Hi
I am not a Developer so i want an advice from you my friends
We are working on erpnext But there is some feature that we want it like create journal entry when we create invoice or bill not general ledger . and we want valuation rate in item to be dynamic updated when the costing method is average .
But our developer team said that is not a very good idea to change in the core of the erp so what is your opinion.
PS:WE want to make this customization because this is our vision to develop next and make it work with our client.
Ok… and this is from my own painful experience of modifying the core of a module.
If at all possible, try to work all of your modifications into a separate application in the frappe framework and then install that app to your erpnext server. I realize that working with complicated accounting functions in a separate app can be difficult (or maybe even impossible).
When you make changes to the core logic of one of the erpnext core modules, you are then forced into locking yourself and your client into whatever version you happened to modify forever.
Once the core has been altered, it will no longer revision up as updates become available. Every revision update would become an exercise in rewriting your modifications so they still work and the system does not lock-up.
I made extensive modifications to the POS module several versions ago and have suffered for it ever since. As new features and functions became available in later versions, I was not able to make those available to my client. They continue to use that modified version today and it is already almost 4 years old. Many new features have been added to ERPNext since that time.
Today (even as I type this) I am paying developers to figure out how to convert all of my clients old data to the newest v13 and eliminate all of my old customizations so that we can operate from a standard version again.
I tend to agree with your developers. I went against that advice once and will never make that same mistake again.
Just my experiences, and as always… Your mileage may vary! 
BKM
Auditors dont like Journal entries. Stick to ledger entries as much as you can. Journal entries are meant for rare manual correction. This is what I have learned during my interaction with client auditors like KPMG, EY etc.
For customization create an app so core remains intact. @bkm has wisely stated from years of experience.
1 Like
Thank you very much for sharing this . now I agree with you and with my team But if I tend to make from next a new erp system and made my version wil you keep the advise the same .
thank you very much:blush: