message: shell.nix: use named channel instead of tar.
  That way, the packages are always relative to the current distribution
  and doesn't age away.
  Update to Python 3.10
  While at it, add ccache for faster compile time turnarounds.
diff: # If you have nix installed, you may simply run `nix-shell`
  # in this repo, and have all dependencies ready in the new shell.
  -{pkgs ? import (builtins.fetchTarball {
  - # Descriptive name to make the store path easier to identify
  - name = "nixos-2021-11";
  - # Commit hash
  - url = "https://github.com/NixOS/nixpkgs/archive/refs/tags/21.11.tar.gz";
  - # Hash obtained using `nix-prefetch-url --unpack <url>`
  - sha256 = "162dywda2dvfj1248afxc45kcrg83appjd0nmdb541hl7rnncf02";
  -}) {}}:
  -
  -
  +{ pkgs ? import <nixpkgs> {} }:
  pkgs.mkShell {
  buildInputs = with pkgs;
  [
  + stdenv
  +
  antlr4
  cacert
  cmake
  @@ -23,15 +16,22 @@ pkgs.mkShell {
  gperftools
  jdk11
  lcov
  - libuuid
  libunwind
  + libuuid
  pkg-config
  - python3
  - python39Packages.orderedmultidict
  - python39Packages.psutil
  + python310
  + python310Packages.orderedmultidict
  + python310Packages.psutil
  swig
  tcl
  time
  zlib
  +
  + # Ease development
  + ccache
  ];
  + shellHook =
  + ''
  + export CMAKE_CXX_COMPILER_LAUNCHER=ccache
  + '';
  }
  