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Interview with driving forces behind web dev projects jsDelivr & jSter

If you are a web developer, you should definitely check out jsDelivr and JSter.

JSter is a catalog of over 1,100 JavaScript libraries and tools for web development, where users can rate contributions, and share their experience with others. jsDelivr is a free CDN (Content Delivery Network) where any web developer can host their files, including CSS, fonts, JavaScript, jQuery plugins, etc. Currently almost 600 projects are hosted on jsDelivr.

To find out more about these two projects, we interviewed Dmitriy Akulov (representing jsDelivr) and Juho Vepsäläinen (representing JSter).

Q: Let’s start with jsDelivr, Dmitriy. According to the site, jsDelivr is “a free super-fast CDN for developers and webmasters.” Explain a bit more what that means.

A: jsDelivr is a public open-source CDN where anyone can submit a project to be hosted and delivered by our network. Most people probably know that Google hosts jQuery and a few other popular libraries. We don’t look at the popularity of the project to approve it for inclusion in jsDelivr. Plus a lot more types of projects are allowed, like CSS frameworks, fonts, WordPress plugins etc. By using GitHub, we allow the community to fully interact with jsDelivr by adding and updating files.

When we say super-fast we really mean it. Performance is key to everything we do.

What makes it super-fast is the unique multi-CDN infrastructure we use. MaxCDN (NetDNA) and (which is powered by the huge federated network of OnApp) agreed to combine their powers for the good of the open source community and to sponsor us and become our CDN providers.

All traffic to our CDN providers is load balanced based on availability and performance for each individual user by another official sponsor of ours, the company Cedexis. This unique system not only gives us the best possible uptime and performance but also allows us to expand dynamically and add new providers on the fly.

Q: There are many CDNs available to developers, webmasters, and others today. Why should they use jsDelivr?

A: Currently we host 570 projects, which makes us the biggest public CDN out there.

Plus jsDelivr is free, fast and open source. We have no strict rules, and we don’t take weeks to respond to requests and update projects. Everything happens within a couple of days, and any GitHub pulls are merged even faster.

Since the project is non-profit everything is done with the users in mind. We do not rely on a single CDN provider, which makes jsDelivr independent, and no single company can influence us with their decisions. As we mentioned, our setup is very flexible, and we have good relationships with plenty of CDN providers. So even if it would happen that we experience issues with one provider we can switch without any problems.

Q: Then let’s move on to JSter, Juho. What is it about? What motivated its development?

A: You could say the whole thing got started in January 2011. A friend of mine asked for a list of JavaScript game engines. As I could not find one I created one, and for one reason or another I shared it at the JavaScript section of Reddit. Encouraged by the feedback I decided to start cataloguing JavaScript libraries and tools. This led to the birth of jswiki.

In all its simplicity, it has proven to be a valuable community resource. Early 2012 I was approached by the developer of, Guillermo Rauch. He proposed that it would be a nice idea to take the content and wrap it into an alternative user interface. Some further development and ghw was born. It is a tool that allows me to achieve just this, and you can see the results at

Even though this was a step forward, there was still some functionality missing. Some of it simply cannot be implemented without having some kind of a backend. The developer of Symfohub, Michael Bodnarchuk, contacted me some time after this. Given that he had some technology already and I had content and some vision on where to take it we decided to collaborate.

As a result, was born. The jswiki data provided us a starting point, and it has grown immensely since. Besides having just a catalog, we have also produced original content for our blog. And we are continuously improving the service. Our primary goal is to make it easier for people to find new libraries and make their own libraries more visible. It is so very easy to miss some awesome library you just might need.

Q: If someone would want to help out with either project, how could they do that?

A: For JSter we are continuously looking for ways to improve our site and want to make it more useful for you, the developers. You can highlight immediate issues via that little “Problems?” button in the corner of the site. Alternatively you can poke us directly through email for more complex queries.

Of course, given that we are basically a library catalog we may be missing some great projects so we definitely don’t mind if you help us find those. So go ahead and add anything you might feel we’re missing.

In terms of jsDelivr, the best help for us is the support of the community. Add a new project, update an old one, submit some feature requests, etc. This helps a lot. And of course use our CDN and integrate it in your services. The increasing number of hits, to see how people use it, that’s what keeps us going.

Q: Finally, can you tell us something about the future for either site?

A: For JSter, we have some interesting things in store. This includes programmatic access to the data, code metrics, and, of course, more blog posts. Basically we want to improve our offering and make it more appealing to the community.

When it comes to jsDelivr, we plan an even bigger and faster network by combining region-specific providers. In addition, we always try to develop new features that will help and benefit our users.

If anyone reading this has some ideas, just send them to us, we’re always willing to listen to ideas.

Have you created a cool web dev project?

We’d like to say a big thank you to Dmitriy and Juho. Neither project may be that big yet but the passion that drives these guys to keep developing and improving the projects is impressive. We can only think that there are big things in store for JSter and jsDelivr in the future.

Have you created something cool, some project for the community, which you’d like to share with us? We’d love to hear all about it so please let us know in the comments below or reach out to us on Twitter.

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