https://www.sourcetrail.com/ https://www.sourcetrail.com/ is also a good source code explorer. There is also the much older https://scitools.com/ https://scito

https://www.sourcetrail.com/ https://www.sourcetrail.com/ is also a good source code explorer. There is also the much older https://scitools.com/ https://scitools.com/ but it costs a fortune.