Yes, that repository belongs to the Github of ZCash foundation and ZCash foundation is made up of ZCash developers. It should be safe.
Thank !
And which addresses can I use, T or Z?
I used to read that using Z-addresses can cause problems.
Don't use Z addresses until and unless you really want to keep your balance private. Z-addresses are fairly difficult to handle.
Therein lies the problem, having both T and Z addresses:
(a) complex and error-prone
(b) kills privacy because people don't use stealth addresses
Not only that, these jokers forced you to move all your coins to T for sapling...
Long story short... ZEC has zero privacy = chainanalysis will expose everything...
ycash does not address any of this... sell into pump.