Full Stack Engineer · Headless CMS · Next.js
Full Stack Engineer building
Headless CMS, Sitecore XM Cloud, and Next.js platforms.
I design content architectures, SaaS products, and production frontends for teams that need performance, scalability, and maintainable delivery from the data model to deployment.
Currently
Full Stack Engineer at Verndale
Building
Pathwise · Trainr
Based in
Quito, Ecuador
Open to
Freelance CMS architecture, senior engineering roles, and focused technical advisory work.
About Sebastián
Full stack engineer.
CMS architect. Product builder.
I am a full stack engineer based in Quito, Ecuador. I specialize in headless CMS platforms, Sitecore XM Cloud, Optimizely, Next.js, and composable architecture. I build the content model, the application layer, and the deployment path that turns the architecture into a working product.
My approach is to understand the constraint before writing the first line: what needs to be reliable, what needs to stay flexible, and where the integration boundaries are. The clean architecture and the fast delivery are usually the same solution.
The products I build on the side start from problems I could not solve with existing tools. Pathwise, Trainr, FocusLock, Forge, and Pantry Burn each answer a specific gap with a small, shipped system.
Stack
What I build
Real systems with clear constraints.
CMS platforms
Headless CMS implementations with content models, component contracts, GraphQL delivery, and publishing workflows that teams can maintain.
Headless CMS architectureSaaS apps
Focused products with clear data models, practical billing or auth decisions, and frontends that stay simple after the first release.
SaaS and app projectsScalable frontend architectures
Next.js and TypeScript systems for CMS-driven sites, product surfaces, internal tools, and the edges where content meets application logic.
Next.js CMS developmentRecent work
Recent work / shipped systems.
Dream Journal
A local-first web app for recording dreams quickly, marking no-dream days, and reviewing patterns over time without accounts, cloud sync, or backend infrastructure.
Forge
A browser-based developer toolkit with privacy-first, client-side utilities for visual QA, local API mocking, text transforms, and in-browser background removal with deterministic mask editing.
FocusLock
A minimal focus timer for iPhone that counts every time you leave the app mid-session, then turns that into a brutally honest score.
Pantry Burn
A food-expiry tracker for iPhone that ranks what to use first, schedules local reminders, and stays focused on waste reduction instead of recipes.
Webtrace
A browser extension suite with five lightweight tools that run passively as you browse — tab time tracking, highlight saving, focus goals, inactive tab flagging, and price tracking.
Trainr
Web platform for freelance fitness coaches to manage clients, deliver workout plans, and track progress across gym, running, CrossFit, Hyrox, and any other training style.
Arrived
Safe-arrival notification app. Your trusted contacts get a quiet notification when you arrive or leave a place — so no one has to remember to send the "I got home safe" text.
Pathwise
AI-powered learning platform that builds a personalized week-by-week roadmap from a 5-question onboarding conversation.
Background
What I know
and why I build.
Founder / Engineer
Self-Directed · 2023 — Present
End-to-end product engineering — Pathwise (AI learning platform), Trainr (coaching and client management), FocusLock and Pantry Burn (productivity utilities), and a multi-agent algorithmic trading system. TypeScript, Next.js, Supabase, Python.
Full Stack Engineer
Verndale · 2023 — Present
Multi-site headless CMS platforms on Sitecore XM Cloud, Contentstack, and Optimizely — content architecture, GraphQL component systems, build-time per-property theming. Authored verndale-cms-mcp, an MCP server that automates component scaffolding from Confluence specs. Speaker at Sitecore User Group Ecuador.
Earlier
REST API development in Node.js and C#/.NET — schema design, database migrations, AWS deployments, and CI/CD pipelines. Container-based workflows with Docker and Linux systems fundamentals. Backend before the CMS work, which is why the architecture side comes naturally.
MSc Full Stack Web Development · UNIE - INESDI
Featured writing
Selected notes on systems,
CMS architecture, and shipped products.
View all posts →Building sebasab.dev — decisions, tradeoffs, and why I didn't use Webflow
How I built this portfolio from scratch with Next.js App Router, Tailwind v4, and MDX — and the reasoning behind every major library choice.
Handling Hierarchical Taxonomies in Sitecore Search
Sitecore's search functionality doesn't natively support hierarchical facets.
Advanced Web Crawler 101: Sitemap Trigger Extractors
When working with Sitecore Search , the foundation of a good experience is how well your crawler is configured.
Availability
Available for freelance / opportunities.
I'm open to selective freelance work around headless CMS architecture, Sitecore XM Cloud, Optimizely, and Next.js, plus senior full stack roles where product thinking and execution both matter.