Bunch of error after update to Nix 2.3.7

After update from nix2.0 to 2.37, I cannot install, uninstall, or update anything now.
How can I repair it?

nix-env -iA nixpkgs.nix
warning: unknown setting ‘signed-binary-caches’
error: attribute ‘nixpkgs’ in selection path ‘nixpkgs.nix’ not found

nixos-rebuild boot --upgrade
warning: unknown setting ‘signed-binary-caches’
importing path ‘/nix/store/77qh695s50b3cd52a70v38m1dr0l5nwc-nixos-17.09’
error: imported archive of ‘/nix/store/77qh695s50b3cd52a70v38m1dr0l5nwc-nixos-17.09’ lacks a signature

nix-env --uninstall streamlink
warning: unknown setting ‘signed-binary-caches’
uninstalling ‘streamlink-0.8.1’
building path(s) ‘/nix/store/zxwhjd98955j8jclff3gas6pv7qvsn21-user-environment’
error: unsupported builtin function ‘buildenv’
builder for ‘/nix/store/w1acp24j2x4nsf18kdj1kwh6yh3hc5ph-user-environment.drv’ failed with exit code 1
error: build of ‘/nix/store/w1acp24j2x4nsf18kdj1kwh6yh3hc5ph-user-environment.drv’ failed

Here is nix-info results.

  • system: "x86_64-linux"
  • host os: Linux 4.9.86, NixOS, 17.09.3269.14f9ee66e63 (Hummingbird)
  • multi-user?: yes
  • sandbox: no
    warning: unknown setting ‘signed-binary-caches’
  • version: nix-env (Nix) 2.3.7
    warning: unknown setting ‘signed-binary-caches’
  • channels(usr): ""
    warning: unknown setting ‘signed-binary-caches’
  • channels(root): "nixos-17.09.3269.14f9ee66e63"
    warning: unknown setting ‘signed-binary-caches’
  • nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs