Joshua Kelly

YC Founder & CTO @ Flexpa

Today, I'm building developer tooling for healthcare as a co-founder and CTO of Flexpa. We've raised from some of the best VCs in the world including General Catalyst and a16z.

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.

The breadth of my skills across engineering leadership, product development, and startups is available on a fractional or advisory basis to select companies.

Contact me about fractional engineering leadership

Experience
12 years
Team building
55 hires
Fundraising
$14.5m
Language of choice
TypeScript

Stack Experience

TypeScript (ES6+, Node.js) 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.

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).


Select Projects


More

Contact me about fractional engineering leadership