Index ¦ Archives ¦ Atom ¦ RSS

Why bootstrap?

Over the next few quarters, I'm going to focus my attention on Mozilla's experimentation platform. One of the first questions we need to answer is how we're going to calculate and report the necessary measures of variance. Any experimentation platform needs to be able to compare metrics between two groups …

SQL Style Guide

I'm happy to announce, we now have a SQL style guide. Check it out!

If you have any suggestions, feel free to file a PR or issue in the docs repository.

Many thanks to all who participated in the St. Mocli conversation and @mreid for the review!

PSA: Don't use approximate counts for trends

I got caught giving some bad advice this week, so I decided to share here as penance. TL;DR: Probabilistic counts are great, but they shouldn't be used everywhere.

Counting stuff is hard. We use probabilistic algorithms pretty frequently at Mozilla. For example, when trying to get user counts, we …

Don't make me code in your text box!

Whenever I start a new data project, my first step is rooting out any false assumptions I have about the data.

The key here is iterating quickly. My workflow looks like this: Code a little, plot the data, what do you see? Ah, outliers. Code a little, plot the data …

The 5 Stages of Experiment Analysis

I've been thinking about experimentation a lot recently. Our team is spending a lot of effort trying to make Firefox experimentation feel easy. But what happens after the experiment's been run? There's not a clear process for taking experimental data and turning it into a decision.

I noted the importance …

Asking Questions

Will posted a great article a couple weeks ago, Giving and Receiving Help at Mozilla. I have been meaning to write a similar article for a while now. His post finally pushed me over the edge.

Be sure to read Will's post first. The rest of this article is an …

Managing Someday-Maybe Projects with a CLI

I have a problem managing projects I'm interested in but don't have time for. For example, the CLI for generating slack alerts I posted about last year. Not really a priority, but helpful and not that complicated. I sat on that project for about a year before I could finally …

Removing Disqus

I'm removing Disqus from this blog. Disqus allowed readers to post comments on articles. I added it because it was easy to do, but I no longer think it's worth keeping.

If you'd like to share your thoughts, feel free to shoot me an email at harterrt on gmail. I …

Productivity Systems for Stress Management

Over the years, I've developed a pretty involved productivity system. It was originally based on Getting Things Done, but now it's grown to include the good bits from other systems. It's involved, but I love it.

I get a lot of comments, especially on the little black book I keep …

CLI for alerts via Slack

I finally got a chance to scratch an itch today.


When working with bigger ETL jobs, I frequently run into jobs that take hours to run. I usually either step away from the computer or work on something less important while the job runs. I don't have a good …

© Ryan T. Harter. Built using Pelican. Theme by Giulio Fidente on github.