I am trying to install Liquidity on a VM with Ubuntu 18.04.2 LTS following this instruction http://www.liquidity-lang.org/doc/installation/index.html . Everything goes well until stage 4: Install Liquidity dependencies: make build-deps . After entering this command, I get the error message:

opam install . --deps-only [WARNING] Running as root is not recommended [WARNING] Failed checks on liquidity package definition from source at git+file:///root/liquidity#next: error 57: Synopsis and description must not be both empty The following actions will be performed: ∗ install conf-libcurl 1 ∗ install conf-libsodium 1 ∗ install ocurl 0.8.2 ∗ install sodium 0.6.0 ===== ∗ 4 ===== Do you want to continue? [Y/n] y <><> Gathering sources ><><><><><><><><><><><><><><><><><><><><><><><><><><><><> [ocurl.0.8.2] found in cache [sodium.0.6.0] found in cache <><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><> [ERROR] The compilation of conf-libcurl failed at "/root/.opam/opam-init/hooks/sandbox.sh build pkg-config libcurl". [ERROR] The compilation of conf-libsodium failed at "/root/.opam/opam-init/hooks/sandbox.sh build pkg-config libsodium". #=== ERROR while compiling conf-libsodium.1 ===================================# # context 2.0.4 | linux/x86_64 | ocaml-base-compiler.4.06.1 | https://opam.ocaml.org/#c7c0bde9 # path ~/.opam/liquidity/.opam-switch/build/conf-libsodium.1 # command ~/.opam/opam-init/hooks/sandbox.sh build pkg-config libsodium # exit-code 1 # env-file ~/.opam/log/conf-libsodium-1310-d2d111.env # output-file ~/.opam/log/conf-libsodium-1310-d2d111.out #=== ERROR while compiling conf-libcurl.1 =====================================# # context 2.0.4 | linux/x86_64 | ocaml-base-compiler.4.06.1 | https://opam.ocaml.org/#c7c0bde9 # path ~/.opam/liquidity/.opam-switch/build/conf-libcurl.1 # command ~/.opam/opam-init/hooks/sandbox.sh build pkg-config libcurl # exit-code 1 # env-file ~/.opam/log/conf-libcurl-1310-c61e7b.env # output-file ~/.opam/log/conf-libcurl-1310-c61e7b.out <><> Error report <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> ┌─ The following actions failed │ λ build conf-libcurl 1 │ λ build conf-libsodium 1 └─ ╶─ No changes have been performed The packages you requested declare the following system dependencies. Please make sure they are installed before retrying: libcurl4-gnutls-dev libsodium-dev Makefile:61: recipe for target 'build-deps' failed make: *** [build-deps] Error 31 root@ubuntu-s-2vcpu-2gb-fra1-01:~/liquidity#

I'm not a very experienced Linux user. What am I doing wrong? Please, help