TOPICS

Things to write about.
Will probably converge towards nix pills.

Also think of this as cookbook/howto

- standalone shell (dash)
- isolated toolchain (paried glibc + gcc, without touching /usr/lib)
- nixcpp deps + final build.
- impure toplevel stuff. cacerts, .config/nix/nix.conf, NIX_PATH, overlays
- runtime vs buildtime references
- bootstrap: importing binaries as fixed-output derivations.
- bootstrap: invoking imported binaries (linux loader, RUNPATH, patchelf)
- bootstrap: shebangs. /bin/sh, CONFIG_SHELL
- bootstrap: popen, locales.
- bootstrap: isolated toolchain, redux: now from within sandboxed build.
- bootstrap: progressively scrubbing external references
- fetchurl vs builtins.fetchTarball
- make-stdenv, make-derivation. ability to override; supplying dependencies, hooks.
- runCommand, optionalAttrs, nix-shell support.  Also nxfs-shell
- nix-support/setup-hook, seutp.sh, unpackPhase/buildPhase etc,
  buildInputs[] vs initialPath[]
- problems with /dev/pts on ubuntu.
  - check status:
     $ cat /proc/sys/kernel/unprivileged_userns_clone
     $ cat /proc/sys/kernel/apparmor_restrict_unprivileged_userns

  - 1. or 2.
  1. building with sandbox disabled -- sketchy!
  2. drop ubuntu-specific userns restrictions.
    $ sudo sysctl -w kernel.apparmor_restrict_unprivileged_userns=0
    $ echo "kernel.apparmor_restrict_unprivileged_userns = 0" | sudo tee /etc/sysctl.d/99-nix-userns.conf

Once we have viable stdenv:
- buildEnv
- nix-shell

- stdenv-to-nix