Every experience teaches us something practical — a new mental model, a new way to operate, a new way to see problems. The kind of thing that’s obvious once you’ve walked the walk, but invisible until you have. This blog will be a place for sharing some of those learnings.
This list came out of a session as AI Interviewer, mapping years of Javier’s building into topics worth writing about. Past experiences worth documenting, and the future build they happen.
Big Tech
Building Dev Communities Across 14 Countries — How I expanded Microsoft Student Partners across Latin America by picking up the phone, one university at a time.
Selling Windows Phones Nobody Wanted — What it’s like selling a product you love that the market doesn’t.
How Enterprise Tech Sales Actually Work — Seasonality, relationships, and the playbook I built for selling against Android and iPhone.
Making Your Work Visible — A lesson from my boss at Microsoft: if you don’t tell people what you did, nobody knows you exist.
Design Documents at Amazon — How a one-pager replaced hours of meetings — and how I got the quiet people to vote.
Reducing Interview Uncertainty with Probability — Using Glassdoor data to narrow down what’s likely to come up and stop studying in the dark.
Algorithms and Big O for the Self-Taught — Why brute-force first always works, and how thinking in complexity changed the way I design infrastructure.
Government & Elections
Digitizing Electoral Operations Solo — How I won my first government contract by being faster and cheaper than actual software companies.
Building a Volunteer Registration System — Registering thousands of election volunteers with a hierarchical access model I built from scratch.
Competing with IBM in Belize — Building a ballot scanning app with OpenCV, winning a contract against IBM, and watching poll workers start to disappear.
Selling Software to Government — What I learned about procurement, compliance, and how government contracts actually work from the inside.
Banking
Calling Every Manager to Find a Problem to Solve — How I figured out what to build when my only instruction was “innovate.”
Reverse Engineering a Bank’s Core Protocol — No documentation, proprietary software, a prototype that turned 12-month projects into 2-month projects.
Side Projects
Basic Computer Security for the Rest of Us — Not hacking, not IT. Just the street-smart basics everyone should know to avoid the obvious traps online.
Google Sheets as Infrastructure — The best tool is the one people already know how to use. How I used it to track 15 million in donations for a social org — and why it worked better than a real database.
Building an Interview Copilot Chrome Extension — A Chrome extension that listened to both sides of a call and suggested answers in real time — before that was a product category.
Transferring Files the Visual Way — When VNC is the only thing you have and you need to move files, you get creative.
When I Had to Build My Own GitHub — GitHub’s rate limits would have killed my product’s first-user experience. So I built a custom git backend on Cloudflare R2.
Reverse Engineering ASP.NET Binaries — When the CTO is gone and all that’s left are compiled DLLs on a server.
Community
Pulling Off the First Startup Weekend in Guatemala — A friend’s idea that became a real event.
Organizing a Hackathon Against Domestic Violence — Partnering with the IDB and Second Muse to build apps that could actually help.
Doing a TEDx — What I talked about and what I learned from preparing it.
Posts go live as they’re ready. Subscribe or check back.