Software
Engineer and
Designer

for lack of a better word...

with over 8 years of experience building for start-ups in San Francisco, New York, London, Amsterdam, and Barcelona.

Me

what I've built

2026

Building my firsts side projects in robotics

I'll update this very soon as I happily escape JavaScript and web/cloud freakshow for the better. Getting my hands dirty with microcontrollers, RTOS, and low-level programming languages like C and my beloved Rust 🦀. Exploring hardware interfacing, sensor integration, and robotics algorithms to create autonomous systems and satisfy my designer curiosity at the same time. No idea how many unfinished projects I'll have by the end of 2026, but finished or unfinished they'll probably suck.

2025

SelfSend email-sanitizer-api, an Open Source Email Sanitizer API

A high-performance and secure REST/GraphQL API built with Rust, MongoDB & Redis for verifying email addresses for free with extremely high accuracy rates. Maintains sender reputation by validating, deduplicating, and pruning inactive emails with algorithms that processes more than 24 types of validations with the speed of Rust, including not only syntax validations but also DNS/MX Records, disposable email detection and many others.

2024

UX/UI themes on iamtonysanchez.com/art

ecommerce platform specializing in pixel-perfect web app templates engineered to achieve perfect 100 scores across all Lighthouse categories (Performance, Accessibility, Best Practices and SEO). Built with modern frameworks like Next.js and Tailwind CSS, each template is optimized for Core Web Vitals, responsive design, and semantic HTML, ensuring blazing-fast, accessible, and SEO-friendly websites out of the box. Custom payments gateway integrating Stripe and PayPal APIs, with full control over the checkout flow. More than 120 daily visits.

2023

Writefull, AI for academic writing

Global leaders on AI for academic writing years earlier than Chat-GPT release and trusted by Cambridge University Press and others. Natural language processing (NLP) to deliver real-time, context-aware writing enhancement for technical and academic texts. Integrated with IDEs and text editors via APIs, as well as Microsoft Word and Overleaf. It provides syntax correction, paraphrasing, and terminology suggestions. Built on transformer architectures with fine-tuned language models trained with millions of published papers, it supports LaTeX and Markdown workflows.

2022

Folio Wallet and other blockchain solutions by Smartmatic

Technology used in the USA elections, Canada, Brazil, Italy regional elections, Philippines and other global governments. Decentralized, non-custodial wallet leveraging smart contracts and Web3.js for seamless interaction with blockchain networks. Built with zero-knowledge proofs (ZKPs) for enhanced privacy, it offers secure key storage, and cross-platform compatibility (iOS, Android, web app and browser extensions).

2021

eEvidence, global leaders on email certification

Platform for email certification and eSignature solutions, leveraging PKI (Public Key Infrastructure) and blockchain-based timestamping for tamper-proof document integrity. It complies with eIDAS regulations, offering AES-256 encryption, multi-factor authentication (MFA), and audit trails for legal admissibility. Trusted by enterprises worldwide, it ensures seamless integration with enterprise systems via RESTful APIs and supports cross-border eSignature workflows with advanced biometric verification.

2020

Browser-Based Network Packet Sniffer

Cutting-edge TypeScript-powered tool designed to intercept, analyze, and visualize HTTP/HTTPS and WebSocket traffic in real-time. Leveraging the Service Worker and Performance APIs, it captures request metadata, headers, and payloads, enabling deep packet inspection. With advanced filtering, real-time updates, and export capabilities, designed for debugging, security auditing, and optimizing web applications.

2019

Internal tool for corporate use in ETL Global

A high-performance, data-intensive solution for automated ledger balancing, tax compliance, and multi-currency support, built on double-entry accounting principles. Features a secure, robust database architecture with AES-256 encryption, TLS 1.3, and Redis caching for optimized performance. Supports real-time forex aggregation and dynamic tax computation. Scalable via sharding and microservices.

2018

API consuming Hobby Web App for Tourism

Integrates with the Viator API to provide a unified platform for searching, comparing, and booking global attractions. Built with GraphQL for efficient data fetching, it features real-time availability checks, dynamic pricing comparisons. Mobile-friendly UX.