09
    Full-Stack · AgriTech

    Global farm-market management tools (EagleAI, Market Intel, Livestock) with optimized SQL Server & PostgreSQL schemas.

    • Java
    • Spring Boot
    • Next.js
    • PostgreSQL
    • SQL Server
Stack & expertise

The toolbox.

  • AI / LLM & RAG

    • LangGraph (multi-step agents)
    • LangChain
    • OpenAI
    • FastAPI
    • Pydantic
    • Prompt & tool design
    • Structured outputs
    • RAG (chunking, hybrid retrieval, re-ranking)
    • Azure AI Search
    • Langfuse (tracing & evals)
    • LLM-as-judge evaluation
    • Guardrails
    • n8n
  • Languages

    • TypeScript
    • JavaScript
    • Python (3.11–3.12)
    • Kotlin
    • Swift
    • Java
    • C#
    • SQL
  • Backend & APIs

    • NestJS
    • Node.js
    • GraphQL (Apollo Federation)
    • REST
    • OpenAPI / Swagger (generated clients)
    • Prisma ORM
    • Express
    • Java / Spring Boot
    • C# / .NET
    • Kafka
    • RabbitMQ
    • Multi-tenant microservices
  • Frontend

    • React
    • Next.js
    • React Native
    • Redux Toolkit
    • TanStack Query
    • Apollo Client
    • Material UI (MUI / MUI X)
    • Recharts
    • D3.js
    • SVG data visualization
    • Emotion
    • Tailwind CSS
    • Web Components (StencilJS / Shadow DOM)
    • Angular
    • Storybook
    • Vite
  • Data & Ingestion

    • Snowflake (Snowpark)
    • Pandas
    • SQLAlchemy
    • Scrapy
    • EasyOCR / OpenCV
    • BeautifulSoup
    • Azure Blob Storage
    • python-pptx / docx
  • Databases

    • PostgreSQL
    • MySQL
    • SQL Server
    • MongoDB
    • Snowflake
  • Mobile

    • React Native
    • Expo
    • React Navigation
    • Reanimated
    • Firebase
    • react-native-maps / Mapbox
    • Android Studio
  • Cloud

    • AWS (RDS, S3, Secrets Manager)
    • Azure (AI Search, Blob, Identity)
    • Microsoft Graph
  • DevOps & Tooling

    • Nx (monorepo)
    • Docker
    • GitHub Actions
    • Argo CD
    • Jenkins
    • CircleCI
    • Fastlane
    • Codemagic
    • Git
    • Bitbucket
    • CI/CD
  • Testing

    • Jest
    • React Testing Library
    • Supertest
    • Pytest
    • Cypress
  • Auth, Security & Payments

    • OAuth 2.0
    • OIDC / SSO
    • JWT
    • Passport
    • NextAuth
    • iframe sandbox + postMessage
    • CSP
    • Stripe
    • Paycomet
  • Methods

    • Agile
    • Scrum
    • Kanban
    • Clean Code

EDUCATION

B.Tech, IT Engineering

ITSOEH — Hidalgo, México · Full-Stack Web Development & Computer Science

2016 — 2020

LANGUAGES

Spanish — Native · English — Advanced

STRENGTHS

Leadership, critical thinking, fast learning, focus, creativity & management.

Contact

Let’s build
something together.

Open to Senior Full-Stack, AI Engineer and Tech Lead roles — remote-first or Mexico City. Available now.

↓ CV EN↓ CV ES