Installation

Yarn

yarn add mobx-keystone

npm

npm install --save mobx-keystone

This library requires a more or less modern JavaScript environment to work, namely one with support for:

• MobX 6, 5, or 4 (with its gotchas)
• Proxies
• Symbols
• WeakMap/WeakSet

In other words, it should work on mostly anything except it won't work in Internet Explorer.

If you are using TypeScript, then version 4.2.0+ is recommended, though it might work with older versions.

Transpiler configuration

This library uses JavaScript decorators and class properties which are supported via the following transpiler configurations:

TypeScript Compiler

tsconfig.json

{
  // ...
  "compilerOptions": {
    // ...
    "experimentalDecorators": true,
    // MobX 5/6
    "useDefineForClassFields": true
    // MobX 4
    "useDefineForClassFields": false
  }
}

Babel

babel.config.json

{
  "presets": [
    // ...
    // If you use TypeScript
    ["@babel/preset-typescript", { "allowDeclareFields": true }]
  ],
  "plugins": [
    ["@babel/plugin-proposal-decorators", { "version": "legacy" }],
    // MobX 5/6
    ["@babel/plugin-proposal-class-properties"]
    // MobX 4
    ["@babel/plugin-proposal-class-properties", { "loose": true }]
  ]
}

SWC

.swcrc

{
  "jsc": {
    "parser": {
      "syntax": "typescript", // "ecmascript" if you use JavaScript
      "decorators": true
    },
    "transform": {
      // Optional if you use TypeScript
      // Required if you use JavaScript
      "legacyDecorator": true
    },
    // MobX 5/6
    "loose": false
    // MobX 4
    "loose": true
  }
}