What is link-core used for?

It clones bullet_train-core and links gems for local development by adding local paths in the Gemfile while preserving the BULLET_TRAIN_VERSION.

Which gem lines get updated with a path?

Only lines that reference BULLET_TRAIN_VERSION are updated to include path: "local/bullet_train-core/ ".

Do I need to remove remote gem references?

No, you keep BULLET_TRAIN_VERSION and add the local path to enable local development without removing version constraints.

link-core

npx machina-cli add skill bullet-train-co/bullet_train-claude_code/link-core --openclaw

Files (1)

SKILL.md

1.6 KB

Link Bullet Train Core for Local Development

This skill checks out the bullet_train-core repository and links all contained Ruby gems in the Gemfile for local development.

Steps

Clone the repository (if not already present):
- Check if ./local/bullet_train-core exists
- If not, create ./local/ directory and clone via SSH:
```
git clone git@github.com:bullet-train-co/bullet_train-core.git ./local/bullet_train-core
```
Discover gems in the cloned repo:
- List all directories in ./local/bullet_train-core/ that contain a .gemspec file
- These are the gems that need to be linked
Update the Gemfile:
- For each bullet_train gem currently using BULLET_TRAIN_VERSION, add a , path: "local/bullet_train-core/<gem_folder>" option
- The gem folder name typically matches the gem name (with underscores)
- Transform lines like:
```
gem "bullet_train", BULLET_TRAIN_VERSION
```
  to:
```
gem "bullet_train", BULLET_TRAIN_VERSION, path: "local/bullet_train-core/bullet_train"
```
Run bundle install:
- After updating the Gemfile, run bundle install to link the local gems

Important Notes

The SSH URL for the repo is: git@github.com:bullet-train-co/bullet_train-core.git
Keep the BULLET_TRAIN_VERSION in place so version compatibility is maintained
Only modify gem lines that reference BULLET_TRAIN_VERSION
The local path should be relative: local/bullet_train-core/<gem_name>

Source

git clone https://github.com/bullet-train-co/bullet_train-claude_code/blob/main/skills/link-core/SKILL.mdView on GitHub

Overview

This skill clones the bullet_train-core repo into a local directory and links all discovered gems for development. It updates the host app's Gemfile to point to local paths while preserving BULLET_TRAIN_VERSION for compatibility, then runs bundle install.

How This Skill Works

The tool checks for ./local/bullet_train-core, clones the repo if missing, then scans for gem folders containing a .gemspec. It updates Gemfile lines that use BULLET_TRAIN_VERSION to include a path option pointing to local/bullet_train-core/<gem_folder>, and finally runs bundle install to link the local gems while keeping the version constraint intact.

When to Use It

Setting up a new development environment to work on local Bullet Train core gems
Testing changes in bullet_train-core within a host Rails app without publishing new gem versions
Ensuring Gemfile uses local paths rather than remote gems when BULLET_TRAIN_VERSION is present
Onboarding teammates to the local gem linking workflow for Bullet Train core
Troubleshooting bundler or dependency resolution after cloning bullet_train-core

Quick Start

Step 1: Clone the repository into local/bullet_train-core if ./local/bullet_train-core does not exist
Step 2: Discover gem folders by locating directories containing a .gemspec in ./local/bullet_train-core
Step 3: For each gem line using BULLET_TRAIN_VERSION in your Gemfile, add path: "local/bullet_train-core/<gem_folder>" and run bundle install

Best Practices

Only modify gem lines that reference BULLET_TRAIN_VERSION
Keep BULLET_TRAIN_VERSION in place to maintain compatibility
Ensure the local path matches the gem folder name (local/bullet_train-core/<gem_name>)
Use path: "local/bullet_train-core/<gem_folder>" syntax in Gemfile
Run bundle install after updating the Gemfile to apply the local links

Example Use Cases

A Rails app uses bullet_train-core 2.1.0; you clone the core locally and link bullet_train as local/bullet_train-core/bullet_train in the Gemfile, then run bundle install
Developers add bullet_train_extensions to the Gemfile with a path to local/bullet_train-core/bullet_train_extensions and verify changes via bundle exec rails console
After forking bullet_train-core, a teammate links the forked gems locally using the BULLET_TRAIN_VERSION constraint and tests integration in the host app
You identify multiple gems in bullet_train-core with .gemspec files and confirm their paths are correctly reflected in the Gemfile
An onboarding session demonstrates updating Gemfile lines with paths for all gems matching Bullet Train versions and validating with bundle install

Frequently Asked Questions

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