Alex Kroeger | Software Engineer, EMT

About

I'm currently working as an EMT at LIFEwest ambulance. I previously worked as a software engineer. In my free time you can find me swimming in the San Francisco Bay, birding, or playing chess.

Work Experience

LIFEwest Ambulance

EMT

Feb 2026 - Present

Emergency Medical Technician providing patient transport in the San Francisco Bay Area.

Circle

Senior Software Engineer

Feb 2024 - Jun 2025

Software engineer on the special projects team.

Phantom

Senior Backend Engineer

Feb 2022 - May 2023

Built the first backend services for Phantom to improve app performance and unlock new features.

a16z

Protocol Specialist

Aug 2021 - Nov 2021

Engaged with governance for crypto protocols in a16z's portfolio, including Uniswap and Compound.

0x

Software Engineer, Data Scientist

May 2019 - Aug 2021

Built tools for professional market makers to provide liquidity to 0x API users.

Coinbase

Data Scientist

Feb 2018 - Apr 2019

Supported Coinbase Pro (the exchange product) by informing product decisions with data.

Analysis Group

Analyst

Feb 2017 - Feb 2018

Economic consulting.

Federal Reserve Bank of New York

Research Analyst

Jun 2015 - Jan 2017

Research group.

Volunteering

Dolphin Club

Swim Commissioner

Dec 2024 - Present

Organize open water swimming events for club members in the San Francisco Bay.

Education

University of Notre Dame

2011 - 2015

Bachelor's Degree in Finance and Economics

Skills

JavaScript

TypeScript

Node.js

Python

SQL

Solidity

Terraform

Projects

Birds of SF

An automated Twitter feed of rare bird sightings in SF.

Side Project

Node.js

Updating the Ethereum Yellow Paper

Updated the Ethereum Yellow Paper for the London, Arrow Glacier, Gray Glacier, and Paris upgrades.

Side Project

EVM

Technical Writing

Publications

Refund Protocol: Non-Custodial Dispute Resolution for Stablecoin Payments

Circle Research

April 17, 2025

Temporary ERC-20 approvals: A cheaper & safer way to do DeFi

Circle Research

October 17, 2024

TXT2TXN: Using AI (LLMs) for Intent-Based Applications

Circle Research

August 8, 2024

A New Era of Content Publishing and Licensing on the Blockchain

Bitcoin Magazine

August 4, 2017

Counterpary has Reached its Millionth Transaction

Bitcoin Magazine

July 17, 2017

The Moonbeam Scaling Network: A 'semi-decentralized' scaling solution

Bitcoin Magazine

June 16, 2017

The Pre-Crisis Monetary Policy Implementation Framework

Federal Reserve Bank of New York Staff Report

March 2017

Monetary Policy Transmission before and after the Crisis

Liberty Street Economics Blog

June 29, 2016

Is Bitcoin Really Frictionless?

Liberty Street Economics Blog

March 23, 2016

The payment system benefits of high reserve balances

Journal of Payments Strategy and Systems

Spring 2016

Swimming

The City Mile 2026 (1650Y Free)

February 22, 2026

22:48.11

Lake Tahoe True Width

August 5, 2025