
Time-Travel Debugging for JavaScript/Node.js - ratancs
https://www.microsoft.com/en-us/research/publication/time-travel-debugging-javascriptnode-js/
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hitr
When I was working at Microsoft ,we used Time travel tracing extensively to
find out bugs in asp.net,IIS and many other server side technologies where you
cannot debug live.You can capture the trace from the live process while
reproducing the isuue.Move it your local machine and debug yourself to
oblivion :) .Imagine you use gdb/windbg and you can go back or forth from any
breakpoints ,check the state of stack ,any variables etc.

But these tools were internal and not available outside.It did require good
assembly knowledge and always condidered cool by everyone else because not
everyone knew or mastered it.I always thought that Microsoft should open
source or at least release it outside .

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realharo
On Linux, there is [http://rr-project.org/](http://rr-project.org/)

Or a commercial, more polished product [http://undo.io/](http://undo.io/)

Other environments, like JVM also have such tools (e.g.
[http://chrononsystems.com/](http://chrononsystems.com/)).

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VeejayRampay
Note that this is only usable with Node ChakraCore. I just tried downloading
Visual Studio Core Insiders to test it, but the feature isn't available since
I'm using the run of the mill Node / V8.

If anyone knows if such a feature will be available with Node / V8 in the
future as well, please do tell.

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emj
Nice results getting perfomance hit and memory bloatage down so much.
Apparently it's already in Visual Studio Code Inside Build:
[http://www.mattzeunert.com/2016/12/22/vs-code-time-travel-
de...](http://www.mattzeunert.com/2016/12/22/vs-code-time-travel-
debugging.html)

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camus2
Has anybody here tried node-chakracore in production? I'm strongly interested
in moving from V8.

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mmcwilliams
Just curious, what compels you to move off V8? I'm always interested in
scrutinizing the platforms I use.

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axemclion
You can use this same tech to do time travel debugging in React Native apps -
[http://blog.nparashuram.com/2016/08/time-travel-debugging-
wi...](http://blog.nparashuram.com/2016/08/time-travel-debugging-with-
reactnative.html)

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jazoom
September 2016

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JBiserkov
Time-travel to August 2016 and "wait for it" :-)

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jiyinyiyong
I would prefer calling it "Time tracing debugger", it not traveling as Bret
Victor told.

