danbst

# this example adds an option `.tomcatProxy` in namespace
#   services.nginx.virtualHosts.*.locations.*
# that acts as alternative to specifying actual nginx config in .extraConfig
#
# execute with
/*
  cat $(grep -o "/nix/store/[a-z0-9]*-nginx.conf" \
        $(NIX_PATH=nixos-config=./example.nix:$NIX_PATH \
          nix-build --no-out-link -E '
            with import <nixpkgs/nixos> {};

rofrol

Elm best practices

Style guide

• http://package.elm-lang.org/help/design-guidelines
• http://elm-lang.org/docs/style-guide
• https://github.com/NoRedInk/elm-style-guide
• https://gist.github.com/laszlopandy/c3bf56b6f87f71303c9f
• https://github.com/ohanhi/elm-style-guide

FRidh

Python on Nix infrastructure

Introduction

Python is used throughout Nixpkgs. We use it for certain scripts, we provide Python libraries, and we provide applications. There are several methods on how to use Python on Nix, each with their pros and cons. An overview of all issues with the current Python infrastructure on Nix is available in the placeholder issue 1819.

Goal

FRidh

Nix guides

Currently the following guides exist:

1. Nix reference guide
2. NixOS reference guide
3. Hydra reference guide
4. Nixpkgs guide

as well as a (mostly outdated) read-only wiki.

edolstra

General notes

• nix-channel and ~/.nix-defexpr are gone. We'll use $NIX_PATH (or user environment specific overrides configured via nix set-path) to look up packages. Since $NIX_PATH supports URLs nowadays, this removes the need for channels: you can just set $NIX_PATH to e.g. https://nixos.org/channels/nixos-15.09/nixexprs.tar.xz and stay up to date automatically.

• By default, packages are selected by attribute name, rather than the name attribute. Thus nix install hello is basically equivalent to nix-env -iA hello. The attribute name is recorded in the user environment manifest and used in upgrades. Thus (at least by default) hello won't be upgraded to helloVariant.

  @vcunat suggested making this an arbitrary Nix expression rather than an attrpath, e.g. firefox.override { enableFoo = true; }. However, such an expression would not have a key in the user environment, unlike an attrpath. Better to require an explicit flag for this.

TBD: How to deal with search path clashes.

FRidh

Nix cheatsheet

Maintenance

Updating package channels is done with sudo nix-channel --update

Rebuilding the main system is done with sudo nixos-rebuild switch and upgrading with

grugq

Operational PGP

This is a guide on how to email securely.

There are many guides on how to install and use PGP to encrypt email. This is not one of them. This is a guide on secure communication using email with PGP encryption. If you are not familiar with PGP, please read another guide first. If you are comfortable using PGP to encrypt and decrypt emails, this guide will raise your security to the next level.

ax3l

In general, check the crt/host_config.h file to find out which versions are supported. Sometimes it is possible to hack the requirements there to get some newer versions working, too :)

Thrust version can be found in $CUDA_ROOT/include/thrust/version.h.

Download Archives: https://developer.nvidia.com/cuda-toolkit-archive

Release notes for CUDA Toolkit (CTK):

• latest: https://docs.nvidia.com/cuda/cuda-toolkit-release-notes/index.html
• archive: https://docs.nvidia.com/cuda/archive/

rygorous

// float->half variants.
// by Fabian "ryg" Giesen.
//
// I hereby place this code in the public domain, as per the terms of the
// CC0 license:
//
//   https://creativecommons.org/publicdomain/zero/1.0/
//
// float_to_half_full: This is basically the ISPC stdlib code, except
// I preserve the sign of NaNs (any good reason not to?)