About

Sebastian Castano Jara

Senior Software Engineer · Cali, Colombia

I'm a full-stack engineer with 8+ years building digital products. Currently working as a Senior FullStack Engineer, shipping products and untangling complex systems for companies across the Americas.

Outside of work, I build side projects. My current one is todo.valdemird.com, a task manager with AI scheduling, Pomodoro timer, and drag-and-drop. Built with Next.js 15, React 19, Prisma, and Tailwind CSS 4.

I spend a lot of time thinking about how to make AI actually useful when coding. Not just as a code generator, but as something that understands your project before writing a single line. I built a spec-driven development workflow that I use daily and write about on this blog.

What I work with

Frontend

ReactNext.jsAstroTypeScriptCSS/Design Systems

Backend

Node.jsPostgreSQLPrismaREST APIs

DevOps & Cloud

AWS (Certified)CI/CDDockerGitHub Actions

AI & Tooling

LLM IntegrationVercel AI SDKSpec-Driven DevelopmentCustom CLI Workflows

Journey

2022–Now Nearshore Tech Company

Senior FullStack Engineer

Shipping digital products for international clients. React, Next.js, cloud infrastructure. 4+ years and counting.

2020–2022 Software Consulting Firm

Software Engineer → Senior

Went from Software Engineer to Senior in under 2 years. Full-stack work across multiple client projects.

2019–2020 Dev Agency

Software Developer

Real-time transactional services, group video calls, drag-and-drop dashboards, PDF report generators. React, Node.js, Firebase, AWS.

2017–2018 Independent

Freelance Engineer

Android apps, Arduino IoT integration, Firebase backends. Mobile apps and delivery platforms.

2016–2017 Software Studio

Junior Developer

First professional role. Where it all started.

Education

2026 B.Eng. Systems Engineering, Universidad del Valle
2018 Technology Degree in Information Systems, Universidad del Valle
2016 Technology Degree in Game Development, SENA

Certifications

2023 AWS Certified Cloud Practitioner
2020 EF SET English C2 Proficient
2020 Learning How to Learn, Coursera

What I believe in

Spec-driven development

Write the spec before the code. Let the LLM be your co-architect, not just your typist.

Build in public

Share what you learn. The best way to solidify knowledge is to teach it.

Beauty & function

Tools should be beautiful AND functional. Design is not decoration, it's communication.

Get in touch

I speak Spanish (native) and English (C2 proficient).