Sachin,
My apologies that your emails had gotten stuck in the queue. Please ensure you're subscribed to the list and sending messages to
mifos...@lists.sourceforge.net and not the Google Groups mirror which can't actually receive emails.
Concerning your questions, yes you are free to modify the software to suit clients needs and sell it commercially. Fineract is licensed under the permissive Apache License 2.0 which requires solely that you attribute that the software you are distributing is derived from an Apache-licensed project. The Mifos reference web UI on top of Fineract (community app or web app) is licensed under a slightly less permissive license, Mozilla Public License 2.0. MPL 2.0 is a weak copyleft license.
It is only classified as a weak copyleft license as it requires sharing a narrower set of code than a license like GPL as it enforces a file-based copyleft whereby upon distribution only original files under the license, if modified, need to be distributed under the MPL 2.0 as opposed to a copyleft like GPL which requires that if the code is modified and redistributed the entire program must be made available under the license. MPL 2.0 allows one to write code in new files which could then be kept proprietary or distributed under a different license. Only modifications to the original files or new files containing original licensed software need to be shared upon distribution.
MPL is a copyleft license that is easy to comply with. You must make the source code for any of your changes available under MPL, but you can combine the MPL software with proprietary code, as long as you keep the MPL code in separate files.
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