CyanogenMod is based on the Android Open Source Project with extra contributions from many people within the Android community. It can be used without any need to have any Google application installed. Linked below is a package that has come from another Android project that restore the Google parts. CyanogenMod does still include various hardware-specific code, which is also slowly being open-sourced anyway.

All the source code for CyanogenMod is available in the CyanogenMod Github repo. And if you would like to contribute to CyanogenMod, please visit out Gerrit Code Review.
INSTALLATION
XDA:DevDB Information
[ROM][UNOFFICIAL][LP5.1.1] CyanogenMod 12.1 Galaxy Tab 4 8.0 [SM-T330], ROM for the Samsung Galaxy Tab 4
Contributors
sub77
Source Code: https://github.com/sub77
ROM OS Version: 5.1.x Lollipop
ROM Kernel: Linux 3.10.x
Version Information
Status: Testing
Created 2015-04-30
Last Updated 2015-04-30

All the source code for CyanogenMod is available in the CyanogenMod Github repo. And if you would like to contribute to CyanogenMod, please visit out Gerrit Code Review.
INSTALLATION
XDA:DevDB Information
[ROM][UNOFFICIAL][LP5.1.1] CyanogenMod 12.1 Galaxy Tab 4 8.0 [SM-T330], ROM for the Samsung Galaxy Tab 4
Contributors
sub77
Source Code: https://github.com/sub77
ROM OS Version: 5.1.x Lollipop
ROM Kernel: Linux 3.10.x
Version Information
Status: Testing
Created 2015-04-30
Last Updated 2015-04-30
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