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{
  lib,
  config,
  ...
}: {
  programs.firejail.enable = true;
  security.auditd.enable = true;
  security.audit.enable = true;
  security.audit.rules = [
    "-a exit,always -F arch=b64 -S execve"
  ];

  # https://source.android.com/docs/security/test/scudo
  # environment.memoryAllocator.provider = "scudo";
  # environment.variables.SCUDO_OPTIONS = "ZeroContents=1";

  security.lockKernelModules = true;
  security.protectKernelImage = true;
  security.allowSimultaneousMultithreading = false;
  security.forcePageTableIsolation = true;

  security.unprivilegedUsernsClone = config.virtualisation.containers.enable;

  security.virtualisation.flushL1DataCache = "always";

  security.apparmor.enable = true;
  security.apparmor.killUnconfinedConfinables = true;

  # Restrict ptrace() usage to processes with a pre-defined relationship
  # (e.g., parent/child)
  boot.kernel.sysctl."kernel.yama.ptrace_scope" = lib.mkOverride 500 1;

  # Hide kptrs even for processes with CAP_SYSLOG
  boot.kernel.sysctl."kernel.kptr_restrict" = lib.mkOverride 500 2;

  # Disable bpf() JIT (to eliminate spray attacks)
  boot.kernel.sysctl."net.core.bpf_jit_enable" = false;

  # Disable ftrace debugging
  boot.kernel.sysctl."kernel.ftrace_enabled" = false;

  # Enable strict reverse path filtering (that is, do not attempt to route
  # packets that "obviously" do not belong to the iface's network; dropped
  # packets are logged as martians).
  boot.kernel.sysctl."net.ipv4.conf.all.log_martians" = true;
  boot.kernel.sysctl."net.ipv4.conf.all.rp_filter" = "1";
  boot.kernel.sysctl."net.ipv4.conf.default.log_martians" = true;
  boot.kernel.sysctl."net.ipv4.conf.default.rp_filter" = "1";

  # Ignore broadcast ICMP (mitigate SMURF)
  boot.kernel.sysctl."net.ipv4.icmp_echo_ignore_broadcasts" = true;

  # Ignore incoming ICMP redirects (note: default is needed to ensure that the
  # setting is applied to interfaces added after the sysctls are set)
  boot.kernel.sysctl."net.ipv4.conf.all.accept_redirects" = false;
  boot.kernel.sysctl."net.ipv4.conf.all.secure_redirects" = false;
  boot.kernel.sysctl."net.ipv4.conf.default.accept_redirects" = false;
  boot.kernel.sysctl."net.ipv4.conf.default.secure_redirects" = false;
  boot.kernel.sysctl."net.ipv6.conf.all.accept_redirects" = false;
  boot.kernel.sysctl."net.ipv6.conf.default.accept_redirects" = false;

  # Ignore outgoing ICMP redirects (this is ipv4 only)
  boot.kernel.sysctl."net.ipv4.conf.all.send_redirects" = false;
  boot.kernel.sysctl."net.ipv4.conf.default.send_redirects" = false;

  security.chromiumSuidSandbox.enable = true;

  security.sudo.execWheelOnly = true;
  security.sudo.extraConfig = "Defaults        lecture = never";

  environment.defaultPackages = lib.mkForce [];
}