Juan Pablo Calao Pérez

JUAN CALAO

Software Engineer

me@calaojuanpablo.com · @CalaoJuanPablo · GitHub · LinkedIn · X

Profile

Product-focused Software Engineer with 8+ years building web applications with React, Next.js, TypeScript, and Node.js. Experienced across the full product lifecycle — from identifying business problems and proposing solutions to shipping backend APIs, integrations, and polished UIs. Track record of owning features end-to-end in fast-moving environments: replaced a costly third-party service with a custom-built solution, owned CMS-to-production migrations, and built a training analytics platform solo. Comfortable with ambiguity, small teams, and wearing multiple hats.

Skills

Frontend: React, Next.js, TypeScript, JavaScript (ES6+), HTML, CSS/SASS

Backend: Node.js, NestJS, Next.js API Routes, Prisma, PostgreSQL, REST APIs, Webhooks

State & Data: TanStack Query, Redux, XState, GraphQL (client)

Integrations: Auth0, Salesforce, Strava API, Storyblok, Strapi

Infra & Deployment: Vercel, Render, Docker Compose, GitHub Actions

Testing: Jest, Testing Library, Storybook, MSW, Cypress

Projects

Founder / Software Engineer Ongoing
VECTA Train

Side project

Designed and built a running training analysis platform end-to-end: NestJS + Prisma + PostgreSQL backend, React frontend.
Implemented training load calculations (Banister’s TRIMP) and athlete performance modeling.
Integrated Strava API via webhooks for automatic activity ingestion.
Set up full deployment pipeline: frontend on Vercel, API and PostgreSQL on Render, Docker Compose for local development, CI/CD with GitHub Actions.

Experience

Frontend Engineer
Beon Tech — Marvin Windows & Doors

Jan 2025 – Present

Identified and proposed the replacement of Algolia with a custom-built solution, cutting third-party costs ~60% (tens of thousands USD annually) — owned it from business case to production.
Built and maintained backend services via Next.js API routes: product listing endpoints with server-side filtering and data mapping, Storyblok SDK integration.
Implemented webhooks to reindex content on story add/update/delete, plus a cron job for full-site reindexing.
Owned the Display Guide migration from WordPress to Next.js + Storyblok — scoped, planned, and delivered.
Led development of the CMS-driven marketing platform powering the main public website.
Deployed and managed the platform on Vercel.

Frontend Engineer
Zemoga — Nightshift (FAANG, NDA)

Sep 2023 – Jan 2025

Developed high-performance marketing and retail experiences for a major global tech company, including interactive in-store tablet experiences and a global workshop booking platform.
Built reusable animation and transition modules, focusing on performance, modularity, and consistency across multiple user touchpoints.

Frontend Engineer
Zemoga — Walmart

Dec 2020 – Sep 2023

Developed and maintained critical checkout flows on Walmart.com — including marketplace product flows — covering 6+ delivery modes across order placement, payment, and fulfillment.
Managed complex client-side data via React Query and GraphQL, maintaining a contract-based data layer unifying cart, payment methods, delivery modes, and cost breakdowns.
Applied useMemo and React.memo to optimize rendering across delivery-mode-specific component trees.
Implemented internationalization (react-intl) supporting English, Spanish, and French across US, Canada, and Mexico markets.
Contributed to unit, integration, and E2E testing strategies using Jest, Testing Library, MSW, and TestCafe.
Collaborated in a team of 6, participating in architectural discussions and translating decisions into production-ready implementations.

Frontend Engineer
Simetrik (YC W18)

Jul 2020 – Dec 2020

Owned the company’s main website end-to-end at an early-stage YC startup: landing page, signup flow, and content platform.
Built the authentication flow from landing page through Auth0, with Salesforce integration for lead capture.
Maintained Strapi CMS integration and built the blog platform supporting content creators.
Worked directly with the VP of Growth, translating growth objectives into shipped features.

Frontend Engineer
Ideaware — Luna Care

Apr 2020 – Jul 2020

Built patient and therapist registration flows — dual-sided user onboarding — with form validation and XState state management, working against a Ruby on Rails backend.
Built a clinical dashboard displaying treatment data using React and Chart.js, consuming a REST API.

Frontend Engineer
Ideaware — Blizzard

Oct 2019 – Apr 2020

Built components for the Overwatch League main website and team pages.
Developed new functionality for existing design system components, sourcing content from a CMS (ContentStack).

Frontend Engineer
Ideaware — Ask Method Company

Apr 2019 – Oct 2019

Built landing pages and multi-phase flows for marketing sales funnels.

Frontend Developer
SimpleLegal

Oct 2018 – Apr 2019

Developed a legal document generation platform using React, Redux, and Firebase, managing global state and dynamic document workflows.
Built reusable UI components using Material UI.

Earlier Experience

Finsocial — Data Analyst (2018): Built data visualization tools and dashboards using R (Shiny) and Tidyverse.

Universidad del Norte — Data Analyst (2017): Developed energy demand analysis tools and financial models using Excel and R.