# Processing 3 and 4 Compatibility
**URL:** https://discourse.processing.org/t/processing-3-and-4-compatibility/32446
**Category:** Processing
**Created:** [September 27, 2021, 4:54pm UTC](https://discourse.processing.org/t/processing-3-and-4-compatibility/32446 "2021-09-27T16:54:21Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@reProcessing](https://discourse.processing.org/u/reProcessing)
#### Post date: [September 27, 2021, 4:54pm UTC](https://discourse.processing.org/t/processing-3-and-4-compatibility/32446/1 "2021-09-27T16:54:21Z")
For the last few months I’ve been cobbling together a really cool system in Processing 3. In fact it is so cool I really don’t know what its ultimate purpose or capabilities will be. A first for me!
I’d like to install the new version but I’m not certain I want (or need) to completely move to it yet. I read the information about what has changed and was most concerned I guess about the new version of Java running with the old version.
Is it possible to run both version 3 and 4 of Processing on the same W10(64) box? I’d guess yes but don’t want to commit just yet and don’t want to hose up my working system right now : )
Thanks in advance!
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### Author:  [@glv](https://discourse.processing.org/u/glv)
#### Post date: [September 27, 2021, 6:28pm UTC](https://discourse.processing.org/t/processing-3-and-4-compatibility/32446/2 "2021-09-27T18:28:23Z")
Hello,
See this topic:
> [@Can I safely install both Processing 4 and Processing 3.5.4?](https://discourse.processing.org/t/can-i-safely-install-both-processing-4-and-processing-3-5-4/31700/2):
>
> Hello, I have both installed. On startup: slight_smile
`:)`
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### Author:  [@reProcessing](https://discourse.processing.org/u/reProcessing)
#### Post date: [September 28, 2021, 3:34pm UTC](https://discourse.processing.org/t/processing-3-and-4-compatibility/32446/3 "2021-09-28T15:34:35Z")
Thanks for the answer glv! Don’t fault me if I’m still worried : (
I’m now satisfied the two Ps can coexist without issues mainly because the install is so clean; doesn’t do much but lay down files. Nice! And just keeping sketches separated should be all you need with that.
Now my questions and hesitation relate more to what happens if a supporting Processing or contributed library fails, or the underlying Javas can hose each other up, or if any input and/or output options for various image/audio/video/hardware handling fail, etc.
One of my sketches uses these libraries right now (and I need to add other support to it): netP5, oscP5, controlP5, processing.serial, processing.sound, themidibus, ch.bildspur.artnet, [processing.io](http://processing.io), and [processing.net](http://processing.net). I use cameras, mics, speakers, and a microcontroller via serial support. This is what scares me : )
Worse yet my brain went down this track … What if a contributed library provider’s old code won’t work in the “Next” version? Or what if a new library won’t support the “old” version … which your sketch can only be run under? What then : O
Processing is such a great tool I have to assume these scenarios have been well thought through to avoid issues. Big plus: this is V4 so this has happened before. I’ve only used version 3.
Guess I will create a restore point, install the new version (aborted my initial attempt when a critical component was flagged as a trojan), and run a simple test (with fingers crossed : )
If you have been sketching heavily for a while using lots of libraries and such … think I should be worried?
Thanks in advance!