index.js

  const gumshoe = require('gumshoe');

const mappings = {
  node: 'f898', // nf-mdi-nodejs
  react: 'e7ba', // nf-dev-react
  reason: 'e777', // nf-dev-haskell, sorry no Reason/Ocaml icon 😢
  ruby: 'e791', // nf-dev-ruby_rough
  rails: 'e73b', // nf-dev-ruby_on_rails
  elixir: 'e62d', // nf-custom-elixir
  clojure: 'e768', // nf-dev-clojure
  electron: 'e62e', // nf-custom-electron
  docker: 'f308', // nf-linux-docker
  android: 'f531', // nf-mdi-android
  ios: 'e711', // nf-dev-apple
  yeoman: 'e77a', // nf-dev-yeoman
  vue: 'fd42', // nf-mdi-vuejs
  puppeteer: 'f268', // nf-fa-chrome
  solidity: 'fcb9', // nf-mdi-currency_eth
};

const baseDir = process.cwd();

const rules = [
  {
    filename: 'bsconfig.json',
    exists: true,
    language: 'reason',
  },
  {
    filename: 'package.json',
    exists: true,
    grep: /react/,
    language: 'node',
    framework: 'react',
  },
  {
    filename: 'package.json',
    exists: true,
    grep: /electron/,
    language: 'node',
    framework: 'electron',
  },
  {
    filename: 'package.json',
    exists: true,
    grep: /"vue"/,
    language: 'node',
    framework: 'vue',
  },
  {
    filename: 'package.json',
    exists: true,
    grep: /yeoman-generator/,
    language: 'node',
    framework: 'yeoman',
  },
  {
    filename: 'package.json',
    exists: true,
    grep: /"puppeteer"/,
    language: 'node',
    framework: 'puppeteer',
  },
  {
    filename: 'package.json',
    exists: true,
    grep: /"solc"/,
    language: 'node',
    framework: 'solidity',
  },
  {
    filename: 'package.json',
    exists: true,
    language: 'node',
  },
  {
    filename: '*.xcodeproj',
    exists: true,
    language: 'ios',
  },
  {
    filename: 'build.gradle',
    exists: true,
    language: 'java',
    framework: 'android',
  },
  {
    filename: 'Gemfile',
    exists: true,
    grep: /rails/,
    language: 'ruby',
    framework: 'rails',
  },
  {
    filename: 'Gemfile',
    exists: true,
    language: 'ruby',
  },
  {
    filename: 'Dockerfile',
    exists: true,
    language: 'docker',
  },
  {
    filename: 'docker-compose.yml',
    exists: true,
    language: 'docker',
  },
  {
    filename: 'project.clj',
    exists: true,
    language: 'clojure',
  },
  {
    filename: 'mix.exs',
    exists: true,
    language: 'elixir',
  },
];

gumshoe.run(baseDir, rules, (err, res) => {
  if (err) {
    process.exit(1);
  }

  const lang = mappings[res.framework || res.language];

  if (lang) {
    console.log(lang);
  }
});

theme.zsh

project_type() {
  local lang=$(node ~/Code/src/internal/powerlevel9k-project-type-nerdfont/src/index.js)
  if [[ -z $lang ]]; then
    echo -n "\ufb26"
  else
    echo -n "\u$lang"
  fi
}

POWERLEVEL9K_CUSTOM_PROJECT_TYPE="project_type"
POWERLEVEL9K_CUSTOM_PROJECT_TYPE_FOREGROUND="black"
POWERLEVEL9K_CUSTOM_PROJECT_TYPE_BACKGROUND="yellow"