Leonardo Hemming · Senior Full-Stack Engineer · EN / PT-BR

React & Node products that hold up in production.

7+ years shipping payments, AI and high-traffic products for teams in the US and Europe. Don't take my word for it, ask my digital twin.

Ask my digital twin
Download CV ↓
based
brazil
hours
us, live

origin: brazil
routes: br → mia · nyc · sfo
build: 7fbefe5

E2E pipeline runtime, via test sharding
22→5min
of bookings handled by an AI agent
70%+
PCI payments at 99.9% uptime
500K+/yr
monthly sessions on an app I shipped
1M+/mo

01 · About

24 years old. Seven of them in production.

I'm Leo, a software engineer from Brazil. I shipped my first production code as a teenager and never really stopped.

Freelancing taught me what no course does: clients on the other side of the world, deadlines that don't move, and nobody to hide behind when something breaks. So I learned to own the whole thing, from the first call to launch day and every day after.

Since then I've built a payment gateway that can't go down, AI that books medical appointments in three languages and a storefront that serves a million sessions a month. Different industries, one standard: if it ships, it holds up.

Off the clock I'm usually planning the next trip, or watching Grêmio, my football team. Ninety minutes of that has taught me more about staying calm under pressure than any on-call rotation.

name
Leonardo Hemming
age
24
based
Brazil
hours
US working hours
stack
React · Node · TypeScript
off
travel · football (Grêmio)
fuel
coffee, black

02 · Interview me

Ask my digital twin.

An AI version of me that only knows my real work. It won't make things up. When it doesn't know something, it hands you over to the real Leo.

Leo's twinonline, replies in secondsAI · grounded in my CV

    Chats are saved so I can keep improving my twin. Please don't share anything sensitive. Privacy

    03 · Experience

    Where I've made a difference.

    1. NativePath sells to customers all over the US, and its online store gets more than a million visits a month.

      Every release sat waiting 22 minutes for automated tests, and the store had to stay fast while the team kept shipping.

      I made the pages lighter and quicker to load, added live monitoring to catch errors early, and split the tests to run in parallel.

      Releases are now tested in 5 minutes instead of 22, and the store scores above 90 out of 100 on speed.

      −77%

      time to test every release

      Miami, FL · remote

    Where it started: Univates, 2021, my first job as a junior developer.

    04 · In their words

    Don't take my word for it.

    • He demonstrated professionalism, technical expertise, and a strong commitment to deadlines and quality.

      In addition to his skills in web development, he also stood out for his clear communication and willingness to make adjustments whenever necessary. I would definitely recommend him for any project requiring technical precision, creativity, and efficiency.

      Sangar ZucchiIT Consultant · Client via Workana

    • Leo is reliable, easy to communicate with, and brings a positive mindset to the work environment.

      During our time together at NativePath, Leonardo served as a Software Developer on our team. He demonstrated a strong commitment to team goals, was always open to receiving feedback, and maintained a collaborative approach to everyday tasks.

      Lucas TanakaFull Stack Engineer · Teammate at NativePath

    Verbatim from my LinkedIn recommendations ↗

    05 · Code

    Still writing code for fun.

    github.com/LdSH-dev ↗

    552 contributions in the last year · 126 active days

    06 · Performance

    Is this site fast? Let Google tell you.

    Press the button and Google's PageSpeed tool opens this live site on its own servers and grades it from 0 to 100. Anything above 90 is what Google calls fast. Takes about 20 seconds.

    No results yet. Pick mobile or desktop and press Run live test.