Joshua Kelly

CTO @ Flexpa & YC Founder

Today, I'm refactoring healthcare as co-founder and CTO of Flexpa. We can link identified claims data from anyone.

Previously, I was a solo-founder in Y Combinator's Winter 2020 batch. Before that I was CTO @ Universe, acquired by Live Nation in 2015 where I managed a product team of 30.

I also advise a small number of ambitious companies.

Talk to me about anything

Experience
13 years
Team building
60 hires
YC batch
W20
Language of choice
TypeScript

Stack Experience

TypeScript is my greenfield language of choice. Ruby (Rails) was the first language I loved. Elixir and Rust are my weekend project languages. When necessary, I can build in Python and Go too.

On the frontend, I usually work with React, Next.js, and TailwindCSS. My preferred design tool is Figma.

As far as protocols and query languages go, I launched a GraphQL API at Universe in 2017 (way before it became mainstream). I have special depth with OAuth - having launched Ticketmaster's production fan OAuth service.

I'm unreasonably effective at data modelling. PostgreSQL and SQLite (totally underrated) are my go-tos database-wise.

When I work on infrastructure and operations, I usually grab Terraform off the shelf first. I've built production systems on top of both AWS and GCP. The largest EC2 fleet I've deployed had over 300 instances. The best deployment is ECS Fargate.

Recently, my work in healthcare has led to special knowledge of protocols like FHIR.

Before anyone had heard about dog-themed meme coins and bored apes, I was building on Ethereum, Solidity, and web3.js at ETHGlobal (Waterloo, Denver, and San Francisco). I have also shipped code to Bitcoin Core.


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Talk to me about anything