Nestor G Pestelos Jr

Software engineer since 2001. Manila, UTC+8.

[email protected] · GitHub · LinkedIn · X · Calendly · Writing

I maintain production Ruby on Rails systems. These days agents write much of the code, and I review every change before it goes out.

Writing

All writing · ELI5 · Trees · Reference

To understand legacy Ruby on Rails or wire agents into a real codebase, write me or book 25 minutes. Sample of a written read. I work from Manila, UTC+8, so US teams get overnight coverage.

My Work

What I Do

Ruby on Rails Modernization & Reliability

Upgrade aging Ruby on Rails codebases without breaking production. Most recent: modernized a 1M+ line Ruby on Rails application to 91% test coverage with 3,797 passing tests and an 8-check pre-commit hook. A fixed-price written readiness read is available.

Payment System Integration

End-to-end payment infrastructure — Stripe, Square, PayPal, Avalara tax. Integrated payment gateways for e-commerce platforms serving US, AU, and NZ markets.

Agents in the Work

I wire coding agents into real codebases with human review, version tracking, and a fallback when the model is wrong. The deliverable is software, not an agent product. Demo of that split: Play · guest-stay-agent.

Open Source

Family & Hobby