[tor-relays] Build problem

Hello,

I'm trying to build tor for from source on a x86 Debian stretch machine. I first installed all dependencies, but when I launch the "./configure" command I see the following error:

configure: WARNING: Unable to find liblzma. configure: WARNING: Unable to find libzstd

I installed, among the others liblzma-dev, lzma, libzstd-dev and zstd.

I'm working through ssh. What I'm doing wrong? Could It be caused by a wrong environment variables settings?

Cheers Gigi