Understanding walkerOS Development

Overview

walkerOS follows extreme programming principles with strict conventions. This skill is your foundation before writing any code.

Core principle: DRY, KISS, YAGNI. Test first. Verify before claiming complete.

Commands

Command	Purpose
`npm install`	Install all dependencies
`npm run dev`	Watch mode for all packages
`npm run build`	Build all packages
`npm run test`	Run all tests
`npm run lint`	ESLint + TypeScript check
`npm run format`	Prettier formatting

Validation before commit: npm run build && npm run test && npm run lint

XP Principles (Non-Negotiable)

Principle	In Practice
DRY	Use `@walkeros/core` utilities, don't reimplement
KISS	Minimal code to solve the problem
YAGNI	Only implement what's requested
TDD	Test first, watch it fail, then implement
No `any`	Never use `any` in production code (tests are exception)

Folder Structure

code

packages/
├── core/           # Platform-agnostic types, utilities, schemas
├── collector/      # Central event processing engine
├── config/         # Shared config (eslint, jest, tsconfig, tsup)
├── web/
│   ├── core/       # Web-specific utilities
│   ├── sources/    # browser, dataLayer
│   └── destinations/ # gtag, meta, api, piwikpro, plausible
└── server/
    ├── core/       # Server-specific utilities
    ├── sources/    # gcp
    └── destinations/ # aws, gcp, meta

apps/
├── walkerjs/       # Ready-to-use browser bundle
├── quickstart/     # Code examples (source of truth for patterns)
└── demos/          # Demo applications

Core Package Usage

Always import from @walkeros/core:

typescript

// Types
import type { WalkerOS } from '@walkeros/core';

// Utilities
import {
  getEvent,
  createEvent, // Event creation
  getMappingEvent,
  getMappingValue, // Transformations
  isString,
  isObject,
  isDefined, // Type checking
  assign,
  clone, // Object operations
  tryCatch,
  tryCatchAsync, // Error handling
} from '@walkeros/core';

Config package for shared tooling:

•ESLint config: @walkeros/config/eslint
•Jest config: @walkeros/config/jest
•TSConfig: @walkeros/config/tsconfig
•Tsup config: @walkeros/config/tsup

Testing

REQUIRED SKILL: Use testing-strategy for detailed testing patterns.

Quick reference:

•Use env pattern for mocking (not Jest mocks)
•Import from dev.ts for examples
•Test first, watch it fail
•Verify before claiming complete

•testing-strategy skill
•packages/core/ - Core utilities
•packages/config/ - Shared configuration
•apps/quickstart/ - Validated examples

understanding-development