slowlane

A simple CLI for managing App Store and Google Play metadata.

Fastlane is powerful but complex to set up. Slowlane focuses on one thing: making it easy to update localized metadata (titles, descriptions, keywords) across multiple languages. Screenshots, builds, and submitting for review are left to the respective console UIs.

Note: this code is vibe coded with Claude Code, but it's not a "one prompt" project; I was very specific in what I want to get, and I'm actually using this tool for managing metadata for my apps, and it saves a lot of time for me, because App Store Connect and Play Console are so bad when it comes to managing several localizations at once, and because I never figured out how to use Fastlane (maybe it's just not for me).

Typical Workflow

1. Export current metadata from the live version as a starting point
2. Edit the JSON file to update descriptions, keywords, etc. Use ChatGPT as needed to add translations to new locales. The list of locales supported by Apple and Google can be retrieved by slowlane apple list-locales and slowlane google list-locales.
3. Create a new version (Apple only - Google doesn't require this for metadata)
4. Import the updated metadata from the JSON file
5. Review and submit in the respective console UI

This procedure does not cover writing release notes for Google Play releases; I don't normally need a tool for that because ChatGPT can generate the pseudo-XML they require. I might add it to the subsequent versions though (maybe with an OpenAI API token in the config, to handle translation).

Setup

Apple App Store Connect

1. Go to App Store Connect > Users and Access > Integrations > App Store Connect API
2. Generate a new API key with "App Manager" role
3. Download the .p8 private key file
4. Note the Key ID and Issuer ID

Google Play Console

1. Go to Google Cloud Console
2. Create a project (or use existing)
3. Enable both APIs:
   • Google Play Developer Reporting API (for listing apps)
   • Google Play Android Developer API (for metadata operations)
4. Create a Service Account with a JSON key
5. In Google Play Console, go to Users and Permissions, invite your service account email, and grant "Manage store presence" and "Releases" permissions

Configuration

Create slowlane.toml in your project directory:

[appstore_connect]
issuer_id = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
key_id = "XXXXXXXXXX"
private_key_path = "./AuthKey_XXXXXXXXXX.p8"

[google_play]
service_account_path = "./your-service-account.json"

Add sensitive files to .gitignore:

slowlane.toml
*.p8
*-service-account.json

Usage

Apple App Store Connect

# List all apps
npx slowlane apple list-apps

# List supported locales
npx slowlane apple list-locales
npx slowlane apple list-locales --json

# View metadata for all languages (from editable version)
npx slowlane apple get-metadata com.example.app

# View full metadata for a specific language
npx slowlane apple get-metadata com.example.app en-US

# Save metadata from live version to JSON
npx slowlane apple get-metadata com.example.app --from live --json > metadata.json

# Create a new version
npx slowlane apple create-version com.example.app 2.0.0

# Update metadata from JSON file
npx slowlane apple set-metadata com.example.app -f metadata.json

Google Play

# List all apps
npx slowlane google list-apps

# List supported locales
npx slowlane google list-locales
npx slowlane google list-locales --json

# View metadata for all languages
npx slowlane google get-metadata com.example.app

# View full metadata for a specific language
npx slowlane google get-metadata com.example.app en-US

# Save metadata to JSON
npx slowlane google get-metadata com.example.app --json > metadata.json

# Update metadata from JSON (changes are sent for review automatically)
npx slowlane google set-metadata com.example.app -f metadata.json

Author

Alexander Fenster, [email protected]

100% vibe coded with Claude Code