# Brownfield Navigation

> Route React Native calls to existing native screens through a generated Brownfield navigation contract.

- Skill: `callstack/brownfield-navigation` (Agent Skill, multi-file: 5 files)
- Install (CLI): `npx skillmds@latest add callstack/brownfield-navigation`
- Raw SKILL.md: https://api.skillmd.com/api/skills/callstack/brownfield-navigation/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- License: MIT
- Author: callstack (https://skillmd.com/u/callstack)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/callstack/brownfield-navigation

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# Overview

Brownfield navigation has three steps:
1. Define `brownfield.navigation.ts`
2. Run `npx brownfield navigation:codegen`
3. Wire native delegates before JS calls

Read only the smallest reference that matches the question.

## Routing (concern -> file)

Concern | Read
--------|------
Contract file location, supported signatures, codegen command, generated artifacts | [`references/setup-codegen.md`](references/setup-codegen.md)
Calling methods from React Native, `undefined is not a function`, API drift after contract edits | [`references/javascript-usage.md`](references/javascript-usage.md)
iOS-only delegate implementation and startup registration | [`references/native-ios-integration.md`](references/native-ios-integration.md)
Android-only delegate implementation and startup registration | [`references/native-android-integration.md`](references/native-android-integration.md)

## Minimal command reference

```bash
npx brownfield navigation:codegen
npx brownfield package:ios
npx brownfield package:android
npx brownfield publish:android
```