Skip to content
git clone --recursive on steroids
Ruby Shell
Branch: master
Clone or download
justinseanmartin Merge pull request #39 from square/jmartin/unable-to-read-sha1-error
Clear the cache on an 'unable to read sha1' error
Latest commit 47fbd43 Nov 9, 2019
Type Name Latest commit message Commit time
Failed to load latest commit information.
bin Update RuboCop Jan 17, 2019
lib Clear the cache on an 'unable to read sha1' error Nov 8, 2019
script Initial revision: 1.0.0 Nov 13, 2015
spec Clear the cache on an 'unable to read sha1' error Nov 8, 2019
.gitignore Add :lock files to .gitignore Jan 17, 2019
.rubocop.yml Retry when deltas are missing Aug 15, 2019
.rubocop_todo.yml Handle mirror corruption with retries Jun 27, 2019
.travis.yml Only test on non-EOL rubies Jun 27, 2019 Add file Dec 11, 2015
Gemfile.lock Clear the cache on an 'unable to read sha1' error Nov 8, 2019
Rakefile Ruby 2.1, 2.2 compatibility Jan 17, 2019
git-fastclone.gemspec Update to use Terrapin instead of Cocaine Jan 17, 2019
kochiku.yml Initial revision: 1.0.0 Nov 13, 2015


Twitter: @longboardcat13 License Build Status Gem Version

git-fastclone is git clone --recursive on steroids.

Why fastclone?

Doing lots of repeated checkouts on a specific machine?

Repository 1st Fastclone 2nd Fastclone git clone cp -R
angular.js 8s 3s 6s 0.5s
bootstrap 26s 3s 11s 0.2s
gradle 25s 9s 19s 6.2s
linux 4m 53s 1m 6s 3m 51s 29s
react.js 18s 3s 8s 0.5s
tensorflow 19s 4s 8s 1.5s

Above times captured using time without verbose mode.

What does it do?

It creates a reference repo with git clone --mirror in /var/tmp/git-fastclone/reference for each repository and git submodule linked in the main repo. You can control where it puts these by changing the REFERENCE_REPO_DIR environment variable.

It aggressively updates these mirrors from origin and then clones from the mirrors into the directory of your choosing. It always works recursively and multithreaded to get your checkout up as fast as possible.

Detailed explanation here.


gem install git-fastclone
git fastclone [options] <git-repo-url>

-b, --branch <branch>   Clone a specific branch
-v, --verbose           Shows more info
-c, --color             Pretty colors!

Change the default REFERENCE_REPO_DIR environment variable if necessary.

Cygwin users need to add ~/bin to PATH.

How to test?

Manual testing:

ruby -Ilib bin/git-fastclone <git url>

Compatible with Travis and Kochiku.


If you would like to contribute to git-fastclone, you can fork the repository and send us pull requests.

When submitting code, please make every effort to follow existing conventions and style in order to keep the code as readable as possible.

Before accepting any pull requests, we need you to sign an Individual Contributor Agreement (Google form).


thoughtbot/terrapin - jyurek and collaborators






Copyright 2015 Square Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
See the License for the specific language governing permissions and
limitations under the License.
You can’t perform that action at this time.