Finbar Giusti
About me
I am a software engineer, currently working at Stripe.
I like working with high-velocity, complex systems.
If you’d like to talk, send me an email at finbar(at)finbar.co.
Blog
Recent entries from my blog:
Making the blog
2026-04-14
This is the first entry in my blog. I will discuss how I added a blog to my site using lua. In the end I was able to add a blog summary on my home page as well as individual blog entry pages in just a few lines of code.
Work Experience
Software Engineer
Stripe
August 2025 - present
Worked in the Authentication team at Stripe, handling payments performance optimization from the POV of 3DS. This involves optimizing the boundaries between regulatory compliance, payment conversion, user experience and latency.
Notably, I shipped an internal optimization saving ~$2M in transaction fees yearly. I was also largely involved in shipping Standalone 3DS, for example single-handedly building the Analytics Dashboard, the Stripe.js sdk for users, as well as the future payment 3DS setup.
Also worked on many impactful projects I cannot disclose.
payments finance machine learning high assurance engineering PCI compliance ruby java typescript gocode data engineering
Software Engineer Intern
Stripe
March 2024 - September 2024
Worked in the Authentication team on a couple of impactful projects I cannot disclose. I can disclose that these changes positively impact >20M transactions per year as well as protecting Stripe from regulatory changes in the future.
payments machine learning high assurance engineering PCI compliance ruby gocode
Freelance Developer
Self-Employed
Since forever - Can't stop
I’ve been a Freelance developer / indie hacker as long as I can remember. See my projects below to see some of the things I worked on that are publically accessible.
whatever I can get my hands on
About this site
This site was written using lua. This was not for conveniance or required features. Rather I was on PTO for a week and I thought it would be fun.
I did not use any LLMs in building it.
It works using a minimal lua templating language I built called elua. It is easy and fast, but generally unsafe, and is not recommended for use.
I wrote some basic instructions for how to use elua here.
You can see the source of this website on github here.