
Leaving Mozilla - curtis
http://robert.ocallahan.org/2016/03/leaving-mozilla.html
======
neves
I've never heard about rr [http://rr-project.org/](http://rr-project.org/)),
his tool to record program execution and debug it afterwards. The alleged 1.2x
slowdown in execution is negligible. The ability to reverse in time is almost
a nirvana. I'm sad I didn't have it when I used to program C++. Hope he
succeeds in his new endeavor. We'd all win big.

Does anyone knows of similar tools for Python and in-browser Javascript?

~~~
xigency
Sounds very similar Green Hills Software's TimeMachine for embedded
applications.

~~~
yitchelle
My thoughts were very similar to yours. In 1992, when I started out in
embedded on a Philips 8051 and debugging it was via an ICE and had direct
visibility and control of the 8051.

The ICE would be connected to a bonded out version of the 8051 and I was
almost able to capture every single clock cycle of 8051's execution. When I
hit a failure, I would just replay the trace and see what went wrong.

It looks like the folks on the big machines have caught up :-)

~~~
ArkyBeagle
I had access to a Huntsville Microsystems ICe that used a bog-standard - non-
bonded-out - 68008 in harness. I had scripting tools that would capture and
replay all the registers to back the machine up.

That HMI was a brilliant machine.

It's really the last debug tool I ever used besides AVR, PIC and one ARM JTAG
for doing BSP work.

------
joshmoz
I worked with Robert at Mozilla for many years. He might be the most talented
software engineer I've ever met, and he's a strong candidate for nicest person
as well. An absolute pleasure to work with. Mozilla will miss him dearly but
some other project (apparently rr) just got really lucky.

~~~
BrendanEich
rr is roc's baby ;-).

------
josteink
From reddit to answer the question some might pose ("who?"):

> One of Mozilla's most senior engineers who has worked on Mozilla projects as
> a contributor and employee for well over a decade particularly working in
> the graphics code and helping make native audio and video in the browser a
> reality.

[http://www.reddit.com/r/firefox/comments/48ix55/robert_ocall...](http://www.reddit.com/r/firefox/comments/48ix55/robert_ocallahan_is_leaving_mozilla/d0k5bay)

~~~
autotune
Great! Now how about the next question:

"Why?"

I suppose it's nice to know that he is a big deal but as someone who doesn't
follow mozilla religiously a little more background is always appreciated.

~~~
kibwen
Why is he leaving? That's covered in the OP: he wants to devote his full-time
attention to working on rr, a reversible debugger for native code that imposes
impressively low overhead, and possibly spin it into a startup.

~~~
jlebar
I think roc would give me a sly smile for pointing out that this doesn't
really answer the "why". It's what he's going to do after he leaves. Doesn't
quite answer _why_ he's leaving.

~~~
SkyMarshal
He just wants to build a startup out of some cool tech and get rich. There's
no conspiracy or dirty laundry here.

~~~
jwalden
My, cynical much? Seems to me that 10+ years at a non-profit, and choosing to
live in a place outside the traditional startup locations (New Zealand) with
fewer networking opportunities, might indicate fairly little interest in that
exact trajectory, for those exact reasons.

But what do I know, I'm just another ten-year Mozillian myself. And if or when
I leave, it'll also surely be to get filthy rich at a startup, right?

------
esaym
And for those that have no idea what rr is: [http://rr-
project.org/](http://rr-project.org/)

So no, he is not leaving for "rest and relaxation"

~~~
pmilot
To be fair, people also think "rest and relaxation" is amazing, and we
probably need to capture some of the value of this technology via a for-profit
company as well.

~~~
DonHopkins
I would pay to be able to time travel and replay my rest and relaxation!

------
vitno
Wow, it's the end of an era.

I wish him the best of luck. rr is really awesome and deserves even more
attention.

([http://rr-project.org/](http://rr-project.org/))

------
haberman
Regarding RR he says:

> we probably need to capture some of the value of this technology via a for-
> profit company

I hope this doesn't mean making it proprietary. I mean obviously a person gets
to decide how to best compensate themselves for the fruits of their labor. But
I've seen too many compelling technologies fail to achieve the impact they
could have because they were proprietary.

I mean, DTrace languishes despite being open-source, because it wasn't open-
source _enough_

~~~
mathattack
There's a decent market for selling consulting consulting services on top of
open source technology. Being the expert on applying an open source technology
to solve specific problems comes with a decent rate card.

~~~
davidbanham
You're still selling your labour rather than a product, though. It's possible
to be well off doing that, but basically impossible to become ludicrously
rich.

~~~
shmerl
He didn't say his goal is to become ludicrously rich. He said he has ideas
that Mozilla can't and shouldn't provide resources to realize, so some for
profit company would work better for it.

------
Arnavion
Thanks Robert for signing up for StackOverflow just to answer my question
[http://stackoverflow.com/q/34488237](http://stackoverflow.com/q/34488237)

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reledi
I'm not familiar with Robert or his work, but I quite liked this post. The
brevity and honesty was refreshing. I couldn't help but feel excited at the
end!

------
justinclift
Reverse debugging has been around for several years, but hasn't seemed to be
widely adopted. Which seems kind of unfortunate, as the concept of it looked
really useful.

Does rr make reverse debugging much easier than it's previously been in gdb or
something? :)

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chris_wot
I've tried to use rr on LibreOffice but had no luck whatsoever. :(

~~~
roca
Please file an rr issue. I've had it working in the past.

~~~
chris_wot
Just saw this - will do!

------
heavenlyhash
rr ([http://rr-project.org/](http://rr-project.org/)) is a piece of magic.
I've heard lots of people talk about using it in wild and awesome ways.

The second part of a magic trick is to connect it to your audience. Making
time-travel style debugging is... not easy, but possible. Making it _relevant_
to people, across languages and other conceptual domains, is hard.

If your next work is tackling this, good luck and godspeed :)

------
j0e1
Great work; Great song!

------
disordinary
Wonder if that's the end of Mozilla's only southern hemisphere office in
Auckland.

~~~
kibwen
I know of at least one other NZ Mozillian (Nick Cameron, on the Rust project)
but I'm not sure if he works remotely or at an office.

~~~
doublec
There were about ten NZ Mozilla employees when I worked there a year ago. Not
all at the Auckland office but there were plenty there to keep the office
utilized at the time.

------
yeukhon
If and only if there is a way to debug network traffic like I am stopping at
this router and hop to the next router.

------
st3v3r
"we probably need to capture some of the value of this technology via a for-
profit company"

Why?

~~~
garrettgrimsley
Perhaps they don't want to end up having to beg [0, 1] for donations so that
they can maintain a high quality application while also being able to afford
trivial niceties like "food" and "housing."

[0] [https://www.propublica.org/article/the-worlds-email-
encrypti...](https://www.propublica.org/article/the-worlds-email-encryption-
software-relies-on-one-guy-who-is-going-broke)

[1] [http://arstechnica.com/information-
technology/2014/04/tech-g...](http://arstechnica.com/information-
technology/2014/04/tech-giants-chastened-by-heartbleed-finally-agree-to-fund-
openssl/)

------
gansai
he just committed 7 hours ago.
[https://github.com/mozilla/rr/commit/ef7691ac8a25ec9767ba744...](https://github.com/mozilla/rr/commit/ef7691ac8a25ec9767ba7446e124bda45d192044)

~~~
geofft
Yes, per the blog post he plans to spend more time working on rr than he
thinks it's reasonable for Mozilla to have to support:

 _And now there 's rr. People think it's amazing, and it is, but we're only
scratching the surface of what could be done. I'm bursting with ideas, and
realizing them will require a lot of resources, resources that Mozilla cannot
and should not provide --- we probably need to capture some of the value of
this technology via a for-profit company. We can change the way people debug
software, and in its own way that may be as important as my Web platform work,
and it's work I desperately want to do._

