Ndjin services are separate web services, based on the Ndjin platform. They can be used either in an Ndjin application or on any other web project, regardless of the underlying technology.




Technical Questions

How is this different from Google Engine?

We are a layer higher than Google Engine as we provide all the stacks to operate on your model using web services. You could compare Google Engine as a database service with code engine on top of it. We provide more than this, since you can build your object model with full relations association between objects, executable methods and state transitions. In fact, we could run part of our service on top of Google Engine.
By the way, Ndjin could run on any hardware platform that supports Java. You can run your ndjin instance on a dedicated server if you want to get full dedicated CPU power and private confinement.


Are you planning other scripting languages?


Scala support is on its way. We might soon support Java. Ruby and Python are partially supported (with no strong commitment right now). We have no plan for any other new scripting language right now.


What kind of software are you using?

Our current platform is powered by Linux running many Java applications and scripts. Right now we are using Jetty as web-server but we are planning to move to Apache Mina HTTP implementation for our specific needs. The data is stored in transactional distributed persistent graphs.


What is your underlying data model?

Our internal data model is a graph allowing each node to have many children and parents. Each application run its own graph and can refer to a node from another application or subset graph allowing distribution of data, and bridges between applications. Graphs are
stored in a transactional 'biggraph' designed to support billions of nodes (depending on underlying storage).


What kind of hardware are you using?

We don't have any strong hardware specification requirement : anything that could run Java should be fine. We've choosen to run on Amazon EC2 virtual platform, and have developed deployment and monitoring software on top of it, but technically we could operate on any hardware running Linux (with some performances or limitations depending on the available features).


How can your platform scale?

The underlying data storage system could theoretically scale infinitely. The front-end part is not currently clustered due to some limitations with statefull session data and cache propagation. We are working on enabling clustering features to our platform, but we also want to keep its architecture as simple as possible, and rely more on infrastructure virtualization for scaling. Rather that having millions of applications running on one platform instance, we would focus on having thousands of instances running thousands of applications.


You do not support UML spec or standard of OMG, will you one day?

Maybe but this is not our primary goal. We are focused on providing very simple platform and not an exhaustive features factory.


You guys have never heard of SOAP and WSDL standards?

Yes we have. And yes our webservice protocol is not based on SOAP and we don't provide WSDL so far.
Right now, we prefer to stick on something simple and efficient, based on HTTP/JSON or basic XML. But if there are strong requests from the community, we'll try to support these.


Is this a kind of dynamic EJB online?

You could say that :)). By dynamic we mean the capability to introspect and change your model at runtime.


Can I use my own domain name instead of a subdomain of ndjin.net for API call?

Yes you can ;). Right now you'll have to contact us, but we'll soon provide you an online form to manage your domain names parking.


Business Questions


Will your OpenSource and Free Service policy always remain?


We are developers ! We want to develop open softwares and launch a cool community around model driven platform as a service. We really don't think having a closed approach is good practice, so you can believe us, we'll try to go as far as we can in opensource software and free service. By the way, we are pretty well engaged in opensource community by leading few projects such as: OpenIM, POMStrap, NVDCMS, XMLPersistence.


Are my data safe?

Confidentiality and security are one of our top priority. We perform regular snapshot and complete remote mirror of the data stored in safe disks. We guarantee you that we will never access any of your data for our own purpose without your agreement.