yeray@portfolio:~$ cat about.md

Yeray Díaz

Product engineer with 10+ years of full-stack experience and a growing obsession with making AI agents actually useful in production. Currently at MongoDB, where I own a public-facing pricing tool and built a working MCP server that enables AI agents to query and recommend Atlas pricing. Deep expertise in TypeScript, Python, React, and cloud infrastructure — now channeled into building AI-powered developer tools and agent systems.

[ GitHub ][ LinkedIn ][ Email ][ Blog ]📍 Madrid, Spain (Remote)

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experience

Senior Engineer

@ MongoDBSept 2024 – Present

Led end-to-end delivery of Public Atlas Pricing Calculator — large-scale, public-facing full-stack app
Built MCP server prototype enabling AI agents to query Atlas pricing.
Delivered Enterprise APC PoC in 1 week — feature with multi-million dollar revenue potential
Pioneered load testing and prerendering strategies, setting team performance benchmarks
Force multiplier across teams — guided integrations, mentored engineers, collaborated with Product, Marketing, Security & Analytics

TypeScriptTanStack StartReactJavaMongoDBMCPOpenAI API

Software Engineer L3

@ MongoDBJan 2023 – Aug 2024

First engineer on Atlas Pricing Calculator — became go-to technical reference, rated "Consistently exceeds"
Architected 10x backend performance improvement via caching layers and ahead-of-time computation
Led Tiered Subscription pricing and Multi-region/Multi-cloud calculator — scoped, presented to PM, shipped to prod
Set up Sentry monitoring, resolved 17 issues — earned "the overachiever" recognition
Acted as de facto Product Manager while PM was out; contributed to MongoDB Atlas core repository — 2nd in department

TypeScriptReactNode.jsJavaMongoDBKubernetesDockerDrone CI

Full-stack Developer

@ Universia (Santander Group)Jan 2019 – Dec 2022

Architected and led front-end for Universia Jobs — Santander Group's global employment portal serving 10+ countries, coordinating an 8-developer team across Angular 7, Universal SSR, and i18n
Designed event-driven microservices architecture (DDD, CQRS) with Django REST + Nest.js — PostgreSQL for writes, Elasticsearch for reads, gRPC for inter-service communication
Built real-time job market analytics pipeline processing millions of events via Kafka + Elasticsearch; designed ETL pipelines in Python
Owned SRE responsibilities: Kubernetes orchestration, pod optimization, Grafana dashboards, Graylog log management

AngularDjangoNest.jsPostgreSQLElasticsearchKafkaKubernetesgRPC

Front-end Developer

@ Sopra SteriaNov 2017 – Dec 2018

Built Bankinter's mortgage simulator (Partnet) from scratch — customer-facing fintech tool for Spain's 5th largest bank (Angular 4)
Core developer on Popcoin, Bankinter's robo-advisor investment platform — complex reactive state management with ngrx/RxJS

AngularngrxRxJSTypeScript

Front-end Developer & UX Designer

@ VAYOO IntelligenceJan 2017 – Nov 2017

Led UX redesign that modernized the product's interface and improved usability
Migrated mobile app from legacy AngularJS/PhoneGap to Ionic 3 — reducing maintenance burden and enabling faster feature delivery

IonicAngularPhoneGap

Full-stack Developer

@ Bizeu ConsultingOct 2014 – Sept 2016

Built web platforms across multiple client projects using Python (Django, Tornado) with MySQL
Created a WordPress plugin for a photo-sharing contest — ~500 users registered
Introduced automated testing with Selenium; managed Linux infrastructure (Nginx, Gunicorn)

PythonDjangoTornadoMySQLSelenium

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