Yith: Private npm registry | Craftship

Yith: Private npm registry

Handle private npm packages in the enterprise. No servers required!

The Craftship team have been working on a new Open Source project to help organizations that require keep intellectual property but still wish to share modules across teams and use npm modules from the offical registry.

Having worked in many large organizations they use GitHub Enterprise which helps give them the ability to have a standard joiners and leavers policy across thousands of employees of which all third party systems need to have single sign on (normally via LDAP) so that they can ensure access control is managed in one place.

One thing to note is that GitHub have recently announced at their GitHub Universe conference they are rolling out SSO for SAML based authentication amongst a whole heap of exciting new features. We are hoping this means that in the enterprise organizations will look to use hosted GitHub rather than having the overhead of managing it internally.

Serverless astract imge

What is yith?

Yith is a private npm registry that uses the Serverless framework to reduce cost and overhead of any instances required in your cloud provider (currently AWS) to host a private npm registry.

Every operation that is required for the registry is a Lambda function, a bite size function that runs only on demand when required. The up shot of doing this is that in the case of Amazon you are only charged for the time in which the function runs. This makes hosting a private npm registry using yith incredibly cost effective.

Each function when an npm command is executed makes a request to and endpoint via Amazon AWS API Gateway which then invokes the function to run and produce the relevant response required for the npm CLI.

We basically used Charles to sniff the https requests being made by the npm CLI and replicated the endpoints (which are ultimately is CouchDB) :D

yith cloud diagram

How does my team use it ?

Once deployed using the serverless framework each team member just sets the relevant npm registry url (npm set registry) to the deployment url specified. It is built to be compatiable with the npm CLI you all know and love!


For authentication yith overrides using npm login to authenticate and instead uses github.com or your github enterprise instance to authenticate and allow publishing of packages. All you need is to setup a GitHub developer application and update the relevant config file with the client id and secret.

To support two factor auth we had to bei a bit cheeky and require your username to end with a full stop then the one time authentication password, for example username.123456.

Publishing packages

Once logged in via GitHub publishing packages is the same as you have done before using npm publish, simple!

Installing packages

To install a package when you use npm install yith will first check the S3 bucket to see if it exsists in your private registry. If it does not exist it will then go off to the real npm registry and download it from there.


Hopefully this gives you a nice introduction to what yith is and a high level overview of how it works. We have plenty of features we want to add in the upcoming months and hope to get some contributions from the wider community.

One thing to note is that we have found Serverless RC1 (expected as it is very new!) to have a few minor issues. You will notice until we get some of our pull requests merged into Serverless we are running the yith on our own fork / branch for now.

Yith GitHub repository

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