Mattan Griffel

CEO at Y Combinator-backed www.onemonth.com, growth hacker, and online learning expert


How to never forget anything ever again

My exploration of Spaced Repetition


Two years ago I was having breakfast with a man who was purportedly the most…


How to Develop a Daily Writing Habit

A Guide to Keeping Your New Year‘s Resolution


One of my New Year’s resolutions for 2014 was to write daily. I’m happy to…


Why Our Site Went Down on Cyber Monday

A.K.A. What’s a DoS Attack?


“Everybody has a plan until they get punched in the face.” — Mike Tyson

Email overload? Read this.

Stop wasting time on email. Here’s how.

Have you ever spent an entire day checking your email, just to find that you have more email at the end…

Publications edited by Mattan Griffel

A collection of stories written by a small group of friends. It works roughly like this: we take turns sending each other a first sentence or two and then the other person writes the rest of the story. There is no editing. It’s written improv. 

Want to write more? So do we. So we designed a free 30-day series of writing prompts so we could play around with stories, ideas, and essays for a month. These are some of the stories that came from our month-long community experiment.


The Value of Y Combinator & Accelerators

From the guys at One Month


A lot of people ask me about Y Combinator, so I’m going to write about it. The most common…


My open source brain data

I want to share an experiment I’ve been doing on and off for the past year or so.

I’ve been doing exercises on Lumosity and recording the scores as well as some meta-data in Google docs to track how certain things affect my mental performance.


Things I can worry about in the morning


There was a night last summer where I was having a lot of trouble sleeping. I was out at Y Combinator working on what would become One Month, and it…


I’ll have a diet code, please

What people really mean when they say “I want to learn to code”


There are two important things to know about coding education:


The Innovator’s Dilemma In Education

AKA “Online things aren’t as good.”


It goes something like this:


How to never forget anything ever again

My exploration of Spaced Repetition


Two years ago I was having breakfast with a man who was purportedly the most…


How to get a busy person to respond to your email

5 rules for good email etiquette 


Some days I get hundreds of emails a day. It really sucks.