[paperwork]

I'm a big fan of Chronon[1] for Java. Run a program and record everything about it. Use the same eclipse debug interface as always, but also have the ability to re-wind to an earlier point. Check out the state of any variable in the code, at any time. It knows about threads, can reproduce inputs/outputs, etc.

I believe it is now integrated with intellij as well.

No connection to the product, other than the fact that I paid for it. Unfortunately it doesn't seem to be very well marketed.

From what I recall (last few months I've been away from Java), you can't modify anything and re-run it (which Elm's debugger seems to be able to do).

[1]http://chrononsystems.com/

[mateuszf]

I'm not sure about it, but AFAIR it comes for free for Intellij Idea Ultimate users.

[crazysaem]

Yes, it was added in 13.1. And only in the Ultimate version, as you mentioned. http://blog.jetbrains.com/idea/2014/03/try-chronon-debugger-...

[mgkimsal]

Would love for it to support Groovy, and/or there to be something similar for PHP.

[girvo]

Codebug for the Mac isn't time travelling, but coupled with Xdebug and some break points it'll drop you into an interactive console at various points you want to explore. I'm hooked :)

[mgkimsal]

phpstorm and intellij are enough for me already, but would love the 'time traveling' aspect (I think of it more like a code DVR).

chronon works OK for java, but I do grails work, and the groovy metaprogramming stuff isn't supported in chronon.