tl;dr: On 18nov, I gave my notice to Brendan and Bob that I will be leaving Mozilla, and sent an email internally at Mozilla on 26nov. I’m here until 31dec2013. Thats a lot of notice, yet feels right – its important to me that this is a smooth stable transition.

After they got over the shock, the RelEng team is stepping up wonderfully. Its great to see them all pitching in, sharing out the workload. They will do well. Obviously, at times like this, there are lots of details to transition, so please be patient and understanding with catlee, coop, hwine and bmoss. I have high confidence this transition will continue to go smoothly.

In writing this post, I realized I’ve been here 6.5 years, so thought people might find the following changes interesting:

1) How quickly can Mozilla ship a zero-day security release?
was: 4-6 weeks
now: 11 hours

2) How long to ship a “new feature” release?
was: 12-18 months
now: 12 weeks

3) How many checkins per day?
was: ~15 per day
now: 350-400 per day (peak 443 per day)

4) Mozilla hired more developers
increased number of developers x8
increased number of checkins x21
The point here being that the infrastructure improved faster then Mozilla could hire developers.

5) Mozilla added mobile+b2g:
was: desktop only
now: desktop + mobile + phoneOS – many of which ship from the *exact* same changeset

6) updated tools
was: cvs
now: hg *and* git (aside, I don’t know any other organization that ships product from two *different* source-code revision systems.)

7) Lifespan of human Release Engineers
was 6-12 months
now: two-losses-in-6-years (3 including me)
This team stability allowed people to focus on larger, longer term, improvements – something new hires generally cant do while learning how to keep the lights on.

This is the best infrastructure and team in the software industry that I know of – if anyone reading this knows of better, please introduce me! (Disclaimer: there’s a big difference between people who update website(s) vs people who ship software that gets installed on desktop or mobile clients… or even entire phoneOS!)

Literally, Release Engineering is a force multiplier for Mozilla – this infrastructure allows us to work with, and compete against, much bigger companies. As a organization, we now have business opportunities that were previously just not possible.

Finally, I want to say thanks:

• I’ve been here longer then a few of my bosses. Thanks to bmoss for his council and support over the last couple of years.
• Thanks to Debbie Cohen for making LEAD happen – causing organizational change is big and scary, I know its impacted many of us here, including me.
• Thanks to John Lilly and Mike Schroepfer (“schrep”) – for allowing me to prove there was another, better, way to ship software. Never mind that it hadn’t been done before. And thanks to aki, armenzg, bhearsum, catlee, coop, hwine, jhopkins, jlund, joey, jwood, kmoir, mgerva, mshal, nthomas, pmoore, rail, sbruno, for building it, even when it sounded crazy or hadn’t been done before.
• Finally, thanks to Brendan Eich, Mitchell Baker, and Mozilla – for making the “people’s browser” a reality… putting humans first. Mozilla ships all 90+ locales, even Khmer, all OS, same code, same fixes… all at the same time… because we believe all humans are equal. It’s a living example of the “we work for mankind, not for the man” mindset here, and is something I remain super proud to have been a part of.

take care
John.

http://oduinn.com/blog/2013/12/11/on-leaving-mozilla/