Angular Microfrontends Micro Frontends Shell Container Contract

---
id: angular.microfrontends.micro-frontends-shell-container-contract
name: Micro-frontends Shell Container Contract
description: Define a thin Angular shell contract that handles routing, composition, fallback UX, and cross-cutting concerns without owning domain logic.
stack:
  - Angular
  - TypeScript
  - Nx
  - Module Federation
category: architecture
status: stable
version: 0.10.0
owner: NgAutoPilot
triggers:
  - shell container
  - host app
  - remote loading
  - container app
  - micro frontends shell
  - shell app contract
  - host shell
  - shell routing
  - shell composition
  - container boundary
  - shell fallback
compatibility:
  angular:
    min: "2"
    signalInputsFrom: "17"
    recommendedModern: "17+"
---

# Micro-frontends Shell Container Contract

Use this skill when a shell or host app composes multiple remotes.

## Core Rule

```txt
The shell orchestrates. Remotes own domain behavior.
```

## Shell Responsibilities

- routing
- composition
- layout chrome
- auth integration
- loading and error boundaries
- navigation contracts

## Purpose

Keep the shell thin and predictable while remotes own domain behavior.

## When to Use

Use this skill when a shell or container app composes multiple remotes.

## Do

- keep shell logic orchestration-only
- define fallback and retry behavior
- keep route ownership and cross-cutting concerns explicit

## Review Checklist

- [ ] The shell owns only composition and cross-cutting concerns.
- [ ] Route ownership is explicit.
- [ ] Remote failure has a fallback path.
- [ ] Shared dependencies are minimal.

## Do Not

- put business logic in the shell
- couple shell internals to remote implementation details
- let the shell become a hidden monolith

## Expected Output

Return:

1. Shell responsibilities.
2. Route ownership.
3. Fallback and retry behavior.
4. The smallest safe shell contract.