JAMES LONG

is a developer & designer with over a decade of experience building large-scale applications. He created Prettier, the standard of JavaScript code formatting, led a long-term effort to port Firefox developer tools to React at Mozilla, is founder of Actual, and explores new ideas for programming through blog posts. He focuses on solving real problems for users with a great user experience. Let's work together

The personal finance system of your dreams

A product I've been working on for the last 3 years, launched in January, and working on scaling up to become my full-time income.

Check it out →

Prettier

Blink

• unwinder — an implementation of continuations
• transducers.js — a library for transformation of data
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May 26, 2020

At the very heart of Actual is a custom syncing engine. I'd like to talk about a PostgreSQL feature that enabled a 9-10x performance improvement.

May 6, 2020

This is a look at how I approach product design and all the considerations you need to think about. I explain some improvements in the recent version of Actual's budget table.

April 6, 2020

I'm joining Stripe.

February 11, 2020

Atomic commits are one of the most important properties of reliable software. Recently I improved the syncing layer of Actual using transactions, and I talk about why it's so important.

January 9, 2020

A deep dive into the relationship between growth and profit after my last post about profit forecasting.

CRDTs for Mortals

Go Ahead, Block the Main Thread

My History with Papers

A Prettier Printer

A Prettier Printer (lightning talk)

Debugging Your Debugger

Abstracting Just Enough

Cleaning the Tar: Using React within the Firefox Developer Tools

Unshackling JavaScript with Macros

High-Performance WebGL Apps with LLJS and asm.js