problems with building ada-mode

[Bernardo]

Greetings,

A total Ada newb here, having problems with building ada-mode.

Running:
 Emacs 28.0.50
 ada-mode-7.0.1
 gnat-8 (having the same problem with gnat-7)
 on Debian 10 (buster)

Getting this error when building ada-mode:

$ ./build.sh 
HAVE_GNATCOLL_XREF=no
ada_mode_wisi_parse.gpr:21:06: unknown project file: "gnatcoll"
ada_mode_wisi_parse.gpr:22:06: unknown project file: "gnatcoll_sqlite"
ada_mode_wisi_parse.gpr:23:06: unknown project file: "gnat_util"
wisi.gpr:20:06: unknown project file: "gnatcoll"
wisi.gpr:20:06: imported by "/home/.../elisp/Package/wisi-3.0.1/wisi.gpr"
wisi.gpr:20:06: imported by 
"/home/.../elisp/Package/ada-mode-7.0.1/ada_mode_wisi_parse.gpr"
gprbuild: "ada_mode_wisi_parse.gpr" processing failed

As I don't know what gnatcoll is and there isn't much in Debian
collection of packages, tried cloning and building
https://github.com/AdaCore/gnatcoll-core but with not much success
either:

   $ make
   gprbuild -p -m --target=x86_64-linux-gnu  -j0 -XGNATCOLL_MMAP=yes 
-XGNATCOLL_MADVISE=yes -XGNATCOLL_VERSION=0.0 -XGNATCOLL_OS=unix -XBUILD=PROD  
-XLIBRARY_TYPE=static -XXMLADA_BUILD=static -XGPR_BUILD=static \
        -XGNATCOLL_MMAP=yes -XGNATCOLL_MADVISE=yes -XGNATCOLL_VERSION=0.0 
-XGNATCOLL_OS=unix -XBUILD=PROD gnatcoll.gpr
   Setup
      [mkdir]        object directory for project GnatColl
      [mkdir]        library directory for project GnatColl
   gnatcoll.gpr:24:06: unknown project file: "gpr"
   gprbuild: "gnatcoll.gpr" processing failed
   make: *** [Makefile:128: build-static] Error 4


Any ideas what am i missing here?