source.markdown

% Managing Projects with Nix % サニエ エリック % 2017年2月24日 - Tokyo NixOS Meetup

Foreword

• Get a copy of the presentation repo to play with the code:

  $ git clone https://github.com/Tokyo-NixOS/presentations.git

Agenda

• News
• Managing Projects with Nix

News

• Docker Nix Builder
• Nix Bundle
• OSC 2017 Tokyo Spring
• Haskell -> 8.0.2
• Python 3 as default?
• 17.03

Managing projects with Nix

• Overview
  • Preparing a dev environment
  • Building with Nix
  • Build web projects
  • Making tests

Dev environments

• nix-shell can be used create custom environments

Nix-shell

• Nix shell is a tool to enter in a nix build environment

• Can be used to create ad-hoc environments with custom packages

  $ nix-shell -p elixir

• Clean shells can spawned by using the --pure flag

Nix-shell expressions

• A shell.nix can be used to provide an environment
• Declares build dependencies
• Can provide other programs (editors, tools, ...)

Example

• 2017/02/examples/binserver/shell.nix

Building a project

• Derivation files are used for building projects
• See last month slides and examples for more details
  • 2017/01/source.markdown

Example

• 2017/02/examples/binserver/default.nix
• 2017/02/examples/binserver/derivation.nix

Derivations limitations

• Derivations build packages
• ... but cannot manage global state (host configuration, ports, hosts, ...)

Containers

• NixOS + Nix containers can manage global state in a deterministic way
• Containers require to use modules, so ...

Modules

• Modules are the foundation of NixOS
• They are a declarative and determistic wa to manage OS configuration
• Easy to write and manage

Example

• 2017/02/examples/binserver/module.nix

Nix tests

• Nix tests are the way NixOS modules are tested
• Example
• Nix tests are:
  • Logical definition of machine(s)
  • Test script
• Nix tests are run in a clean virtual environment

Example

• 2017/02/examples/binserver/test.nix

Next meetup

• Hydra