Cannot run remote build, got SIGABRT on some child process

I’m trying to use remote builder and faced with strange error when running nix-build default.nix -j0 --builders 'root@nix-builder' on this simple derivation:

  pkgs = import <nixpkgs> {};
in pkgs.stdenv.mkDerivation {
  pname = "software";
  version = "0.0.1";
  phases = "buildPhase installPhase";
  buildPhase = ''
    echo a > a
  installPhase = ''
    mkdir -p $out
    mv a $out/a

The issue is that I got following error:

[root@nixos:~]# nix-build default.nix -j0 --builders 'root@nix-builder'
these derivations will be built:
these paths will be fetched (46.74 MiB download, 213.60 MiB unpacked):
copying path '/nix/store/5wvf6qy2pjijd93n4dn6vvbn45ij9fdr-linux-headers-5.12' from ''...
building '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv' on 'ssh://root@nix-builder'...
copying 1 paths...
builder for '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv' failed due to signal 6 (Aborted)
error: build of '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv' failed

Verbose build didn’t say much to me:

[root@nixos:~]# nix-build default.nix -vvvvvv -j0 --builders 'root@nix-builder'
querying remote host 'root@nix-builder.' for info on '/nix/store/bdmdbc9xx0c2k8a2w0vxxn90gqp171cl-software-0.0.1'
waiting for children
building of '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv': read 214 bytes
waiting for children
building of '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv': got EOF
building of '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv': woken up
building of '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv': build done
killing process 69454
builder process for '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv' finished
builder for '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv' failed due to signal 6 (Aborted)
lock released on '/nix/store/bdmdbc9xx0c2k8a2w0vxxn90gqp171cl-software-0.0.1.lock'
building of '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv': done
building of '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv': goal destroyed
error: build of '/nix/store/p8qjdkqks6vfwdjrjh4idhm38jqqb5ch-software-0.0.1.drv' failed

According to strace -f nix-build ... I see that one of the child processes indeed get SIGABRT but I cannot understand why. How can I debug this issue?