hi @aram, thxs for considering my issue.
Oh, sorry i was in ubuntu 16, i will try ubuntu 20 (from Microsoft Store)
-> some issue with rust install same as https://github.com/rust-lang/rustup/issues/2293
-> resolved by https://github.com/microsoft/WSL/issues/4898#issuecomment-633771079
then running pack_install(terminus_store_prolog).
i encountered this issue swi-prolog.discourse.group/t/www-swi-prolog-org-goes-https/811/3
now i got this one
$ ./start.pl
[...]
ERROR: Run TerminusDB using SWI-Prolog version 8.1.11 or 8.1.10 or 8.0.3, you are on 7.6.4
so i upgraded h ttps://wwu-pi .github.io /tutorials/lectures/lsp/010_install_swi_prolog.html
(as new contrib i can’t post more than 2 links 
I continue 
prolog 8.2.0 was installed but
david@smag:~/terminus-server$ swipl --version
SWI-Prolog version 8.2.0 for x86_64-linux
david@smag:~/terminus-server$ ./start.pl
ERROR: /home/david/terminus-server/library/triplestore.pl:14:
ERROR: source_sink `library(terminus_store)' does not exist
Warning: /home/david/terminus-server/library/triplestore.pl:14:
Warning: Goal (directive) failed: triplestore:reexport(library(terminus_store),except([create_named_graph/3,open_named_graph/3]))
% Started server at http://localhost:6363/
ERROR: /home/david/terminus-server/start.pl:21: Initialization goal raised exception:
ERROR: Unknown procedure: triplestore:open_directory_store/2
ERROR: In:
ERROR: [36] triplestore:open_directory_store('/home/david/terminus-server/storage/db/',_2564)
ERROR: [35] '<meta-call>'((triplestore: ...,triplestore: ...)) <foreign>
ERROR: [34] triplestore:db_path('/home/david/terminus-server/storage/db/'),triplestore:(...,...) at /usr/lib/swi-prolog/boot/init.pl:322
ERROR: [33] <meta call>
ERROR: [32] with_mutex(sync_storage,(db_path('/home/david/terminus-server/storage/db/'),...,...)) <foreign>
ERROR: [29] '<meta-call>'(server:(sync_backing_store,...)) <foreign>
ERROR: [28] setup_call_catcher_cleanup(server:http_handler(...,busy_loading,...),server:(sync_backing_store,...),_2816,server:http_delete_handler(...)) at /usr/lib/swi-prolog/boot/init.pl:564
ERROR: [26] server:server([]) at /home/david/terminus-server/library/server.pl:50
ERROR: [25] main([]) at /home/david/terminus-server/start.pl:159
ERROR: [24] catch(user:main([]),_2952,user:throw(_2974)) at /usr/lib/swi-prolog/boot/init.pl:482
ERROR: [23] catch_with_backtrace(user:main([]),_3006,user:throw(_3028)) at /usr/lib/swi-prolog/boot/init.pl:532
ERROR:
ERROR: Note: some frames are missing due to last-call optimization.
ERROR: Re-run your program in debug mode (:- debug.) to get more detail.
ERROR: Run TerminusDB using SWI-Prolog version 8.1.11 or 8.1.10 or 8.0.3, you are on 8.2.0
and I can’t install 8.1.11 as needed :
david@smag:~/terminus-server$ sudo apt list swi-prolog
Listing... Done
swi-prolog/focal 8.2.0-4-gaf1ad4bf8-focalppa2 amd64
N: There is 1 additional version. Please use the '-a' switch to see it
david@smag:~/terminus-server$ sudo apt list swi-prolog -a
Listing... Done
swi-prolog/focal 8.2.0-4-gaf1ad4bf8-focalppa2 amd64
swi-prolog/focal 7.6.4+dfsg-2ubuntu2 amd64
david@smag:~/terminus-server$
Any idea ? Do you plan to migrate to Prolog 8.2.0 ?
which must i install ? http s://launchpad.net/~swi-prolog/+archive/ubuntu/devel