Dev Runner

Develop miniapps independently with the shared Nebula Dev Runner, without maintaining host configuration inside the miniapp project.

Nebula Dev Runner is the shared development host used for independent miniapp development.

For miniapp developers, there is only one main path:

npx nebula miniapp dev

The CLI prepares and opens Dev Runner, then switches it to the current miniapp. Developers usually do not need to care about Dev Runner installation or startup details.

What Dev Runner is

Dev Runner is also a Host.

Its role is not to replace a real product Host, but to provide Host developers with a reusable development environment. It lets miniapp developers build pages independently and rely on mocked Host APIs, such as user profile, permission state, or business context.

For business safety, we do not recommend putting real business logic, production data access, or sensitive host logic directly into the shared Dev Runner. Dev Runner is better for development-time mocks, default behavior, and debugging support. Real implementations should stay in the production Host, or be handled by a custom Runner in a controlled environment.

Its goals are:

keep miniapp projects clean, without ios/ or android/
let miniapp developers run and debug pages independently
make Dev Runner the development host that already integrates @nebula-rn/host-apis, providing basic Host APIs and default development behavior

Quick start

# 1. create a pure miniapp project
npx nebula create miniapp hello-nebula

cd hello-nebula

# 2. start development for the current miniapp
npx nebula miniapp dev

In the current implementation:

npx nebula miniapp dev exposes via Metro:
- /app.json
- index.bundle?...
The CLI automatically:
- starts the miniapp Metro
- prepares Dev Runner's Metro
- installs/opens Dev Runner for the target platform
- switches Dev Runner to the current miniapp

If you only want to start the miniapp Metro without launching Runner automatically, use:

npx nebula miniapp dev --no-runner

Built-in Dev Runner capabilities

Dev Runner already integrates @nebula-rn/host-apis, so common Host APIs can be used directly without extra configuration.

For example:

scanCode
previewImage
showToast
showModal

If your team has business API needs, such as:

getUserProfile
getTenantInfo
getFeatureFlags

See Custom APIs to extend your own Host APIs.

Custom Runner

If your team needs stronger customization than the default Dev Runner, such as:

branded UI
custom native modules
behavior closer to the real Host

You can use:

npx nebula create runner my-runner

This generates a customizable Dev Runner project.

Quick start

Built-in Dev Runner capabilities

Custom Runner

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